Validation of dietary assessment methods in the UK arm of EPIC using weighed records, and 24-hour urinary nitrogen and potassium and serum vitamin C and carotenoids as biomarkers

Assessing the gut microbiota composition in older adults: connections to physical activity and healthy ageing

The composition and functionality of the gut microbiota (GM) changes throughout the life course. As we move into older age, it starts to shift towards a less healthy one, which may lead to an imbalance in the GM community. Strategies that can reverse age-related dysbiosis are an important part of healthy aging. Little is known about the GM composition of older adults with different physical activity (PA) levels and whether it might contribute to healthy ageing. The aim of this study was to compare the GM composition of older adults with different PA levels and assess if it is associated with healthy ageing. 101 participants aged between 65-85 years undertook anthropometric measures, a 6-min walking test, wore an accelerometer for 7 days and provided a faecal sample. Faecal GM composition was analysed using 16S rRNA sequencing. We found that those who fulfilled the WHO/UK PA recommendations had higher relative abundance of several health-related bacteria such as Lactobacillus, F. prausnitzii and Roseburia intestinalis and lower abundance of disease-associated bacteria such as D.piger or Enterobacterales when compared to those who did not reach PA recommendations. These findings suggest that PA might improve the GM composition and has the potential to, at least partially, revert age-associated dysbiosis and promote healthy ageing.

Association of Diet and Waist-to-Hip Ratio With Brain Connectivity and Memory in Aging

Importance

Epidemiological studies suggest that lifestyle factors are associated with risk of dementia. However, few studies have examined the association of diet and waist to hip ratio (WHR) with hippocampus connectivity and cognitive health.

Objective

To ascertain how longitudinal changes in diet quality and WHR during midlife are associated with hippocampal connectivity and cognitive function in later life.

Design, Setting, and Participants

This cohort study analyzed data from participants in the Whitehall II Study at University College London (study inception: 1985) and Whitehall II Imaging Substudy at the University of Oxford (data collection: 2012-2016). Healthy participants from the Whitehall II Imaging Study with a mean age of 48 years at baseline to 70 years at magnetic resonance imaging (MRI) were included if they had information on diet from at least 1 wave, information on WHR from at least 2 waves, and good-quality MRI scans. Study analyses were completed from October 2019 to November 2024.

Exposures

Diet quality was measured in participants(mean age, 48 years at baseline to 60 years) using the Alternative Healthy Eating Index-2010 score, which was assessed 3 times across 11 years. WHR was measured 5 times over 21 years in participants aged 48 to 68 years.

Main Outcomes and Measures

White matter structural connectivity assessed using diffusion tensor imaging, hippocampal functional connectivity assessed using resting-state functional MRI, and cognitive performance measures. Brain imaging and cognitive tests were performed at a mean (SD) age of 70 (5) years.

Results

The final diet quality sample comprised 512 participants (403 males [78.7%]; mean [SD] age, 47.8 [5.2] years), and the final WHR sample included 664 participants (532 males [80.1%]; mean [SD] age, 47.7 [5.1] years). Better diet quality in midlife and from midlife to late life was associated with higher hippocampal functional connectivity to the occipital lobe and cerebellum (left hippocampus: 9176 mm3, P < .05; left hippocampus and to the right cerebellum: 136 mm3, P = .04) and better white matter integrity as measured by higher fractional anisotropy (FA; 19 432 mm3, P < .05) and lower diffusivity (mean diffusivity [MD]: 5560 mm3, P < .05; axial diffusivity [AD]: 2600 mm3, P < .045; AD in fornix: β [SE] = 0.26 [0.11], false discovery rate-corrected P = .02). Higher WHR in midlife was associated with higher MD and radial diffusivity (covering 26.4% [333 088 mm3, P < .001] and 23.1% [291 888 mm3, P < .05], respectively, of the total white matter tracts in the cingulum and superior and inferior longitudinal fasciculus) and lower FA in the corticospinal tract (covering 4.9% of the white matter skeleton), including the inferior longitudinal fasciculus and cingulum (61 272 mm3, P < .05). Associations between midlife WHR, working memory, and executive function were partially mediated by diffusivity (eg, digit span was mediated by global FA: β = -2.96-03; 95% CI, -5.56-03 to -1.01-03; P < .001).

Conclusions and Relevance

This cohort study found that healthier diets and lower WHR throughout midlife were associated with better brain and cognitive health in older age. The findings suggest that interventions to improve diet and manage central obesity might be most effective between ages 48 and 70 years.

The development of a food-group, tree classification method and its use in exploring dietary associations with metabolic dysfunction-associated Steatotic liver disease (MASLD) and other health-related outcomes in a UK population

Background

Metabolic dysfunction-Associated Steatotic Liver Disease (MASLD) affects up to one in five people in the UK, with persistent overeating and a sedentary lifestyle being significant risk factors. Exploring dietary patterns at a food level is a novel approach to understand associations between diet and disease.

Methods

This cross-sectional case-control study included 168 MASLD patients and 34 healthy controls from Nottingham (UK). Dietary data were collected using the EPIC-food frequency questionnaire. A food-group, tree classification method was developed which categorized 923 ingredients into three levels (main food group, sub-types, and cooking methods) and intakes were associated with clinical outcomes using logistic regression and degree of liver fibrosis using linear regression.

Results

Significant associations were found for red meat intake with MASLD (OR [CI]: 1.013 [1.001-1.025]) and fibrosis (Beta [SE]: +0.048 [0.013]); intakes of nuts (OR [CI]: 0.951 [0.905-0.999]); and fish (OR [CI]: 0.985 [0.971-0.999]) with MASLD; "Cereals and cereals products", "salt and gravy" and baked foods with fibrosis (Beta [SE]: +0.018 to +0.057 [0.005-0.23]); white and organ meat (Beta [SE]: -0.04 to -0.61 [0.015-0.249]); diet soda (OR [CI]: +0.01 [1-1.003]) and red meat intakes (OR [CI]:+0.002 [1.002-1.016]) with T2DM; wholegrain wheat, red meat, and semi-skimmed dairy intakes with hypercholesterolemia (ORs [CI]: -0.003 to -0.023 [1-1.043]); "herbs and spices" and wholegrain rice with hypercholesterolaemia (ORs [CI]: -0.08 to -0.98 [0.159-0.989); fresh herbs and boiled foods intakes with hypertension (ORs [CI]: -0.001 to -2.21 [0.013-1]).

Conclusion

The study introduces a new food-group, tree classification method to characterise UK diet data and identify risk factors for MASLD, potentially informing the development of culturally applicable dietary guidelines designed to improve public health.

Adherence to unhealthy diets is associated with altered frontal gamma-aminobutyric acid and glutamate concentrations and grey matter volume: preliminary findings

OBJECTIVES

Common mental disorders (CMD) are associated with impaired frontal excitatory/inhibitory (E/I) balance and reduced grey matter volume (GMV). Larger GMV (in the areas that are implicated in CMD-pathology) and improved CMD-symptomatology have been observed in individuals who adhere to high quality diets. Moreover, preclinical studies have shown altered neurometabolites (primarily gamma-aminobutyric acid: GABA and glutamate: GLU) in relation to diet quality. However, neurochemical correlates of diet quality and how these neurobiological changes are associated with CMD and with its transdiagnostic factor, rumination, is unknown in humans. Therefore, in this study, we examined the associations between diet quality and frontal cortex neuro-chemistry and structure, as well as CMD and rumination in humans.

METHODS

Thirty adults were classified into high and low diet quality groups and underwent 1H-MRS to measure medial prefrontal cortex (mPFC) metabolite concentrations and volumetric imaging to measure GMV.

RESULTS

Low (vs High) diet quality group had reduced mPFC-GABA and elevated mPFC-GLU concentrations, as well as reduced right precentral gyrus (rPCG) GMV. However, CMD and rumination were not associated with diet quality. Notably, we observed a significant negative correlation between rumination and rPCG-GMV and a marginally significant association between rumination and mPFC-GLU concentrations. There was also a marginally significant association between mPFC-GLU concentrations and rPCG-GMV.

DISCUSSION

Adhering to unhealthy dietary patterns may be associated with compromised E/I balance, and this could affect GMV, and subsequently, rumination.

Comparison of Dietary Patterns and Daily Food Intake Across Kidney Disease Stages in England: An A-Posteriori Cluster Analysis

OBJECTIVE

Dietary patterns are rapidly becoming a major focus of medical nutrition therapy in chronic kidney disease (CKD) and the analysis of dietary patterns has emerged as a practical approach to evaluate qualitative as well as quantitative aspects of overall diet. In an a-posteriori data-driven approach, dietary patterns are based on the actual food intake of the population evaluated. Investigation of dietary patterns in CKD is not well-described, and to our knowledge, has not been conducted in a UK-based cohort.

METHODS

Adult participants with a diagnosed kidney condition (CKD 1-5 not requiring dialysis) were recruited into a multicenter observational cross-sectional study. Dietary intake was assessed using the European Prospective Investigation of Cancer in Norfolk Food Frequency Questionnaire. Logistic Principal Component Analysis was used to identify food group clusters. Differences between groups were assessed using univariate general linear modeling.

RESULTS

In total, 696 patients were included. The mean age was 64.7 (±14.0) years, 61% of the cohort were male. Most participants were White British (89%). The mean estimated glomerular filtration rate was 36.6 (±20.9) mL/minute/1.732. We found differences in food group intake across stages (e.g., greater intake of nuts and seeds intake in CKD 1-2 versus CKD 4) and across sex (e.g., females had a higher intake of fruit and vegetables versus males). Comparison with the reference cohort revealed that, overall, the CKD cohort had reduced intakes of food stuffs such as cereals and cereal products, but higher intakes of groups such as meat and meat products. There were limited differences in micronutrients, although vitamin B2 and calcium were higher in earlier stages.

CONCLUSION

Overall, the findings from a novel a-posteriori approach underline the complex diversity of food patterns in CKD. The findings from our study may inform dieticians and other health-care providers about the need to consider treatment modalities and stages when giving dietary recommendations.

Prospective Association of the Mediterranean Diet with the Onset of Cardiometabolic Multimorbidity in a UK-Based Cohort: The EPIC-Norfolk Study

BACKGROUND

Cardiometabolic multimorbidity (CMM), defined as the co-occurrence of 2 or more cardiometabolic diseases, including myocardial infarction (MI), stroke, and type 2 diabetes (T2D), is an increasing public health challenge. Although poor diet is a known risk factor for a first cardiometabolic disease (FCMD), the relationship with subsequent occurrence of CMM is less studied.

OBJECTIVES

This study aims to investigate the prospective association between baseline adherence to the Mediterranean diet and the onset of CMM across various follow-up durations.

