Empowering healthcare professionals in West Africa-A feasibility study and qualitative assessment of a dietary screening tool to identify adults at high risk of hypertension

Dietary risks significantly contribute to hypertension in West Africa. Food frequency questionnaires (FFQs) can provide valuable dietary assessment but require rigorous validation and careful design to facilitate usability. This study assessed the feasibility and interest of a dietary screening tool for identifying adults at high risk of hypertension in Nigeria. Fifty-eight (58) consenting adult patients with hypertension and their caregivers and 35 healthcare professionals from a single-centre Nigerian hospital were recruited to complete a 27-item FFQ at two-time points and three 24-hour recalls for comparison in a mixed method study employing both quantitative questionnaires and qualitative techniques to elicit free form text. Data analyses were conducted using R software version 4.3.1 and NVivo version 14. The trial was registered with ClinicalTrials.gov: NCT05973760. The mean age of patients was 42.6 ± 11.9 years, with an average SBP of 140.3 ± 29.8 mmHg and a BMI of 29.5 ± 7.1 Kg/m2. The adherence rate was 87.9%, and the mean completion time was 7:37 minutes. 96.6% of patients found the FFQ easy to complete, comprehensive, and valuable. A minority reported difficulty (3.4%), discomfort (10.3%), and proposed additional foods (6.9%). Healthcare professionals considered the dietary screening tool very important (82.9%) and expressed a willingness to adopt the tool, with some suggestions for clarification. Patients and healthcare professionals found the screening tool favourable for dietary counselling in hypertension care. The tailored dietary screening tool (FFQ) demonstrated promising feasibility for integration into clinical care as assessed by patients and healthcare professionals. Successful implementation may benefit from proactive time management and addressing training needs. This user-centred approach provided key insights to refine FFQ and set the foundation for ongoing validity testing and evaluation in clinical practice.

Dietary assessment and prevention of hypertension in Nigeria: Protocol for a retrospective cross-sectional study for the development and validation of a food frequency questionnaire for clinical use

Contrary to North America and Europe, the prevalence of hypertension is rising in West Africa. With a transition from whole foods to processed foods in Nigeria, diet plays a key driver of hypertension. To combat this, the national nutritional guidelines in Nigeria were implemented, but their translation into actionable tools for clinicians remains a challenge. Currently, there are no simple dietary assessment tools that are concise and suitable to be incorporated into clinical care without requiring extensive data analysis while still providing personalised dietary support to their patients. This study aims to deliver a clinically tested and validated short dietary assessment tool for clinicians, patients, and researchers across Nigeria to provide personalised dietary advice for patients with hypertension. The study will be conducted in two phases: Phase 1 (n = 75) will investigate the feasibility of the short FFQ and its agreement with 24-hour dietary recalls (3x) in a clinical setting in Nigeria. During the analysis of Phase 1 data, a scoring system will be developed based on the associations between individual food items in the FFQ and measures of hypertension. Phase 2 (n = 50) will assess the acceptability of the FFQ and validate the association between the FFQ score and hypertension. Expected outcomes: The development of a clinically tested and validated short food frequency questionnaire that will be ready to use by clinicians, patients, and researchers across Nigeria to support the prevention and management of hypertension. This study will contribute to knowledge on dietary assessment and hypertension prevention by developing a validated and acceptable FFQ, which will be valuable for clinicians and researchers for personalised dietary recommendations to combat hypertension in Nigeria.

Overnutrition is a risk factor for iron, but not for zinc or vitamin A deficiency in children and young people: a systematic review and meta-analysis

INTRODUCTION

Traditionally associated with undernutrition, increasing evidence suggests micronutrient deficiencies can coexist with overnutrition. Therefore, this work aimed to systematically review the associations between iron, zinc and vitamin A (VA) status and weight status (both underweight and overweight) in children and young people.

METHODS

Ovid Medline, Ovid Embase, Scopus and Cochrane databases were systematically searched for observational studies assessing micronutrient status (blood, serum or plasma levels of iron, zinc or VA biomarkers) and weight status (body mass index or other anthropometric measurement) in humans under 25 years of any ethnicity and gender. Risk of bias assessment was conducted using the American Dietetic Association Quality Criteria Checklist. Where possible, random effects restricted maximum likelihood meta-analyses were performed.

RESULTS

After screening, 83 observational studies involving 190 443 participants from 44 countries were identified, with many studies having reported on more than one micronutrient and/or weight status indicator. Iron was the most investigated micronutrient, with 46, 28 and 27 studies reporting data for iron, zinc and VA status, respectively. Synthesising 16 records of OR from seven eligible studies, overnutrition (overweight and obesity) increased odds of iron deficiency (ID) (OR (95% CI): 1.51 (1.20 to 1.82), p<0.0001, I2=40.7%). Odds appeared to be higher for children living with obesity (1.88 (1.33 to 2.43), p<0.0001, I2=20.6%) in comparison to those with overweight (1.31 (0.98 to 1.64), p<0.0001, I2=40.5%), although between group differences were not significant (p=0.08).

CONCLUSIONS

Overnutrition is associated with increased risk of ID, but not zinc or VA deficiencies, with an inverted U-shaped relationship observed between iron status and bodyweight. Our results highlight significant heterogeneity in the reporting of micronutrient biomarkers and how deficiencies were defined. Inflammation status was rarely adequately accounted for, and the burden of ID may well be under-recognised, particularly in children and young people living with overnutrition.

PROSPERO REGISTRATION NUMBER

CRD42020221523.

Phytosterol and phytostanol-mediated epigenetic changes in cancer and other non-communicable diseases: a systematic review

Phytosterols/phytostanols are bioactive compounds found in vegetable oils, nuts and seeds and added to a range of commercial food products. Consumption of phytosterols/phytostanols reduces levels of circulating LDL-cholesterol, a causative biomarker of CVD, and is linked to a reduced risk of some cancers. Individuals who consume phytosterols/phytostanols in their diet may do so for many years as part of a non-pharmacological route to lower cholesterol or as part of a healthy diet. However, the impact of long term or high intakes of dietary phytosterols/phytostanols has not been on whole-body epigenetic changes before. The aim of this systematic review was to identify all publications that have evaluated changes to epigenetic mechanisms (post-translation modification of histones, DNA methylation and miRNA expression) in response to phytosterols/phytostanols. A systematic search was performed that returned 226 records, of which eleven were eligible for full-text analysis. Multiple phytosterols were found to inhibit expression of histone deacetylase (HDAC) enzymes and were also predicted to directly bind and impair HDAC activity. Phytosterols were found to inhibit the expression and activity of DNA methyl transferase enzyme 1 and reverse cancer-associated gene silencing. Finally, phytosterols have been shown to regulate over 200 miRNA, although only five of these were reported in multiple publications. Five tissue types (breast, prostate, macrophage, aortic epithelia and lung) were represented across the studies, and although phytosterols/phytostanols alter the molecular mechanisms of epigenetic inheritance in these mammalian cells, studies exploring meiotic or transgenerational inheritance were not found.

Practical Lifestyle Management of Nonalcoholic Fatty Liver Disease for Busy Clinicians

Weight loss achieved through a combination of healthy eating patterns that encompass the principles of the Mediterranean diet and regular physical activity is the most evidence-based treatment for nonalcoholic fatty liver disease. Although other types of diets have demonstrated efficacy in liver fat reduction, the Mediterranean diet confers additional cardiometabolic benefits. Macronutrient composition, food choices, and timing of eating can be tailored to individual preferences, culture, and financial circumstances; however, recommended healthy eating patterns are characterized by minimally processed or unprocessed foods (vegetables, legumes, nuts and seeds, fruits, whole grains, and unprocessed meats and fish) that are low in sugar, refined carbohydrates, and saturated fat and high in fiber, polyphenols, vitamins, minerals, and healthy fats. Physical activity can independently improve steatosis, prevent fibrosis and cirrhosis, and reduce mortality.