METHODS

We used data from the European Prospective Investigation into Cancer-Norfolk cohort study of 21,900 adults, aged 40-79 free of prevalent MI, stroke, and T2D at baseline (1993-1997). A median-based Mediterranean diet score and a pyramid-based MDS (pyr-MDS) were used to measure baseline adherence to the Mediterranean diet. Multistate modeling was employed to investigate associations with the FCMD and the subsequent CMM event.

RESULTS

Over the entire follow-up period of 21.4 y (median), we observed 5028 FCMD and 734 CMM events. Multistate analysis indicated that the association between baseline Mediterranean diet and the risk of CMM may be stronger in shorter follow-up durations. Particularly, baseline pyr-MDS was significantly associated with the risk of subsequent CMM transitioning from FCMD when follow-up durations were limited to 10 and 15 y, with hazard ratio (95% confidence interval) being 0.67 (0.53, 0.84) and 0.80 (0.70, 0.92) per SD increase in pyr-MDS, respectively. Additionally, we observed that the risk of CMM transitioning from FCMD was modified by social class across shorter to longer follow-ups, where the impact of baseline Mediterranean diet was only significant in nonmanual workers.

CONCLUSIONS

Baseline adherence to the Mediterranean diet was potentially associated with a lower risk of CMM transitioning from FCMD, particularly during shorter follow-up periods.

Greater resting state functional connectivity of the medial prefrontal cortex with the thalamus, caudate, and putamen in individuals who adhere to the Mediterranean style diets

PURPOSE

Healthy diets are believed to be associated with a reduced risk of experiencing common mental disorders (CMDs) and related symptomatology (such as ruminative thinking), and with healthier brain chemistry and structure, especially in the frontal regions implicated in CMDs, cognitive control, and food choice. Nevertheless, there is very limited research on the relationship between diet health/quality and brain function. In this study we assessed the associations between adherence to the Mediterranean diet and resting state functional connectivity (rs-FC) of the prefrontal cortex (PFC) with the whole brain and whether this connectivity would be associated with ruminative thinking as a transdiagnostic factor for CMDs.

METHODS

Thirty-seven adults (Mean Age = 25.57, SD = 7.18) completed the Mediterranean Diet Adherence Screener (MEDAS) and were classified into high- and low-quality diet groups and completed the Ruminative Response Scale. All participants underwent resting-state functional MRI (fMRI) to determine whole-brain rs-FC of the medial prefrontal cortex (mPFC).

RESULTS

Participants in the high MEDAS group (vs. low MEDAS group) exhibited significantly greater rs-FC of the mPFC seed with the thalamus, caudate and putamen. Additionally, the strength of rs-FC of the mPFC seed with these regions was positively associated with the MEDAS scores across groups in both crude and adjusted models. There were no significant associations between the strength of rs-FC of the mPFC seed with the cluster of voxels with the thalamus, caudate, and putamen and ruminative thinking.

DISCUSSION

This work shows that healthy dietary patterns are associated with rs-FC in the frontal-subcortical circuitry in healthy volunteers. Considering the implications of the dysregulation of this circuity, adhering to healthy dietary patterns may offer a promising alternative/complementary method to improve CMDs, cognitive control, and food choices.

Dairy consumption and risk of prediabetes and type 2 diabetes in the Fenland study

BACKGROUND & AIMS

Limited observational evidence suggests that a higher intake of high-fat dairy may be associated with lower prediabetes risk, while opposite associations have been observed for low-fat milk intake. This study aimed to examine associations between baseline and changes in dairy consumption, risk of prediabetes, and glycaemic status.

METHODS

7521 participants from the prospective UK Fenland study were included (mean age 48.7 ± 2.0 years, 51.9 % female). Dairy intake was measured using self-reported food frequency questionnaires. Associations with prediabetes risk and glycaemic status were analysed using Poisson regression models adjusted for social demographics, health behaviours, family history of diabetes and food group intake.

RESULTS

At a mean follow-up of 6.7 ± 2.0 years, 290 participants developed prediabetes (4.3 %). Most dairy products were not significantly associated with prediabetes risk. A higher baseline intake of high-fat dairy (RRservings/day 1.20, 95%CI 1.03-1.39) and high-fat milk (RRservings/day 1.22, 1.01-1.47) were associated with higher prediabetes risk. Conversely, low-fat milk was associated with lower prediabetes risk (RRservings/day 0.86, 0.75-0.98). In the analyses evaluating dietary changes over time, increases in high-fat milk were inversely associated with risk of progressing from normoglycaemia to prediabetes or type 2 diabetes (RRservings/day 0.86, 95%CI 0.75-0.99).

CONCLUSIONS

This population-based study showed that most dairy products are not associated with prediabetes risk or progression in glycaemic status. Positive associations of high-fat dairy, high-fat milk, and the inverse association of low-fat milk with prediabetes risk found were inconsistent with prior literature and suggestive of the need for future research on environmental, behavioural, and biological factors that explain the available evidence.

Combined associations of physical activity, diet quality and their changes over time with mortality: findings from the EPIC-Norfolk study, United Kingdom

BACKGROUND

Physical activity (PA) and diet quality have each been shown to be inversely associated with mortality but their combined impact on longevity has been less explored, particularly when considering their changes over time. This study aimed to examine the separate and combined associations of PA, diet quality and their changes over time with mortality outcomes.

METHODS

A prospective cohort study was performed on 9349 adults aged 40 to 79 years from the population-based European Prospective Investigation into Cancer in Norfolk Study, with repeated measurements of PA and diet (from 1993 till 2004) and subsequent follow-up till 2022 (median follow-up 18.8 years). Validated questionnaires were used to derive physical activity energy expenditure (PAEE) as a proxy of total PA and adherence to the Mediterranean diet score (MDS, range 0-15 points) as an indicator of overall diet quality, and their changes over time (∆PAEE and ∆MDS). Cox regression models adjusted for potential confounders and mediators were used to estimate hazard ratios (HRs) and 95% CIs.

RESULTS

Over 149,681 person-years of follow-up, there were 3534 deaths. In adjusted models, for each 1-SD difference in baseline PAEE (4.64 kJ/kg/day), ∆PAEE (0.65 kJ/kg/day per year), baseline MDS (1.30 points) and ∆MDS (0.32 points per year), HRs (95% CI) for all-cause mortality were 0.90 (0.86 to 0.94), 0.89 (0.85 to 0.93), 0.95 (0.91 to 0.99) and 0.93 (0.90 to 0.97), respectively. Compared with participants with sustained low PAEE (< 5 kJ/kg/day) and low MDS (< 8.5 points), those with sustained high PAEE and high MDS had lower all-cause mortality (HR 0.78; 95% CI: 0.68-0.91), as did those who improved both PAEE and MDS (0.60; 0.44-0.82). There was no evidence of interaction between PA and diet quality exposures on mortality risk. Population impact estimates suggested that if all participants had maintained high levels of PA and diet quality consistently, cumulative adjusted mortality rate would have been 8.8% (95% CI: 2.4 to 15.3%) lower.

CONCLUSIONS

These findings suggest that adopting and maintaining higher levels of PA and diet quality are associated with lower mortality. Significant public health benefits could be realised by enabling active living and healthy eating through adulthood.

Mapping biological influences on the human plasma proteome beyond the genome

Broad-capture proteomic platforms now enable simultaneous assessment of thousands of plasma proteins, but most of these are not actively secreted and their origins are largely unknown. Here we integrate genomic with deep phenomic information to identify modifiable and non-modifiable factors associated with 4,775 plasma proteins in ~8,000 mostly healthy individuals. We create a data-driven map of biological influences on the human plasma proteome and demonstrate segregation of proteins into clusters based on major explanatory factors. For over a third (N = 1,575) of protein targets, joint genetic and non-genetic factors explain 10-77% of the variation in plasma (median 19.88%, interquartile range 14.01-31.09%), independent of technical factors (median 2.48%, interquartile range 0.78-6.41%). Together with genetically anchored causal inference methods, our map highlights potential causal associations between modifiable risk factors and plasma proteins for hundreds of protein-disease associations, for example, COL6A3, which possibly mediates the association between reduced kidney function and cardiovascular disease. We provide a map of biological and technical influences on the human plasma proteome to help contextualize findings from proteomic studies.

Ultra-processed food and drink consumption and lipoprotein subclass profiles: A cross-sectional study of a middle-to older-aged population

BACKGROUND AND AIMS

Studies have consistently demonstrated associations between ultra-processed food and drink (UPFD) consumption and non-communicable diseases. However, there is a lack of data investigating relationships between UPFD intake and intermediate cardiometabolic disease markers. In this study we explored UPFD associations with lipoprotein subclasses.

METHODS

This was a cross-sectional study of 1986 middle-to older-aged men and women randomly selected from a large primary care centre. The percentage contribution of UPFDs to total energy intake was calculated for each participant using the NOVA classification. Lipoprotein particle subclass concentrations and size were determined using nuclear magnetic resonance spectroscopy. Correlation and multivariate-adjusted linear regression analyses were performed to examine UPFD intake relationships with lipoprotein subclasses.

RESULTS

In fully adjusted regression models, higher UPFD consumption was associated with reduced high-density lipoprotein (HDL) cholesterol concentrations (β = -0.024, p = 0.001), large low-density lipoprotein (LDL) levels (β = -18.645, p = 0.002), total and medium HDL concentrations (β = -0.328, p = 0.012; β = -0.510, p < 0.001), smaller LDL and HDL size (β = -0.026, p = 0.023; β = -0.023, p = 0.024), and increased medium very low-density lipoprotein levels (β = 0.053, p = 0.022), small LDL and HDL concentrations (β = 20.358, p = 0.02; β = 0.336, p = 0.011), and higher lipoprotein insulin resistance scores (β = 0.048, p = 0.012), reflecting greater lipoprotein-related insulin resistance.

CONCLUSIONS

Findings from this research suggest that increased intake of UPFDs is associated with a more pro-atherogenic, insulin-resistant metabolic profile in middle-to older-aged adults which may be a potential mechanism underlying reported associations between UPFD consumption and chronic disease risk and mortality.

Dietary inflammation, sleep and mental health in the United Kingdom and Japan: A comparative cross‐sectional study

Diet has been repeatedly shown to affect mental and sleep health outcomes. However, it is well known that there are cross‐cultural differences in dietary practices as well as the prevalence of mental and sleep health outcomes. Given that the dietary inflammatory potential of diets has been linked to mental and sleep health outcomes, in the current study we sought to assess the inflammatory status of habitual diets and examine its relationship with mental and sleep health outcomes in both the United Kingdom and Japan. Our aim was to determine if the associations between the dietary inflammation index (DII) score and these health outcomes could elucidate any potential cross‐cultural differences in health. Online survey data was collected from 602 participants (aged 18–40 years) in the United Kingdom (n = 288) and Japan (n = 314). Participants self‐reported their dietary intakes, as well as current mental health and sleep patterns. The DII score was calculated (score range − 2.79 to 3.49) We found that although participants in the United Kingdom reported better overall mental wellbeing, participants in Japan reported less severe depression, anxiety and stress and better subjective sleep quality, less sleep disturbances and daytime dysfunction, despite sleeping shorter, and a better adherence to an anti‐inflammatory diet. Moreover, across the United Kingdom and Japan, adherence to more anti‐inflammatory diets predicted higher levels of subjective sleep quality, fewer sleep disturbances, less use of sleep medicine and less daytime dysfunction. In conclusion, there are several differences between mental and sleep health outcomes in the United Kingdom and Japan, which could be attributable to the inflammatory potential of respective regional diets. Future studies are warranted to examine the mental and sleep health benefits of adhering to anti‐inflammatory traditional Japanese diets in clinical and subclinical cohorts.