Supermarket top-up of Healthy Start vouchers increases fruit and vegetable purchases in low-income households

Stark, widening health and income inequalities in the United Kingdom underpin the need for increased support for low-income families to access affordable and nutritious foods. Using anonymised supermarket loyalty card transaction records, this study aimed to assess how an additional Healthy Start voucher (HSV) top-up of £2, redeemable only against fruit and vegetables (FVs), was associated with FV purchases among at-risk households. Transaction and redemption records from 150 loyalty card-holding households, living in northern England, who had engaged with the top-up scheme, were analysed to assess the potential overall population impact. Using a pre-post study design, 133 of these households' records from 2021 were compared with equivalent time periods in 2019 and 2020. Records were linked to product, customer and store data, permitting comparisons using Wilcoxon matched-pairs sign-ranked tests and relationships assessed with Spearman's Rho. These analyses demonstrated that 0.9 more portions of FV per day per household were purchased during the scheme compared to the 2019 baseline (p = 0.0017). The percentage of FV weight within total baskets also increased by 1.6 percentage points (p = 0.0242), although the proportional spend on FV did not change. During the scheme period, FV purchased was higher by 0.4 percentage points (p = 0.0012) and 1.6 percentage points (p = 0.0062) according to spend and weight, respectively, in top-up redeeming baskets compared to non-top-up redeeming baskets with at least one FV item and was associated with 5.5 more HSV 'Suggested' FV portions (p < 0.0001). The median weight of FV purchased increased from 41.83 kg in 2019 to 54.14 kg in 2021 (p = 0.0017). However, top-up vouchers were only redeemed on 9.1% of occasions where FV were purchased. In summary, this study provides novel data showing that safeguarding funds exclusively for FV can help to increase access to FV in low-income households. These results yield important insights to inform public policy aimed at levelling up health inequalities.

Dietary factors and hypertension risk in West Africa: a systematic review and meta-analysis of observational studies

BACKGROUND

Contrary to North America and Europe, the prevalence of hypertension is rising in West Africa. Although diet is implicated as a contributor to this trend, nutritional guidelines in West Africa are not tailored to address this concern. This study aimed to address this limitation by investigating dietary factors common to West Africa and evaluating their association with hypertension.

METHODS

PubMed, Scopus, Web of Science, and Medline were searched to identify studies that investigated diet and hypertension in West African adults. All meta-analyses used a generic inverse-variance random effects model, with subgroup analyses by age, BMI, and study location, and were performed in R.

RESULTS

Three thousand, two hundred ninety-eight studies were identified, of which 31 ( n  = 48 809 participants) satisfied inclusion criteria - all cross-sectional. Meta-analyses of the association between dietary factors and hypertension included dietary fat [odds ratio (OR) = 1.76; 95% confidence interval (95% CI) 1.44-2.14; P  < 0.0001], red meat (OR = 1.51; 95% CI: 1.04-2.18; P  = 0.03), junk-food (OR = 1.41; 95% CI: 1.19-1.67; P  < 0.0001), dietary salt (OR = 1.25; 95% CI: 1.12-1.40; P  < 0.0001), alcohol (OR = 1.17; 95% CI: 1.03-1.32; P  = 0.013), and 'fruits and vegetables' (OR = 0.80; 95% CI: 0.24-1.17; P  < 0.0001). Subgroup analyses suggested that 'fruit and vegetable' consumption is less protective in the elderly.

CONCLUSION

High consumption of dietary salt, red meat, dietary fat, junk food, and alcohol are associated with increased odds of hypertension, whereas high fruit and vegetable appear protective. This region-specific evidence will support the development of nutritional assessment tools for clinicians, patients, and researchers aiming to reduce hypertension in West Africa.