The Dietary Inflammatory Index and Its Associations with Biomarkers of Nutrients with Antioxidant Potential, a Biomarker of Inflammation and Multiple Long-Term Conditions

We aimed to validate the Dietary Inflammatory Index (DII®) and assess the cross-sectional associations between the DII® and multiple long-term conditions (MLTCs) and biomarker concentrations and MLTCs using data from the European Prospective Investigation into Cancer (EPIC-Norfolk) study (11,113 men and 13,408 women). The development of MLTCs is associated with low-grade chronic inflammation, and ten self-reported conditions were selected for our MLTC score. Data from a validated FFQ were used to calculate energy-adjusted DII® scores. High-sensitivity C-reactive protein (hs-CRP) and circulating vitamins A, C, E, β-carotene and magnesium were available. Micronutrient biomarker concentrations were significantly lower as the diet became more pro-inflammatory (p-trend < 0.001), and hs-CRP concentrations were significantly higher in men (p-trend = 0.006). A lower DII® (anti-inflammatory) score was associated with 12-40% higher odds of MLTCs. Lower concentrations of vitamin C and higher concentrations of hs-CRP were associated with higher odds of MLTCs. The majority of the associations in our study between MLTCs, nutritional biomarkers, hs-CRP and the DII® were as expected, indicating that the DII® score has criterion validity. Despite this, a more anti-inflammatory diet was associated with higher odds of MLTCs, which was unexpected. Future studies are required to better understand the associations between MLTCs and the DII®.

Methods and participant characteristics in the Cancer Risk in Vegetarians Consortium: a cross-sectional analysis across 11 prospective studies

BACKGROUND

The associations of vegetarian diets with risks for site-specific cancers have not been estimated reliably due to the low number of vegetarians in previous studies. Therefore, the Cancer Risk in Vegetarians Consortium was established. The aim is to describe and compare the baseline characteristics between non-vegetarian and vegetarian diet groups and between the collaborating studies.

METHODS

We harmonised individual-level data from 11 prospective cohort studies from Western Europe, North America, South Asia and East Asia. Comparisons of food intakes, sociodemographic and lifestyle factors were made between diet groups and between cohorts using descriptive statistics.

RESULTS

2.3 million participants were included; 66% women and 34% men, with mean ages at recruitment of 57 (SD: 7.8) and 57 (8.6) years, respectively. There were 2.1 million meat eaters, 60,903 poultry eaters, 44,780 pescatarians, 81,165 vegetarians, and 14,167 vegans. Food intake differences between the diet groups varied across the cohorts; for example, fruit and vegetable intakes were generally higher in vegetarians than in meat eaters in all the cohorts except in China. BMI was generally lower in vegetarians, particularly vegans, except for the cohorts in India and China. In general, but with some exceptions, vegetarians were also more likely to be highly educated and physically active and less likely to smoke. In the available resurveys, stability of diet groups was high in all the cohorts except in China.

CONCLUSIONS

Food intakes and lifestyle factors of both non-vegetarians and vegetarians varied markedly across the individual cohorts, which may be due to differences in both culture and socioeconomic status, as well as differences in questionnaire design. Therefore, care is needed in the interpretation of the impacts of vegetarian diets on cancer risk.

Validity and reproducibility of the Prime Diet Quality Score (PDQS) against a four-day food diary in adults at risk of cardiovascular disease on the island of Ireland

There is an increasing need for valid, rapid diet screening tools. A significant association between the Prime Diet Quality Score (PDQS) and reduced risk of cardiovascular disease (CVD) has been demonstrated in the US but evidence of its use in Europe is lacking. The aim of this study was to amend the PDQS for a UK/Irish population and determine validity and reliability in those at risk of CVD. Participants were recruited via online adverts across the island of Ireland. The PDQS was amended for a UK/Irish population and participants completed PDQS and reference measure (4-day food diary (FD)) on two occasions. PDQS score was calculated directly from PDQS and indirectly from FDs. Validity was determined using Spearman correlation coefficients (SCCs) (r), intraclass correlation coefficients (ICCs) and weighted kappa. Reliability was determined using SCCs (r), ICCs, weighted kappa and coefficient of variation. 'Data were available for n = 115 (Month 0) and n = 108 (Month 3) participants for validity and n = 110 for reliability assessment (PDQS completed at both timepoints)'. PDQS score from PDQS was significantly correlated with PDQS score from FDs at months 0 (r = 0.59, P < 0.01) and 3 (r = 0.65, P < 0.01), with similar associations observed via ICCs. Weighted kappa indicated moderate agreement. PDQS score at month 0 was significantly correlated with PDQS score at month 3 (r = 0.78, P < 0.01), with similar associations observed via ICCs. Weighted kappa indicated moderate agreement. Results indicate that the amended PDQS is a valid and reliable tool to determine diet quality in a UK/Irish population at risk of CVD.

The Nutri-Score nutrition label: Associations between the underlying nutritional profile of foods and lipoprotein particle subclass profiles in adults

BACKGROUND AND AIMS

Lipoprotein particle concentrations and size are associated with increased risk for atherosclerosis and premature cardiovascular disease. Certain dietary behaviours may be cardioprotective and public health strategies are needed to guide consumers' dietary choices and help prevent diet-related disease. The Food Standards Agency nutrient profiling system (FSAm-NPS) constitutes the basis of the five-colour front-of-pack Nutri-Score labelling system. No study has examined FSAm-NPS index associations with a wide range of lipoprotein particle subclasses.

METHODS

This was a cross-sectional study of 2006 middle-to older-aged men and women randomly selected from a large primary care centre. Individual participant FSAm-NPS dietary scores were derived from validated food frequency questionnaires. Lipoprotein particle subclass concentrations and size were determined using nuclear magnetic resonance spectroscopy. Multivariate-adjusted linear regression analyses were performed to examine FSAm-NPS relationships with lipoprotein particle subclasses.

RESULTS

In fully adjusted models which accounted for multiple testing, higher FSAm-NPS scores, indicating poorer dietary quality, were positively associated with intermediate-density lipoprotein (β = 0.096, p = 0.005) and small high-density lipoprotein (HDL) (β = 0.492, p = 0.006) concentrations, a lipoprotein insulin resistance score (β = 0.063, p = 0.02), reflecting greater lipoprotein-related insulin resistance, and inversely associated with HDL size (β = -0.030, p = 0.045).

CONCLUSIONS

A higher FSAm-NPS score is associated with a less favourable lipoprotein particle subclass profile in middle-to older-aged adults which may be a potential mechanism underlying reported health benefits of a healthy diet according to Nutri-Score rating.

A single-blinded, randomized, parallel intervention to evaluate genetics and omics-based personalized nutrition in general population via an e-commerce tool: The PREVENTOMICS e-commerce study

BACKGROUND

Personalized nutrition (PN) has been proposed as a strategy to increase the effectiveness of dietary recommendations and ultimately improve health status.

OBJECTIVES

We aimed to assess whether including omics-based PN in an e-commerce tool improves dietary behavior and metabolic profile in general population.

METHODS

A 21-wk parallel, single-blinded, randomized intervention involved 193 adults assigned to a control group following Mediterranean diet recommendations (n = 57, completers = 36), PN (n = 70, completers = 45), or personalized plan (PP, n = 68, completers = 53) integrating a behavioral change program with PN recommendations. The intervention used metabolomics, proteomics, and genetic data to assist participants in creating personalized shopping lists in a simulated e-commerce retailer portal. The primary outcome was the Mediterranean diet adherence screener (MEDAS) score; secondary outcomes included biometric and metabolic markers and dietary habits.

RESULTS

Volunteers were categorized with a scoring system based on biomarkers of lipid, carbohydrate metabolism, inflammation, oxidative stress, and microbiota, and dietary recommendations delivered accordingly in the PN and PP groups. The intervention significantly increased MEDAS scores in all volunteers (control-3 points; 95% confidence interval [CI]: 2.2, 3.8; PN-2.7 points; 95% CI: 2.0, 3.3; and PP-2.8 points; 95% CI: 2.1, 3.4; q < 0.001). No significant differences were observed in dietary habits or health parameters between PN and control groups after adjustment for multiple comparisons. Nevertheless, personalized recommendations significantly (false discovery rate < 0.05) and selectively enhanced the scores calculated with biomarkers of carbohydrate metabolism (β: -0.37; 95% CI: -0.56, -0.18), oxidative stress (β: -0.37; 95% CI: -0.60, -0.15), microbiota (β: -0.38; 95% CI: -0.63, -0.15), and inflammation (β: -0.78; 95% CI: -1.24, -0.31) compared with control diet.

CONCLUSIONS

Integration of personalized strategies within an e-commerce-like tool did not enhance adherence to Mediterranean diet or improved health markers compared with general recommendations. The metabotyping approach showed promising results and more research is guaranteed to further promote its application in PN. This trial was registered at clinicaltrials.gov as NCT04641559 (https://clinicaltrials.gov/study/NCT04641559?cond=NCT04641559&rank=1).

Lifestyle factors and BMI attenuate relationships between biomarkers of inflammation and depressive symptoms and well-being: A cross-sectional study

Background

Mental disorders are a growing public health concern and evidence has linked chronic low-grade inflammation with depression and well-being. Research also suggests that certain modifiable lifestyle factors such as smoking, alcohol use, physical activity, diet quality and BMI are related to psychological health. These may modulate the relationship between low-grade inflammation and mental health conditions. In this study we examined inflammatory biomarker associations with two psychological health scores and investigated whether relationships are influenced by lifestyle factors and BMI.

Methods

This was a cross-sectional study of 1824 middle-to older-aged men and women randomly selected from a large primary care centre. Depressive symptoms and well-being were assessed using the 20-item Centre for Epidemiologic Studies Depression (CES-D) Scale and the World Health Organization-Five (WHO-5) Well-Being Index. Linear regression analyses were performed to examine depression and well-being score relationships with six inflammatory biomarkers, and a composite inflammatory biomarker score, adjusting for demographic characteristics, health conditions, lifestyle factors and BMI.