Metabolic drivers of dysglycemia in pregnancy: ethnic-specific GWAS of 146 metabolites and 1-sample Mendelian randomization analyses in a UK multi-ethnic birth cohort

Introduction

Gestational diabetes mellitus (GDM) is the most common pregnancy complication worldwide and is associated with short- and long-term health implications for both mother and child. Prevalence of GDM varies between ethnicities, with South Asians (SAs) experiencing up to three times the risk compared to white Europeans (WEs). Recent evidence suggests that underlying metabolic difference contribute to this disparity, but an investigation of causality is required.

Methods

To address this, we paired metabolite and genomic data to evaluate the causal effect of 146 distinct metabolic characteristics on gestational dysglycemia in SAs and WEs. First, we performed 292 GWASs to identify ethnic-specific genetic variants associated with each metabolite (P ≤ 1 x 10-5) in the Born and Bradford cohort (3688 SA and 3354 WE women). Following this, a one-sample Mendelian Randomisation (MR) approach was applied for each metabolite against fasting glucose and 2-hr post glucose at 26-28 weeks gestation. Additional GWAS and MR on 22 composite measures of metabolite classes were also conducted.

Results

This study identified 15 novel genome-wide significant (GWS) SNPs associated with tyrosine in the FOXN and SLC13A2 genes and 1 novel GWS SNP (currently in no known gene) associated with acetate in SAs. Using MR approach, 14 metabolites were found to be associated with postprandial glucose in WEs, while in SAs a distinct panel of 11 metabolites were identified. Interestingly, in WEs, cholesterols were the dominant metabolite class driving with dysglycemia, while in SAs saturated fatty acids and total fatty acids were most commonly associated with dysglycemia.

Discussion

In summary, we confirm and demonstrate the presence of ethnic-specific causal relationships between metabolites and dysglycemia in mid-pregnancy in a UK population of SA and WE pregnant women. Future work will aim to investigate their biological mechanisms on dysglycemia and translating this work towards ethnically tailored GDM prevention strategies.

Non-Alcoholic Fatty Liver Disease and Vitamin D in the UK Biobank: A Two-Sample Bidirectional Mendelian Randomisation Study

Evidence for a role for vitamin D in non-alcoholic fatty liver disease (NAFLD) pathogenesis is conflicting. As Mendelian randomisation (MR) avoids many limitations of conventional observational studies, this two-sample bidirectional MR analysis was conducted to determine the following: (i) whether genetically predicted 25-hydroxyvitamin D [25(OH)D] levels are a risk factor for NAFLD, and (ii) whether genetic risk for NAFLD influences 25(OH)D levels. Single-nucleotide polymorphisms (SNPs) associated with serum 25(OH)D levels were obtained from the European ancestry-derived SUNLIGHT consortium. SNPs associated with NAFLD or NASH (p-value < 1 × 10−5) were extracted from previous studies and supplemented by genome-wide association studies (GWASs) performed in the UK Biobank. These GWASs were done both without (primary analysis) and with (sensitivity analysis) the population-level exclusion of other liver diseases (e.g., alcoholic liver diseases, toxic liver diseases, viral hepatitis, etc.). Subsequently, MR analyses were performed to obtain effect estimates using inverse variance weighted (IVW) random effect models. Cochran’s Q statistic, MR-Egger regression intercept, MR pleiotropy residual sum and outlier (MR-PRESSO) analyses were used to assess pleiotropy. No causal association of genetically predicted serum 25(OH)D (per standard deviation increase) with risk of NAFLD was identified in either the primary analysis: n = 2757 cases, n = 460,161 controls, odds ratio (95% confidence interval): 0.95 (0.76, −1.18), p = 0.614; or the sensitivity analysis. Reciprocally, no causal association was identified between the genetic risk of NAFLD and serum 25(OH)D levels, OR = 1.00 (0.99, 1.02, p = 0.665). In conclusion, this MR analysis found no evidence of an association between serum 25(OH)D levels and NAFLD in a large European cohort.