Results

Depression and well-being score associations with complement component 3 (CES-D only) c-reactive protein, interleukin 6, leptin, white blood cell counts, neutrophils and the inflammatory biomarker score were observed. These relationships survived adjustment for demographic variables and health conditions but were attenuated in models which included lifestyle factors and BMI. In final models, only leptin (β = 0.566, p = 0.018) and inflammatory score (β = 0.137, p = 0.004) associations with the CES-D score remained.

Conclusions

These findings suggest that the relationship between systemic low-grade inflammation and depressive symptoms and well-being may be largely explained by lifestyle factors and adiposity, highlighting the potential importance of promoting a healthy lifestyle in the treatment of depressive disorders.

Assessing Performance of Contemporary Plant-Based Diets against the UK Dietary Guidelines: Findings from the Feeding the Future (FEED) Study

Uncertainty remains about the composition of contemporary plant-based diets and whether they provide recommended nutrient intakes. We established Feeding the Future (FEED), an up-to-date online cohort of UK adults following different plant-based diets and diets containing meat and fish. We recruited 6342 participants aged 18-99 [omnivores (1562), flexitarians (1349), pescatarians (568), vegetarians (1292), and vegans (1571)] between February 2022 and December 2023, and measured diet using a food frequency questionnaire and free text. We compared personal characteristics and dietary intakes between diet groups and assessed compliance with dietary guidelines. Most participants met UK dietary recommendations for fruit and vegetables, sodium, and protein, although protein intakes were lowest among vegetarians and vegans. Omnivores did not meet the fibre recommendation and only vegans met the saturated fat recommendation. All diet groups exceeded the free sugars recommendation. Higher proportions of vegetarians and vegans were below the estimated average requirements (EARs) for zinc, iodine, selenium, and, in vegans, vitamins A and B12, whereas calcium intakes were similar across the diet groups. People following plant-based diets showed good compliance with most dietary targets, and their risk for inadequate intakes of certain nutrients might be mitigated by improved dietary choices and/or food fortification.

UPDATE trial: investigating the effects of ultra-processed versus minimally processed diets following UK dietary guidance on health outcomes: a protocol for an 8-week community-based cross-over randomised controlled trial in people with overweight or obesity, followed by a 6-month behavioural intervention

INTRODUCTION

Obesity increases the risk of morbidity and mortality. A major driver has been the increased availability of ultra-processed food (UPF), now the main UK dietary energy source. The UK Eatwell Guide (EWG) provides public guidance for a healthy balanced diet but offers no UPF guidance. Whether a healthy diet can largely consist of UPFs is unclear. No study has assessed whether the health impact of adhering to dietary guidelines depends on food processing. Furthermore, our study will assess the impact of a 6-month behavioural support programme aimed at reducing UPF intake in people with overweight/obesity and high UPF intakes.

METHODS AND ANALYSIS

UPDATE is a 2×2 cross-over randomised controlled trial with a 6-month behavioural intervention. Fifty-five adults aged ≥18, with overweight/obesity (≥25 to <40 kg/m2), and ≥50% of habitual energy intake from UPFs will receive an 8-week UPF diet and an 8-week minimally processed food (MPF) diet delivered to their home, both following EWG recommendations, in a random order, with a 4-week washout period. All food/drink will be provided. Participants will then receive 6 months of behavioural support to reduce UPF intake. The primary outcome is the difference in weight change between UPF and MPF diets from baseline to week 8. Secondary outcomes include changes in diet, waist circumference, body composition, heart rate, blood pressure, cardiometabolic risk factors, appetite regulation, sleep quality, physical activity levels, physical function/strength, well-being and aspects of behaviour change/eating behaviour at 8 weeks between UPF/MPF diets, and at 6-month follow-up. Quantitative assessment of changes in brain MRI functional resting-state connectivity between UPF/MPF diets, and qualitative analysis of the behavioural intervention for feasibility and acceptability will be undertaken.

ETHICS AND DISSEMINATION

Sheffield Research Ethics Committee approved the trial (22/YH/0281). Peer-reviewed journals, conferences, PhD thesis and lay media will report results.

TRIAL REGISTRATION NUMBER

NCT05627570.

Chronic and postprandial effect of blueberries on cognitive function, alertness, and mood in participants with metabolic syndrome - results from a six-month, double-blind, randomized controlled trial

BACKGROUND

Anthocyanin and blueberry intakes positively associated with cognitive function in population-based studies and cognitive benefits in randomized controlled trials of adults with self-perceived or clinical cognitive dysfunction. To date, adults with metabolic syndrome (MetS) but without cognitive dysfunction are understudied.

OBJECTIVES

Cognitive function, mood, alertness, and sleep quality were assessed as secondary end points in MetS participants, postprandially (>24 h) and following 6-mo blueberry intake.

METHODS

A double-blind, randomized controlled trial was conducted, assessing the primary effect of consuming freeze-dried blueberry powder, compared against an isocaloric placebo, on cardiometabolic health >6 mo and a 24 h postprandial period (at baseline). In this secondary analysis of the main study, data from those completing mood, alertness, cognition, and sleep assessments are presented (i.e., n = 115 in the 6 mo study, n = 33 in the postprandial study), using the following: 1) Bond-Lader self-rated scores, 2) electronic cognitive battery (i.e., testing attention, working memory, episodic memory, speed of memory retrieval, executive function, and picture recognition), and 3) the Leeds Sleep Evaluation Questionnaire. Urinary and serum anthocyanin metabolites were quantified, and apolipoprotein E genotype status was determined.

RESULTS

Postprandial self-rated calmness significantly improved after 1 cup of blueberries (P = 0.01; q = 0.04; with an 11.6% improvement compared with baseline between 0 and 24 h for the 1 cup group), but all other mood, sleep, and cognitive function parameters were unaffected after postprandial and 6-mo blueberries. Across the ½ and 1 cup groups, microbial metabolites of anthocyanins and chlorogenic acid (i.e., hydroxycinnamic acids, benzoic acids, phenylalanine derivatives, and hippuric acids) and catechin were associated with favorable chronic and postprandial memory, attention, executive function, and calmness.

CONCLUSIONS

Although self-rated calmness improved postprandially, and significant cognition-metabolite associations were identified, our data did not support strong cognitive, mood, alertness, or sleep quality improvements in MetS participants after blueberry intervention. This trial was registered at clinicaltrials.gov as NCT02035592.

Anthropometric measures, predicted visceral adipose tissue and biomarkers of chronic inflammation

BACKGROUND

Evidence has linked low-grade systemic inflammation and visceral adipose tissue (VAT) with development of chronic conditions. Cytokines and select proteins released by VAT may promote a low-grade inflammatory response. A number of equations have been developed to estimate VAT levels. In this study, we compared predicted VAT equation relationships with biomarkers of inflammation.

METHODS

This was a cross-sectional study of 2038 men and women aged 46-73 years. Correlation and linear regression analyses were performed to examine inflammatory biomarker relationships with four commonly assessed anthropometric measures and 10 predicted VAT equations.

RESULTS

Compared with anthropometric measures, predicted VAT equations were found to explain a greater proportion of variance in CRP (R2  = .075, p = .001), IL-6 (R2  = .060, p = .001), TNF-α (R2  = .017, p = .005), resistin (R2  = .011, p = .012), monocyte (R2  = .027, p = .001), eosinophil (R2  = .012, p = .01) and basophil (R2  = .015, p = .002) levels in males, and a greater variance in concentrations of C3 (R2  = .175, p = .001), IL-6 (R2  = .090, p = .001), TNF-α (R2  = .036, p = .001), adiponectin (R2  = .121, p = .001), the adiponectin-to-leptin ratio (R2  = .444, p = .001), resistin (R2  = .025, p = .001), white blood cell count (R2  = .057, p = .001), neutrophils (R2  = .061, p = .001) and lymphocytes (R2  = .020, p = .001) in females.

CONCLUSION

Equations for assessing VAT levels might be useful to characterise metabolic health. Further studies that examine predicted VAT relationships with disease and mortality outcomes are warranted.

Diet patterns and cognitive performance in a UK Female Twin Registry (TwinsUK)

BACKGROUND

Plant-based diets may provide protection against cognitive decline and Alzheimer's disease, but observational data have not been consistent. Previous studies include early life confounding from socioeconomic conditions and genetics that are known to influence both cognitive performance and diet behaviour. This study investigated associations between Mediterranean (MED) diet and MIND diets and cognitive performance accounting for shared genotype and early-life environmental exposures in female twins.

METHODS

Diet scores were examined in 509 female twins enrolled in TwinsUK study. The Cambridge Neuropsychological Test Automated Battery was used to assess cognition at baseline and 10 years later (in n = 275). A co-twin case-control study for discordant monozygotic (MZ) twins examined effects of diet on cognitive performance independent of genetic factors. Differences in relative abundance of taxa at 10-year follow-up were explored in subsamples.

RESULTS

Each 1-point increase in MIND or MED diet score was associated with 1.75 (95% CI: - 2.96, - 0.54, p = 0.005 and q = 0.11) and 1.67 (95% CI: - 2.71, - 0.65, p = 0.002 and q = 0.02) fewer respective errors in paired-associates learning. Within each MZ pair, the twin with the high diet score had better preservation in spatial span especially for MED diet (p = 0.02). There were no differences between diet scores and 10-year change in the other cognitive tests. MIND diet adherence was associated with higher relative abundance of Ruminococcaceae UCG-010 (0.30% (95% CI 0.17, 0.62), q = 0.05) which was also associated with less decline in global cognition over 10 years (0.22 (95% CI 0.06, 0.39), p = 0.01).

CONCLUSIONS

MIND or MED diets could help to preserve some cognitive abilities in midlife, particularly episodic and visuospatial working memory. Effects may be mediated by high dietary fibre content and increased abundance of short-chain fatty acid producing gut bacteria. Longer follow-up with repeated measures of cognition will determine whether diet can influence changes in cognition occurring in older age.

Development of a novel (poly)phenol-rich diet score and its association with urinary (poly)phenol metabolites

Background: Estimating (poly)phenol intake is challenging due to inadequate dietary assessment tools and limited food content data. Currently, a priori diet scores to characterise (poly)phenol-rich diets are lacking. This study aimed to develop a novel (poly)phenol-rich diet score (PPS) and explore its relationship with circulating (poly)phenol metabolites. Methods: A total of 543 healthy free-living participants aged 18-80 years completed a food frequency questionnaire (FFQ) (EPIC-Norfolk) and provided 24 h urine samples. The PPS was developed based on the relative intake (quintiles) of 20 selected (poly)phenol-rich food items abundant in the UK diet, including tea, coffee, red wine, whole grains, chocolate and cocoa products, berries, apples and juice, pears, grapes, plums, citrus fruits and juice, potatoes and carrots, onions, peppers, garlic, green vegetables, pulses, soy and soy products, nuts, and olive oil. Foods included in the PPS were chosen based on their (poly)phenol content, main sources of (poly)phenols, and consumption frequencies in the UK population. Associations between the PPS and urinary phenolic metabolites were investigated using linear models adjusting energy intake and multiple testing (FDR adjusted p < 0.05). Result: The total PPS ranged from 25 to 88, with a mean score of 54. A total of 51 individual urinary metabolites were significantly associated with the PPS, including 39 phenolic acids, 5 flavonoids, 3 lignans, 2 resveratrol and 2 other (poly)phenol metabolites. The total (poly)phenol intake derived from FFQs also showed a positive association with PPS (stdBeta 0.32, 95% CI (0.24, 0.40), p < 0.01). Significant positive associations were observed in 24 of 27 classes and subclasses of estimated (poly)phenol intake and PPS, with stdBeta values ranging from 0.12 (0.04, 0.20) for theaflavins/thearubigins to 0.43 (0.34, 0.51) for flavonols (p < 0.01). Conclusion: High adherence to the PPS diet is associated with (poly)phenol intake and urinary biomarkers, indicating the utility of the PPS to characterise diets rich in (poly)phenols at a population level.

An Examination of the Associations between Nutritional Composition, Social Jet Lag and Temporal Sleep Variability in Young Adults

While dietary intake has previously been related to various indices of poor sleep (e.g., short sleep duration, poor sleep quality), to date, few studies have examined chrononutrition from the perspectives of the relationship between dietary intake and social jet lag and temporal sleep variability. Moreover, recently it has been suggested that previous methods of measuring social jet lag have the potential to lead to large overestimations. Together, this precludes a clear understanding of the role of nutritional composition in the pathophysiology of poor sleep, via social jet lag and temporal sleep variability, or vice versa. The aim of the present study was to determine the relationships between nutrient intake and social jet lag (using a revised index, taking account of intention to sleep and sleep onset and offset difficulties), and temporal sleep variability. Using a cross-sectional survey, 657 healthy participants (mean age 26.7 ± 6.1 years), without sleep disorders, were recruited via an online platform and completed measures of weekly dietary intake, social jet lag, temporal sleep variability, stress/sleep reactivity and mood. Results showed limited associations between nutritional composition and social jet lag. However, levels of temporal sleep variability were predicted by consumption of polyunsaturated fats, sodium, chloride and total energy intake. The results suggest further examinations of specific nutrients are warranted in a first step to tailoring interventions to manage diet and temporal variabilities in sleep patterns.

Lower systemic nitric oxide bioactivity, cerebral hypoperfusion and accelerated cognitive decline in formerly concussed retired rugby union players

NEW FINDINGS

What is the central question of this study? What are the molecular, cerebrovascular and cognitive biomarkers of retired rugby union players with concussion history? What is the main finding and its importance? Retired rugby players compared with matched controls exhibited lower systemic nitric oxide bioavailability accompanied by lower middle cerebral artery velocity and mild cognitive impairment. Retired rugby players are more susceptible to accelerated cognitive decline.

ABSTRACT

Following retirement from sport, the chronic consequences of prior-recurrent contact are evident and retired rugby union players may be especially prone to accelerated cognitive decline. The present study sought to integrate molecular, cerebrovascular and cognitive biomarkers in retired rugby players with concussion history. Twenty retired rugby players aged 64 ± 5 years with three (interquartile range (IQR), 3) concussions incurred over 22 (IQR, 6) years were compared to 21 sex-, age-, cardiorespiratory fitness- and education-matched controls with no prior concussion history. Concussion symptoms and severity were assessed using the Sport Concussion Assessment Tool. Plasma/serum nitric oxide (NO) metabolites (reductive ozone-based chemiluminescence), neuron specific enolase, glial fibrillary acidic protein and neurofilament light-chain (ELISA and single molecule array) were assessed. Middle cerebral artery blood velocity (MCAv, doppler ultrasound) and reactivity to hyper/hypocapnia (CVR CO 2 hyper ${\mathrm{CVR}}_{{\mathrm{CO}}_{\mathrm{2}}{\mathrm{hyper}}}$ /CVR CO 2 hypo ${\mathrm{CVR}}_{{\mathrm{CO}}_{\mathrm{2}}{\mathrm{hypo}}}$ ) were assessed. Cognition was determined using the Grooved Pegboard Test and Montreal Cognitive Assessment. Players exhibited persistent neurological symptoms of concussion (U = 109(41) , P = 0.007), with increased severity compared to controls (U = 77(41) , P < 0.001). Lower total NO bioactivity (U = 135(41) , P = 0.049) and lower basal MCAv were apparent in players (F2,39  = 9.344, P = 0.004). This was accompanied by mild cognitive impairment (P = 0.020, 95% CI, -3.95 to -0.34), including impaired fine-motor coordination (U = 141(41) , P = 0.021). Retired rugby union players with history of multiple concussions may be characterised by impaired molecular, cerebral haemodynamic and cognitive function compared to non-concussed, non-contact controls.

Association of dietary flavan-3-ol intakes with plasma phenyl-γ-valerolactones: analysis from the TUDA cohort of healthy older adults

BACKGROUND

Dietary polyphenols, including flavan-3-ols (F3O), are associated with better health outcomes. The relationship of plasma phenyl-γ-valerolactones (PVLs), the products of colonic bacterial metabolism of F3O, with dietary intakes is unclear.

OBJECTIVES

To investigate whether plasma PVLs are associated with self-reported intakes of total F3O and procyanidins+(epi)catechins.

DESIGN

We measured 9 PVLs by uHPLC-MS-MS in plasma from adults (>60y) in the Trinity-Ulster-Department of Agriculture (TUDA study (2008 to 2012; n=5186) and a follow-up subset (2014 to 2018) with corresponding dietary data (n=557). Dietary (poly)phenols collected by FFQ were analyzed using Phenol-Explorer.

RESULTS

Mean (95% confidence interval [CI]) intakes were estimated as 2283 (2213, 2352) mg/d for total (poly)phenols, 674 (648, 701) for total F3O, and 152 (146, 158) for procyanidins+(epi)catechins. Two PVL metabolites were detected in plasma from the majority of participants, 5-(hydroxyphenyl)-γ-VL-sulfate (PVL1) and 5-(4'-hydroxyphenyl)-γ-VL-3'-glucuronide (PVL2). The 7 other PVLs were detectable only in 1-32% of samples. Self-reported intakes (mg/d) of F3O (r = 0.113, P = 0.017) and procyanidin+(epi)catechin (r = 0.122, P = 0.010) showed statistically significant correlations with the sum of PVL1 and PVL 2 (PVL1+2). With increasing intake quartiles (Q1-Q4), mean (95% CI) PVL1+2 increased; from 28.3 (20.8, 35.9) nmol/L in Q1 to 45.2 (37.2, 53.2) nmol/L in Q4; P = 0.025, for dietary F3O, and from 27.4 (19.1, 35.8) nmol/L in Q1 to 46.5 (38.2, 54.9) nmol/L in Q4; P = 0.020, for procyanidins+(epi)catechins.

CONCLUSIONS

Of 9 PVL metabolites investigated, 2 were detected in most samples and were weakly associated with intakes of total F3O and procyanidins+(epi)catechins. Future controlled feeding studies are required to validate plasma PVLs as biomarkers of these dietary polyphenols.

Personality, dietary identity, mental and sleep health in vegans and vegetarians: A preliminary cross-sectional study

Background and Aims

Plant-based diets have gained popularity over the past decade. However, research regarding mental and sleep health benefits of following plant-based diets are conflicting. As there are associations between mental/sleep health and various personality traits, and personality may differ between individuals who follow different diets, in this preliminary study, we examined the associations between mental and sleep health and (i) personality and (ii) dietary identity in individuals who follow vegan and vegetarian diets.

Methods

Cross-sectional data on sociodemographic, personality traits, dietarian identity, overall mental health, depression, anxiety, stress, and sleep quality were collected from 57 vegan/vegetarian participants between the ages of 18-40.

Results

After controlling for various sociodemographic and lifestyle factors, linear regression models revealed that (i) higher dietarian private regard was a significant predictor of better overall mental health, (ii) lower levels of extraversion and higher levels of empathy predicted depression, (iii) higher levels of neuroticism and empathy predicted anxiety, (iv) higher levels of neuroticism, dietarian centrality, and neuroticism × centrality predicted stress, (v) higher levels of conscientiousness, lower levels of dietarian centrality, but higher levels of personal motivation and dietary strictness, as well as conscientiousness × centrality, conscientiousness × personal motivation, and conscientiousness × strictness predicted better sleep quality.

Conclusions

These preliminary findings suggest that not only personality traits, but also dietary identity was indeed related to mental and sleep health in individuals who follow plant-based diets.

Dietary Intervention Improves Gastrointestinal Symptoms after Treatment of Cancer in the Pelvic Organs

Gastrointestinal (GI) symptoms are common in patients receiving radiotherapy, chemotherapy, and/or surgery for cancer in the pelvic organs. The aim of the present prospective cohort study was to report the efficacy of dietary intervention in patients with chronic GI sequelae to treatment of cancer in pelvic organs and insufficient symptomatic effect of medical treatment. Eighty-eight patients were offered specialist dietitian guidance. Gastrointestinal symptoms and quality of life were assessed before and after intervention by validated questionnaires. The main dietary interventions were low-fat diet (n = 44; 50%), modification of dietary fiber content (n = 19; 33%), dietary restrictions with a low-FODMAP (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) diet (n = 18; 20%), gluten-free diet (n = 1; 1%), and other dietary advice (n = 6; 7%). Compared to baseline, dietary intervention improved quality of life (EQ5D scale) (p < 0.01), bowel function for the last four weeks (p < 0.02), stool frequency (p < 0.03), constipation (p < 0.05), incomplete rectal emptying at defecation (p < 0.02), and performing usual activities (p < 0.0). In conclusion, this observational study using tailored dietary intervention showed that symptoms can be reduced and quality of life can be improved in patients with chronic GI sequelae following treatment of cancer in the pelvic organs not responding sufficiently to medical treatment.

Vegans, vegetarians, fish-eaters and meat-eaters in the UK show discrepant environmental impacts

Modelled dietary scenarios often fail to reflect true dietary practice and do not account for variation in the environmental burden of food due to sourcing and production methods. Here we link dietary data from a sample of 55,504 vegans, vegetarians, fish-eaters and meat-eaters with food-level data on greenhouse gas emissions, land use, water use, eutrophication risk and potential biodiversity loss from a review of 570 life-cycle assessments covering more than 38,000 farms in 119 countries. Our results include the variation in food production and sourcing that is observed in the review of life-cycle assessments. All environmental indicators showed a positive association with amounts of animal-based food consumed. Dietary impacts of vegans were 25.1% (95% uncertainty interval, 15.1-37.0%) of high meat-eaters (≥100 g total meat consumed per day) for greenhouse gas emissions, 25.1% (7.1-44.5%) for land use, 46.4% (21.0-81.0%) for water use, 27.0% (19.4-40.4%) for eutrophication and 34.3% (12.0-65.3%) for biodiversity. At least 30% differences were found between low and high meat-eaters for most indicators. Despite substantial variation due to where and how food is produced, the relationship between environmental impact and animal-based food consumption is clear and should prompt the reduction of the latter.