Ergothioneine: an underrecognised dietary micronutrient required for healthy ageing?

Ergothioneine is a naturally occurring amino acid and thiol antioxidant found in high amounts in mushrooms and fermented foods. Humans and animals acquire ergothioneine from the diet through the pH-dependent activity of a membrane transporter, the large solute carrier 22A member 4 (SLC22A4), expressed on the apical membrane of the small intestine. The SLC22A4 transporter also functions in the renal reabsorption of ergothioneine in the kidney, with avid absorption and retention of ergothioneine from the diet observed in both animals and humans. Ergothioneine is capable of scavenging a diverse range of reactive oxygen and nitrogen species, has metal chelation properties, and is predicted to directly regulate nuclear factor erythroid 2-related factor 2 (Nrf2) activity. Although not lethal, the genetic knockout of the SLC22A4 gene in multiple organisms increases susceptibility to oxidative stress, damage and inflammation; in agreement with a large body of preclinical data suggesting the physiological function of ergothioneine is as a cellular antioxidant and cytoprotectant agent. In humans, blood levels of ergothioneine decline after the age of 60 years, and lower levels of ergothioneine are associated with more rapid cognitive decline. Conversely, high plasma ergothioneine levels have been associated with significantly reduced cardiovascular mortality and overall mortality risks. In this horizon’s manuscript, we review evidence suggesting critical roles for dietary ergothioneine in healthy ageing and the prevention of cardiometabolic disease. We comment on some of the outstanding research questions in the field and consider the question of whether or not ergothioneine should be considered a conditionally essential micronutrient.

Development and validation of a quality assessment tool to assess online nutrition information

Setting

The internet is an important source of health information but is unregulated. Little research has focused on the assessment of digital information related to nutrition.

Aim

To develop and validate a novel online quality assessment tool (OQAT) for quality assessment of online nutrition information.

Method

The OQAT was developed and validated in six distinct stages. After reviewing the literature, a framework and criteria were developed and formalised. Next, the quality assessment criteria were piloted on a subset of data and criteria refined. The established criteria were then validated against a previously validated assessment tool, and reliability was tested. Finally, the validated OQAT was used to assess the quality of articles from a 24-h collection period, 19 April 2021.

Results

The final OQAT consisted of 10 key questions. Twenty-six news articles were assessed independently by two raters. Comparison of scores found moderate internal consistency (α = 0.382). Cohen's Kappa coefficient demonstrated high interrater agreement (k = 0.653, p < 0.001). The OQAT was tested on 291 relevant Uniform Resource Locators (URLs), which were determined to be either poor 3% (n = 9), satisfactory 49% (n = 144), or high-quality 48% (n = 139) articles. There was a statistically significant difference in OQAT scores between blogs, news articles, and press releases, χ2(2) = 23.22, p < 0.001, with a mean rank OQAT score of 138.2 for blogs, 216.6 for news articles, and 188.7 for press releases.

Conclusion

This novel tool provides a reliable and objective method for assessing the quality of nutrition content online. It could potentially be used by researchers to assess the quality of online information in different settings and by organisations to inform readers of the quality of information being accessed.

In the context of the triple burden of malnutrition: A systematic review of gene-diet interactions and nutritional status

Genetic background interacts with dietary components to modulate nutritional health status. This study aimed to review the evidence for gene-diet interactions in all forms of malnutrition. A comprehensive systematic literature search was conducted through April 2021 to identify observational and intervention studies reporting the effects of gene-diet interactions in over-nutrition, under-nutrition and micronutrient status. Risk of publication bias was assessed using the Quality Criteria Checklist and a tool specifically designed for gene-diet interaction research. 167 studies from 27 populations were included. The majority of studies investigated single nucleotide polymorphisms (SNPs) in overnutrition (n = 158). Diets rich in whole grains, vegetables, fruits and low in total and saturated fats, such as Mediterranean and DASH diets, showed promising effects for reducing obesity risk among individuals who had higher genetic risk scores for obesity, particularly the risk alleles carriers of FTO rs9939609, rs1121980 and rs1421085. Other SNPs in MC4R, PPARG and APOA5 genes were also commonly studied for interaction with diet on overnutrition though findings were inconclusive. Only limited data were found related to undernutrition (n = 1) and micronutrient status (n = 9). The findings on gene-diet interactions in this review highlight the importance of personalized nutrition, and more research on undernutrition and micronutrient status is warranted.