New Food Frequency Questionnaire to Estimate Vitamin K Intake in a Mediterranean Population

Vitamin K is a multifunctional micronutrient essential for human health, and deficiency has been linked to multiple pathological conditions. In this study, we aimed to develop and validate a new food frequency questionnaire (FFQ) to estimate total vitamin K intake, over the course of a 30-day interval, in a Portuguese, Mediterranean-based, population. We conducted a prospective study in a non-random sample of 38 healthy adult volunteers. The FFQ was designed based on a validated Portuguese FFQ used in nationally representative studies and on literature reviews, to include foods containing ≥5 μg of vitamin K/100 g and foods with a lower vitamin K content, yet commonly included in a Mediterranean diet. Vitamin K intake was estimated from 24 h recalls and six days of food records. The final FFQ included 54 food items which, according to regression analyses, explains 90% of vitamin K intake. Mean differences in vitamin K intake based on food records (80 ± 47.7 μg/day) and on FFQ (96.5 ± 64.3 μg/day) were statistically non-significant. Further, we found a strong correlation between both methods (r = 0.7; p = 0.003). Our results suggest that our new FFQ is a valid instrument to assess the last 30 days of vitamin K intake in the Portuguese Mediterranean population.

Longitudinal dietary trajectories from pregnancy to 3 years post delivery in women with obesity: relationships with adiposity

OBJECTIVE

The study aim was to examine the relationships between longitudinal dietary trajectories from early pregnancy to 3 years post delivery and adiposity measures in women with obesity.

METHODS

The diets of 1208 women with obesity in the UPBEAT (UK Pregnancy Better Eating and Activity Trial) study were assessed using a food frequency questionnaire (FFQ) at 15+0 to 18+6 weeks' gestation (baseline), 27+0 to 28+6 weeks' gestation, and 34+0 to 36+0 weeks' gestation, as well as 6 months and 3 years post delivery. Using factor analysis of the baseline FFQ data, four dietary patterns were identified: fruit & vegetable, African/Caribbean, processed, and snacking. The baseline scoring system was applied to the FFQ data at the four subsequent time points. Group-based trajectory modeling was used to extract longitudinal dietary pattern trajectories. Using adjusted regression, associations between dietary trajectories and log-transformed/standardized adiposity measures (BMI and waist and mid-upper arm circumferences) at 3 years post delivery were examined.

RESULTS

Two trajectories were found to best describe the data for the four individual dietary patterns; these were characterized as high and low adherence. A high adherence to the processed pattern was associated with a higher BMI (β = 0.38 [95% CI: 0.06-0.69]) and higher waist (β = 0.35 [0.03-0.67]) and mid-upper arm circumferences (β = 0.36 [0.04-0.67]) at 3 years post delivery.

CONCLUSIONS

In women with obesity, a processed dietary pattern across pregnancy and 3 years post delivery is associated with higher adiposity.

Associations between maternal dietary scores during early pregnancy with placental outcomes

Background and aims

Individual macronutrient and micronutrient effects on placental growth have been widely investigated. However, the influence of overall maternal diet is relatively unknown. Therefore, the aim of this study is to examine associations between a range of maternal dietary scores during early pregnancy with placental outcomes, and to investigate whether there is evidence of sexual dimorphism.

Methods

This analysis of the Lifeways Cross-Generational Cohort includes 276 mother-child pairs. A validated 148-item semi-quantitative food frequency questionnaire assessed maternal diet in early pregnancy. Dietary scores reflecting dietary quality [Healthy Eating Index (HEI-2015), Dietary Approaches to Stop Hypertension (DASH)], dietary inflammatory potential [Dietary Inflammatory Index (DII) and the energy adjusted DII (E-DII)], dietary antioxidant status [Dietary Antioxidant Quality (DAQ)], and glycemic and insulinemic loads/indices (GL/GI, IL/II) were calculated. Linear regression analyses assessed maternal dietary score relationships with untrimmed placental weight (PW) and birth weight:placental weight (BW:PW) ratio.

Results

In fully adjusted models, maternal E-DII and GI were positively associated, and HEI-2015 and DAQ were negatively associated with PW (B: 12.31, 95% CI: 0.41, 24.20, p = 0.04, B: 4.13, 95% CI: 0.10, 8.17, p = 0.04, B: -2.70, 95% CI: -5.03, -0.35, p = 0.02 and B: -15.03, 95% CI: -28.08, -1.98, p = 0.02, for E-DII, GI, HEI-2015 and DAQ respectively). Maternal DAQ associations with BW:PW ratio were attenuated. When stratified by sex, maternal GI and pregnancy-specific DAQ were associated with PW in female offspring (B: 5.61, 95% CI: 0.27, 10.96, p = 0.04 and B: -15.31, 95% CI: -30.35, -0.27, p = 0.046). Maternal E-DII and HEI-2015 were associated with PW in males (B: 24.31, 95% CI: 5.66, 42.96, p = 0.01 and B: -3.85, 95% CI: -7.47, -0.35, p = 0.03 respectively).

Conclusion

The results of this novel investigation suggest that maternal diet may influence placental development. Female fetuses may be more sensitive to increased glucose levels whereas male fetuses may be more susceptible to in-utero stresses that are regulated by inflammatory pathways and overall diet quality. Hence, early pregnancy offers an opportune time for a mother to prioritize dietary changes that focus on reducing inflammatory and glycemic responses.

Comparison between dietary assessment methods and biomarkers in estimating dietary (poly)phenol intake

Background: although widely used, there is limited understanding of the suitability of different dietary assessment tools to estimate (poly)phenol intake. This study aims to compare the agreement between a food frequency questionnaire (FFQ) and a 7-day food diary (7DD) in assessing (poly)phenol intake and explore their associations with the urinary and plasma (poly)phenol metabolites. Methods: healthy free-living participants aged 18-80 years (n = 413) completed a 7DD and an FFQ (EPIC-Norfolk) and provided a 24 h urine and a fasting plasma sample. A comprehensive in-house (poly)phenol database was used to estimate (poly)phenol intake. The phenolic metabolite levels were analysed using a validated LC-MS method. The agreement between dietary assessment methods and biomarkers were evaluated by intraclass correlation coefficients (ICC), weighted kappa, quartile classification, Bland-Altman plots and correlations. Results: the total (poly)phenol intake estimated from FFQ was higher than from 7DD (median 1463 and 1042 mg d^-1, respectively). The agreement between FFQ and 7DD were moderate (ICC 0.51-0.59) for total (poly)phenols, flavan-3-ols, total phenolic acids, hydroxycinnamic acids and alkylmethoxyphenols, and were poor for all the other classes and subclasses (ICC 0.00-0.48). Positive correlations with total urine phenolic metabolites were found in FFQ estimated anthocyanins, dihydroflavonols, total lignans, tyrosols, alkylmethoxyphenols, total phenolic acids, and total stilbenes and the 7DD estimated theaflavins and thearubigins (all FDR adjusted p values < 0.1). No significant correlations were found between total plasma phenolic metabolites and (poly)phenol intake. Conclusion: agreements between dietary assessment tools were moderate for the major classes of (poly)phenols, while agreements between (poly)phenol intake and biomarkers were poor. Future research using biomarker approaches to increase the accuracy of estimating (poly)phenol exposure in larger populations is needed.

Dietary Polyphenols in Relation to Gut Microbiota Composition in Saudi Arabian Females

Polyphenols may modulate gut microbiota; however, limited studies have examined this relationship relative to obesity. We aim to investigate the association between polyphenol intake and gut microbiota composition in relation to obesity indices among Saudi Arabian females. This study included 92 adults stratified by body mass index (BMI) into controls (BMI ≥ 18.5−24.9 kg/m2; n = 48) and cases (BMI ≥ 30.0 kg/m2; n = 44), and further divided into high and low polyphenol intake by median intake (252 mg/1000 kcal/day). Fecal samples were collected to analyze the gut microbiota composition via the whole-genome shotgun sequencing technique. Results showed that Flavonifractor plautii and Clostridium bolteae were positively correlated with polyphenol intake in the total sample (r = 0.22, p = 0.03; r = 0.28, p = 0.01, respectively). There were inverse correlations between Blautia wexlerae and polyphenol intake (r = −0.56, p < 0.01) in the case group, and between Bacteroides thetaiotaomicron and polyphenol intake (r = −0.45, p = 0.03) in the control group. Those in the case group with low polyphenol intake, and those with high waist-to-hip ratio (WHR; ≥0.83), showed significantly lower alpha-diversity than those in the control group with normal WHR (<0.83), (p < 0.05). Findings suggest that polyphenols are correlated with specific bacteria and may play an important role in the modulation of gut microbiota and obesity management.

Mixed Tree Nuts, Cognition, and Gut Microbiota: A 4-Week, Placebo-Controlled, Randomized Crossover Trial in Healthy Nonelderly Adults

BACKGROUND

Beneficial effects of nut supplementation on cognitive function have previously been demonstrated in young and older adults. Alterations to gut microbiota have also been shown following tree nut consumption. However, no data exists on the effects of nuts on cognition and intestinal microbial communities assessed within the same study.

OBJECTIVES

The study aimed to examine the effects of daily consumption of tree nuts for 4 wk on cognitive function (primary outcome), mood, metabolomics, and gut microbial species (secondary outcomes) in healthy, nonelderly adults.

METHODS

This randomized, placebo-controlled, double-blind, counterbalanced crossover study assessed the effects of 4 wk of supplementation with 30 g/d mixed tree nuts versus placebo on cognition and mood in 79 healthy adults aged 18-49 y. Metabolic responses, gut bacterial community structure, and the potential for these to impact cognition were explored using a multi-omic approach. Bacterial community analysis was conducted in Quantitative Insights Into Microbial Ecology 2 (QIIME2).

RESULTS

Mixed model analysis indicated that nut consumption led to significant improvements to accuracy (placebo M = 92.2% compared with NUTS M = 94.5%; P = 0.019) and speed of response (placebo M = 788 ms compared with NUTS M = 757 ms; P = 0.004) on a picture recognition task. No significant changes to bacterial community α or β diversity were observed when comparing nut consumption to the placebo arm. However, an unclassified Lachnospiraceae amplicon sequence variant (ASV) was significantly enriched in participants when supplemented with nuts (P = 0.015). No correlations were observed between the changes to picture recognition and the changes to the unclassified Lachnospiraceae ASV. There were no significant changes to the urinary metabolome.

CONCLUSIONS

These findings indicate a positive effect of nut on cognition following only 4 wk of consumption in a healthy nonelderly sample, as well as upregulation of a microbial taxa associated with gut health. The effects appear to be independent of one another, but further exploration is required in those experiencing cognitive decline and/or gut dysbiosis.