Unique Metabolic Profiles Associate with Gestational Diabetes and Ethnicity in Low- and High-Risk Women Living in the UK

BACKGROUND

Gestational diabetes mellitus (GDM) is the most common global pregnancy complication; however, prevalence varies substantially between ethnicities, with South Asians (SAs) experiencing up to 3 times the risk of the disease compared with white Europeans (WEs). Factors driving this discrepancy are unclear, although the metabolome is of great interest as GDM is known to be characterized by metabolic dysregulation.

OBJECTIVES

The primary aim was to characterize and compare the metabolic profiles of GDM in SA and WE women (at <28 wk of gestation) from the Born in Bradford (BIB) prospective birth cohort in the United Kingdom.

METHODS

In total, 146 fasting serum metabolites, from 2,668 pregnant WE and 2,671 pregnant SA women (average BMI 26.2 kg/m2, average age 27.3 y) were analyzed using partial least squares discriminatory analyses to characterize GDM status. Linear associations between metabolite values and post-oral glucose tolerance test measures of dysglycemia (fasting glucose and 2 h postglucose) were also examined.

RESULTS

Seven metabolites associated with GDM status in both ethnicities (variable importance in projection ≥1), whereas 6 additional metabolites associated with GDM only in WE women. Unique metabolic profiles were observed in healthy-weight women who later developed GDM, with distinct metabolite patterns identified by ethnicity and BMI status. Of the metabolite values analyzed in relation to dysglycemia, lactate, histidine, apolipoprotein A1, HDL cholesterol, and HDL2 cholesterol associated with decreased glucose concentration, whereas DHA and the diameter of very low-density lipoprotein particles (nm) associated with increased glucose concertation in WE women, and in SAs, albumin alone associated with decreased glucose concentration.

CONCLUSIONS

This study shows that the metabolic risk profile for GDM differs between WE and SA women enrolled in BiB in the United Kingdom. This suggests that etiology of the disease differs between ethnic groups and that ethnic-appropriate prevention strategies may be beneficial.

Lack of PI 3-kinase isoform p110alpha impairs SMC differentiation and proliferation and promotes aortic aneurysm formation

Background

Proliferation and phenotypic modulation of vascular smooth muscle cells (SMCs) significantly contribute to the functionality of the aortic wall. Dysregulation of underlying signal transduction pathways impairs the vessel wall structure and promote the development and progression of abdominal aortic aneurysms (AAA). The PI 3-kinase (PI3K) isoform p110α is activated downstream of receptor tyrosine kinases (RTKs) and represents the most relevant PI3K isoform in SMCs.

Aim

This project follows the hypothesis that p110α deficiency impairs proliferation and phenotypic modulation of SMCs as well as the structure of the extracellular matrix (ECM) and therefore promotes the development and progression of AAA. It was investigated how p110α deficiency affects the plasticity of SMCs, the production and structure of ECM components, and the formation of AAA.