Machine learning integration of multimodal data identifies key features of blood pressure regulation

BACKGROUND

Association studies have identified several biomarkers for blood pressure and hypertension, but a thorough understanding of their mutual dependencies is lacking. By integrating two different high-throughput datasets, biochemical and dietary data, we aim to understand the multifactorial contributors of blood pressure (BP).

METHODS

We included 4,863 participants from TwinsUK with concurrent BP, metabolomics, genomics, biochemical measures, and dietary data. We used 5-fold cross-validation with the machine learning XGBoost algorithm to identify features of importance in context of one another in TwinsUK (80% training, 20% test). The features tested in TwinsUK were then probed using the same algorithm in an independent dataset of 2,807 individuals from the Qatari Biobank (QBB).

FINDINGS

Our model explained 39·2% [4·5%, MAE:11·32 mmHg (95%CI, +/- 0·65)] of the variance in systolic BP (SBP) in TwinsUK. Of the top 50 features, the most influential non-demographic variables were dihomo-linolenate, cis-4-decenoyl carnitine, lactate, chloride, urate, and creatinine along with dietary intakes of total, trans and saturated fat. We also highlight the incremental value of each included dimension. Furthermore, we replicated our model in the QBB [SBP variance explained = 45·2% (13·39%)] cohort and 30 of the top 50 features overlapped between cohorts.

INTERPRETATION

We show that an integrated analysis of omics, biochemical and dietary data improves our understanding of their in-between relationships and expands the range of potential biomarkers for blood pressure. Our results point to potentially key biological pathways to be prioritised for mechanistic studies.

FUNDING

Chronic Disease Research Foundation, Medical Research Council, Wellcome Trust, Qatar Foundation.

Testing the protein-leverage hypothesis using population surveillance data

It is hypothesized that humans exhibit 'protein leverage' (PL), whereby regulation of absolute protein intake results in the over-consumption of non-protein food on low percentage protein diets. Testing for PL using dietary surveillance data involves seeking evidence for a negative association between total energy intake and percentage energy from protein. However, it is unclear whether such an association might emerge without PL due to the structure of intake data (protein and non-protein intakes have different means and variances and covary). We derive a set of models that describe the association between the expected estimate of PL and the distributions of protein and non-protein intake. Models were validated via simulation. Patterns consistent with PL will not emerge simply because protein intake has a lower mean and/or variance than non-protein. Rather, evidence of PL is observed where protein has a lower index of dispersion (variance/mean) than non-protein intake. Reciprocally, the stronger PL is the lower the index of dispersion for protein intake becomes. Disentangling causality is ultimately beyond the power of observational data alone. However, we show that one can correct for confounders (e.g. age) in generating signals of PL, and describe independent measures that can anchor inferences around the role of PL.

The association between Mediterranean diet adherence and allostatic load in older adults

Allostatic load (AL) is a multisystemic index of biological wear and tear which is associated with poor health outcomes. In recent years, researchers have examined the association between dietary pattern intake and AL; however, no studies to date have examined the relationship between AL and consumption of a Mediterranean diet. Blood and urine samples were collected from 201 community-dwelling older adults who completed a Food Frequency Questionnaire (FFQ). A Mediterranean Diet Score (MDS) was calculated based on previous recommendations and a sex-based AL index was calculated using a count-based approach for 16 biomarkers associated with neuroendocrine, immune, cardiovascular, or metabolic function. It was hypothesized that a higher MDS would be associated with lower AL, and that this association would be particularly robust for the immune and metabolic subcomponents of the AL index. In support of the primary study hypotheses, generalized linear models revealed a significant inverse relationship between MDS and AL (ß = -0.03, P = 0.037). However, subcomponents of the AL model were not significantly associated with MDS. Exploratory sub-group analyses by sex suggested that the association between AL and MDS was more robust in male than in female participants. The current findings are interpreted with caution given the study design and sample characteristics. Nonetheless, these findings contribute to the literature supporting the Mediterranean diet as an important lifestyle behavior that may minimize AL, and therefore support healthy aging.

Estimating national and subnational nutrient intake distributions of global diets

BACKGROUND

Access to high-quality dietary intake data is central to many nutrition, epidemiology, economic, environmental, and policy applications. When data on individual nutrient intakes are available, they have not been consistently disaggregated by sex and age groups, and their parameters and full distributions are often not publicly available.

OBJECTIVES

We sought to derive usual intake distributions for as many nutrients and population subgroups as possible, use these distributions to estimate nutrient intake inadequacy, compare these distributions and evaluate the implications of their shapes on the estimation of inadequacy, and make these distributions publicly available.

METHODS

We compiled dietary data sets from 31 geographically diverse countries, modeled usual intake distributions for 32 micronutrients and 21 macronutrients, and disaggregated these distributions by sex and age groups. We compared the variability and skewness of the distributions and evaluated their similarity across countries, sex, and age groups. We estimated intake inadequacy for 16 nutrients based on a harmonized set of nutrient requirements and bioavailability estimates. Last, we created an R package-nutriR-to make these distributions freely available for users to apply in their own analyses.

RESULTS

Usual intake distributions were rarely symmetric and differed widely in variability and skewness across nutrients and countries. Vitamin intake distributions were more variable and skewed and exhibited less similarity among countries than other nutrients. Inadequate intakes were high and geographically concentrated, as well as generally higher for females than males. We found that the shape of usual intake distributions strongly affects estimates of the prevalence of inadequate intakes.

CONCLUSIONS

The shape of nutrient intake distributions differs based on nutrient and subgroup and strongly influences estimates of nutrient intake inadequacy. This research represents an important contribution to the availability and application of dietary intake data for diverse subpopulations around the world.

Adipose methylome integrative-omic analyses reveal genetic and dietary metabolic health drivers and insulin resistance classifiers

BACKGROUND

There is considerable evidence for the importance of the DNA methylome in metabolic health, for example, a robust methylation signature has been associated with body mass index (BMI). However, visceral fat (VF) mass accumulation is a greater risk factor for metabolic disease than BMI alone. In this study, we dissect the subcutaneous adipose tissue (SAT) methylome signature relevant to metabolic health by focusing on VF as the major risk factor of metabolic disease. We integrate results with genetic, blood methylation, SAT gene expression, blood metabolomic, dietary intake and metabolic phenotype data to assess and quantify genetic and environmental drivers of the identified signals, as well as their potential functional roles.

METHODS

Epigenome-wide association analyses were carried out to determine visceral fat mass-associated differentially methylated positions (VF-DMPs) in SAT samples from 538 TwinsUK participants. Validation and replication were performed in 333 individuals from 3 independent cohorts. To assess functional impacts of the VF-DMPs, the association between VF and gene expression was determined at the genes annotated to the VF-DMPs and an association analysis was carried out to determine whether methylation at the VF-DMPs is associated with gene expression. Further epigenetic analyses were carried out to compare methylation levels at the VF-DMPs as the response variables and a range of different metabolic health phenotypes including android:gynoid fat ratio (AGR), lipids, blood metabolomic profiles, insulin resistance, T2D and dietary intake variables. The results from all analyses were integrated to identify signals that exhibit altered SAT function and have strong relevance to metabolic health.

RESULTS

We identified 1181 CpG positions in 788 genes to be differentially methylated with VF (VF-DMPs) with significant enrichment in the insulin signalling pathway. Follow-up cross-omic analysis of VF-DMPs integrating genetics, gene expression, metabolomics, diet, and metabolic traits highlighted VF-DMPs located in 9 genes with strong relevance to metabolic disease mechanisms, with replication of signals in FASN, SREBF1, TAGLN2, PC and CFAP410. PC methylation showed evidence for mediating effects of diet on VF. FASN DNA methylation exhibited putative causal effects on VF that were also strongly associated with insulin resistance and methylation levels in FASN better classified insulin resistance (AUC=0.91) than BMI or VF alone.

CONCLUSIONS

Our findings help characterise the adiposity-associated methylation signature of SAT, with insights for metabolic disease risk.

Nutritional Biomarkers and Factors Correlated with Poor Sleep Status among Young Females: A Case-Control Study

Poor sleep status is associated with several health problems. Nutritional biomarkers and factors related to poor sleep are understudied. This study aimed to identify nutrition biomarkers and factors related to sleep status in healthy young Saudi females. The study included 92 normal-weight and obese Saudi females aged 19−25. Fasting blood glucose, insulin, and lipid profiles were measured. Insulin resistance was calculated on the basis of the homeostasis model assessment of insulin resistance (HOMA-IR) method. Anthropometric, stress, physical activity, and dietary data were collected. Data on the polyphenol content in foods were retrieved from the Phenol-Explorer database. The sleep status was assessed using the Pittsburgh sleep quality index (PSQI). Associations between variables were assessed using the multiple logistic regression model. Around 76% of the participants had poor sleep status (PSQI > 5). Multiple logistic regression reported high polyphenol intake as a protective factor against poor sleep (OR 0.24; 95% CI 0.07−0.83; p = 0.03) and HOMA-IR as an independent risk for poor sleep (OR 4.97; 95% CI 1.11−22.31; p = 0.04). Other nutritional biomarkers and factors, such as BMI, lipid profile, and vitamins, revealed a trend but were not significant. In conclusion, poor sleep status is associated with insulin resistance and low polyphenol intake among women of reproductive age.

Assessing Adherence to Healthy Dietary Habits Through the Urinary Food Metabolome: Results From a European Two-Center Study

Background

Diet is one of the most important modifiable lifestyle factors in human health and in chronic disease prevention. Thus, accurate dietary assessment is essential for reliably evaluating adherence to healthy habits.

Objectives

The aim of this study was to identify urinary metabolites that could serve as robust biomarkers of diet quality, as assessed through the Alternative Healthy Eating Index (AHEI-2010).

Design

We set up two-center samples of 160 healthy volunteers, aged between 25 and 50, living as a couple or family, with repeated urine sampling and dietary assessment at baseline, and 6 and 12 months over a year. Urine samples were subjected to large-scale metabolomics analysis for comprehensive quantitative characterization of the food-related metabolome. Then, lasso regularized regression analysis and limma univariate analysis were applied to identify those metabolites associated with the AHEI-2010, and to investigate the reproducibility of these associations over time.

Results

Several polyphenol microbial metabolites were found to be positively associated with the AHEI-2010 score; urinary enterolactone glucuronide showed a reproducible association at the three study time points [false discovery rate (FDR): 0.016, 0.014, 0.016]. Furthermore, other associations were found between the AHEI-2010 and various metabolites related to the intake of coffee, red meat and fish, whereas other polyphenol phase II metabolites were associated with higher AHEI-2010 scores at one of the three time points investigated (FDR < 0.05 or β ≠ 0).

Conclusion

We have demonstrated that urinary metabolites, and particularly microbiota-derived metabolites, could serve as reliable indicators of adherence to healthy dietary habits.

Clinical Trail Registration

www.ClinicalTrials.gov, Identifier: NCT03169088.

Examining the cognitive benefits of probiotic supplementation in physically active older adults: A randomized clinical trial

The prevalence of dementia is projected to increase with the growing older adult population and prevention strategies are urgently needed. Two promising interventions include physical activity (PA) and probiotic supplementation, with initial findings suggesting their combined use may confer greater cognitive benefits than either intervention alone. However, no study has yet examined the effects of probiotic supplementation on cognitive function in healthy, physically active older adults. The present study used archival data from a randomized clinical trial including 127 physically active, middle-aged to older adults (avg age 64.3 years) with self-reported PA levels meeting or exceeding recommendations to investigate the effects of probiotic supplementation (Lactobacillus rhamnosus GG; L.GG) on cognitive outcomes. Repeated measures ANOVAs showed no significant changes in cognitive performance from baseline to follow up as an effect of L.GG consumption. These results suggest that probiotic supplementation may not improve cognitive function in persons already engaged in high levels of PA. Future research should include prospective studies to determine whether long-term use of probiotic supplementation may help prevent cognitive decline. Novelty: • Initial research shows promising cognitive benefits of combined physical activity and probiotics consumption. • L.GG did not lead to acute cognitive improvements for older adults already meeting physical activity guidelines. • Prospective studies examining prevention of cognitive decline with probiotics in healthy and clinical samples are much needed.

Measurement Error Affecting Web- and Paper-Based Dietary Assessment Instruments: Insights From the Multi-Cohort Eating and Activity Study for Understanding Reporting Error

Few biomarker-based validation studies have examined error in online self-report dietary assessment instruments, and food records (FRs) have been considered less than food frequency questionnaires (FFQs) and 24-hour recalls (24HRs). We investigated measurement error in online and paper-based FFQs, online 24HRs, and paper-based FRs in 3 samples drawn primarily from 3 cohorts, comprising 1,393 women and 1,455 men aged 45-86 years. Data collection occurred from January 2011 to October 2013. Attenuation factors and correlation coefficients between reported and true usual intake for energy, protein, sodium, potassium, and respective densities were estimated using recovery biomarkers. Across studies, average attenuation factors for energy were 0.07, 0.07, and 0.19 for a single FFQ, 24HR, and FR, respectively. Correlation coefficients for energy were 0.24, 0.23, and 0.40, respectively. Excluding energy, the average attenuation factors across nutrients and studies were 0.22 for a single FFQ, 0.22 for a single 24HR, and 0.51 for a single FR. Corresponding correlation coefficients were 0.31, 0.34, and 0.53, respectively. For densities (nutrient expressed relative to energy), the average attenuation factors across studies were 0.37, 0.17, and 0.50, respectively. The findings support prior research suggesting different instruments have unique strengths that should be leveraged in epidemiologic research.

Empowering consumers to PREVENT diet-related diseases through OMICS sciences (PREVENTOMICS): protocol for a parallel double-blinded randomised intervention trial to investigate biomarker-based nutrition plans for weight loss

INTRODUCTION

Personalised nutrition holds immense potential over conventional one-size-fits-all approaches for preventing and treating diet-related diseases, such as obesity. The current study aims to examine whether a personalised nutritional plan produces more favourable health outcomes than a standard approach based on general dietary recommendations in subjects with overweight or obesity and elevated waist circumference.

METHODS AND ANALYSIS

This project is a 10-week parallel, double-blinded randomised intervention trial. We plan to include 100 adults aged 18-65 years interested in losing weight, with body mass index ≥27 but<40 kg/m² and elevated waist circumference (males >94 cm; females >80 cm). Participants will be categorised into one of five predefined 'clusters' based on their individual metabolic biomarker profile and genetic background, and will be randomised in a 1:1 ratio to one of two groups: (1) personalised plan group that will receive cluster-specific meals every day for 6 days a week, in conjunction with a personalised behavioural change programme via electronic push notifications; or (2) control group that will receive meals following the general dietary recommendations in conjunction with generic health behaviour prompts. The primary outcome is the difference between groups (personalised vs control) in the change in fat mass from baseline. Secondary outcomes include changes in weight and body composition, fasting blood glucose and insulin, lipid profile, adipokines, inflammatory biomarkers, and blood pressure. Other outcomes involve measures of physical activity and sleep patterns, health-related quality of life, dietary intake, eating behaviour, and biomarkers of food intake. The effect of the intervention on the primary outcome will be analysed by means of linear mixed models.

ETHICS AND DISSEMINATION

The protocol has been approved by the Ethics Committee of the Capital Region, Copenhagen, Denmark. Study findings will be disseminated through peer-reviewed publications, conference presentations and media outlets.

TRIAL REGISTRATION NUMBER

NCT04590989.

Towards targeted dietary support for shift workers with type 2 diabetes (Shift-Diabetes study): A mixed-methods case study protocol

BACKGROUND

Blood glucose is higher in people working night shifts compared to day workers. Changes to eating behaviour, activity and sleep patterns in addition to circadian disruption are likely to impact glucose management in night-shift workers with type 2 diabetes.

AIM

To investigate current dietary intake and glucose variability during night work, including barriers and facilitators to dietary behaviour in this context.

METHODS

A mixed-methods case study will be conducted. Shift workers with type 2 diabetes working in a hospital setting will be recruited to this two-part study. Part 1: 70 participants will complete a 10-day observational study collecting data on continuous glucose, diet (self-report diary), sleep and physical activity during a period covering night work, rest days and non-night workdays. Mean glucose concentration and variability, and the mean healthy diet index score, will be compared between days of night work, non-night work and rest, after adjusting for other individual factors (sleep/physical activity/demographics). Part 2: A sample (n~13) will complete semi-structured interviews based on behavioural science frameworks to explore barriers/enablers to dietary behaviour when working night shifts. This will inform a quantitative survey to explore the generalisability of interview findings.

DISCUSSION

Findings from Part 1 and 2 will be triangulated to identify potential intervention strategies to address key barriers and enablers to healthier eating, and in turn improved glucose control, in shift workers with type 2 diabetes. This will be facilitated through stakeholder consultation and application of behavioural science frameworks. Shift-Diabetes study registration: ISRCTN11764942.

Cross-cohort gut microbiome associations with immune checkpoint inhibitor response in advanced melanoma

The composition of the gut microbiome has been associated with clinical responses to immune checkpoint inhibitor (ICI) treatment, but there is limited consensus on the specific microbiome characteristics linked to the clinical benefits of ICIs. We performed shotgun metagenomic sequencing of stool samples collected before ICI initiation from five observational cohorts recruiting ICI-naive patients with advanced cutaneous melanoma (n = 165). Integrating the dataset with 147 metagenomic samples from previously published studies, we found that the gut microbiome has a relevant, but cohort-dependent, association with the response to ICIs. A machine learning analysis confirmed the link between the microbiome and overall response rates (ORRs) and progression-free survival (PFS) with ICIs but also revealed limited reproducibility of microbiome-based signatures across cohorts. Accordingly, a panel of species, including Bifidobacterium pseudocatenulatum, Roseburia spp. and Akkermansia muciniphila, associated with responders was identified, but no single species could be regarded as a fully consistent biomarker across studies. Overall, the role of the human gut microbiome in ICI response appears more complex than previously thought, extending beyond differing microbial species simply present or absent in responders and nonresponders. Future studies should adopt larger sample sizes and take into account the complex interplay of clinical factors with the gut microbiome over the treatment course.

Associations between a protective lifestyle behaviour score and biomarkers of chronic low-grade inflammation: a cross-sectional analysis in middle-to-older aged adults

BACKGROUND/OBJECTIVES

Certain lifestyle behaviours may have a protective effect against low-grade systemic inflammation, which is linked to chronic disease. Our objective was to examine associations between a five-component protective lifestyle behaviour (PLB) score and a range of pro-inflammatory cytokines, adipocytokines, acute-phase response proteins, coagulation factors and white blood cells.

SUBJECTS/METHODS

This was a cross-sectional study of 2045 middle-to-older aged men and women. Low-risk behaviours included never smoking, moderate alcohol intake, moderate-to-vigorous physical activity, a high-quality diet (upper 40% Dietary Approaches to Stop Hypertension score) and a normal body mass index (BMI) (18.5-24.9 kg/m²). Linear and logistic regression analyses tested individual protective behaviour and PLB score associations with biomarkers.

RESULTS

Analysis of individual low-risk behaviours revealed varied associations depending on the biomarker, with normal BMI showing the most consistent associations. Examination of the PLB score showed that compared to subjects with 4-5 protective behaviours, those with 0-1 protective behaviours had 1.4-3.8 increased odds of having a less favourable inflammatory profile. Following adjustment for BMI, significant trend relationships were observed between the number of protective behaviours and complement component 3 (P < 0.001), c-reactive protein (P < 0.001), interleukin 6 (P < 0.001), tumour necrosis factor alpha (P < 0.001) and white blood cell count (P < 0.001) concentrations.

CONCLUSIONS

These results suggest a cumulative protective effect of healthy lifestyle behaviours against systemic inflammation in middle-to-older aged adults which is independent of having a healthy body weight.

Characterisation, procedures and heritability of acute dietary intake in the Twins UK cohort: an observational study

BACKGROUND

Estimated food records (EFR) are a common dietary assessment method. This investigation aimed to; (1) define the reporting quality of the EFR, (2) characterise acute dietary intake and eating behaviours, (3) describe diet heritability.

METHODS

A total of 1974 one-day EFR were collected from 1858 participants in the TwinsUK cohort between 2012 and 2017. EFR were assessed using a six-point scoring system to determine reporting quality. The frequency and co-occurrence of food items was examined using word clouds and co-occurrence networks. The impact of eating behaviours on weight, BMI and nutrient intake were explored using mixed-effect linear regression models. Finally, diet heritability was estimated using ACE modelling.

RESULTS

We observed that 75% of EFR are of acceptable reporting quality (score > 5). Black tea and semi-skimmed milk were the most consumed items, on an individual basis (respectively 8.27, 6.25%) and paired (0.21%) as co-occurring items. Breakfast consumption had a significantly (p = 5.99 × 10- 7) greater impact on energy (kcal) (mean 1874.67 (±SD 532.42)) than skipping breakfast (1700.45 (±SD 620.98)), however only length of eating window was significantly associated with body weight (kg) (effect size 0.21 (±SD 0.10), p = 0.05) and BMI (effect size 0.08 (±SD 0.04), p = 0.04) after adjustment for relevant covariates. Lastly, we reported that both length of eating window (h2 = 33%, CI 0.24; 0.41), and breakfast consumption (h2 = 11%, CI 0.02; 0.21) were weakly heritable.

CONCLUSIONS

EFR describing acute dietary intake allow for eating behaviour characterisation and can supplement habitual diet intake assessments. Novel findings of heritability warrant further investigation.