Methods and results

Western blot analyses showed that SMCs isolated from smooth muscle specific p110α−/− (sm-p110α−/−) mice were characterized by decreased expression of the differentiation markers sm-α-actin, calponin and sm-MHC. Mechanistically, phosphorylation of key modulators of the SMC phenotype – AKT1, AKT2, FOXO1, -3 and -4 as well as GSK3β – was impaired in p110α−/− SMCs after RTK stimulation. These findings indicate that phenotypic modulation of p110α−/− SMCs is restricted. In addition, protein expression of elastin and fibrillin was reduced in p110α−/− SMCs. In silico analysis (MatLab macro CT-FIRE and Curvalign) of the ECM produced by SMCs in vitro revealed a significantly reduced elastin fiber length and width in p110α−/− SMCs compared to fibers produced by WT SMCs (p&lt;0.05). Consistently, aortas from sm-p110α−/− mice showed a significantly higher number of elastic fiber breaks specifically in the thoracic section than WT controls (289±31 mmm–2 versus 190±9 mmm–2, n=5, p=0.015). Aortic aneurysms in sm-p110α−/− mice and wild-type littermates were analyzed using the established porcine pancreatic elastase (PPE) model. PPE was perfused into the infrarenal aorta to induce AAA formation. Ultrasound examination of the aorta revealed an enlarged aortic diameter in all PPE-treated mice. However, the increase in aortic diameter in sm-p110α−/− mice (70.16±10.82% mm, n=9) was significant more pronounced compared to wild-type animals (42.44±5.99%, n=10) (p&lt;0.05). Three days after PPE perfusion, the number of elastic fiber breaks was significantly increased, and amount of proliferating SMCs were decreased in the infrarenal aorta of sm-p110α−/− mice compared to WT controls.

Conclusion

p110α deficiency in SMCs impairs aortic wall structure and promotes the development and progression of aortic aneurysms. Mechanistically, p110α activity maintains a differentiated SMC phenotype as well as the expression and assembly of ECM components. These data identify p110α signaling as a modifiable target for preventive and therapeutic strategies for aortic aneurysms.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Deutsche Forschungsgemeinschaft

Putting nutrition education on the table: development of a curriculum to meet future doctors' needs

COVID-19 has further exacerbated trends of widening health inequalities in the UK. Shockingly, the number of years of life lived in general good health differs by over 18 years between the most and least deprived areas of England. Poor diets and obesity are established major risk factors for chronic cardiometabolic diseases and cancer, as well as severe COVID-19. For doctors to provide the best care to their patients, there is an urgent need to improve nutrition education in undergraduate medical school training.With this imperative, the Association for Nutrition established an Interprofessional Working Group on Medical Education (AfN IPG) to develop a new, modern undergraduate nutrition curriculum for medical doctors. The AfN IPG brought together expertise from nutrition, dietetic and medical professionals, representing the National Health Service (NHS), royal colleges, medical schools and universities, government public health departments, learned societies, medical students, and nutrition educators. The curriculum was developed with the key objective of being implementable through integration with the current undergraduate training of medical doctors.Through an iterative and transparent consultative process, thirteen key nutritional competencies, to be achieved through mastery of eleven graduation fundamentals, were established. The curriculum to facilitate the achievement of these key competencies is divided into eight topic areas, each underpinned by a learning objective statement and teaching points detailing the knowledge and skills development required. The teaching points can be achieved through clinical teaching and a combination of facilitated learning activities and practical skill acquisition. Therefore, the nutrition curriculum enables mastery of these nutritional competencies in a way that will complement and strengthen medical students' achievement of the General Medical Council (GMC) Outcome for Graduates.As nutrition is an integrative science, the AfN IPG recommends that the curriculum is incorporated into initial undergraduate medical studies before specialist training. This will enable our future doctors to recognise how nutrition is related to multiple aspects of their training, from physiological systems to patient-centred care, and acquire a broad, inclusive understanding of health and disease. In addition, it will facilitate medical schools to embed nutrition learning opportunities within the core medical training, without the need to add in a large number of new components to an already crowded programme or with additional burden for teaching staff.The undergraduate nutrition curriculum for medical doctors is designed to support medical schools to create future doctors who will understand and recognise the role of nutrition in health. Moreover, it will equip frontline staff to feel empowered to raise nutrition-related issues with their patients as a fundamental part of enhanced care and to appropriately refer on for nutrition support with a registered associate nutritionist/registered nutritionist (ANutr/RNutr) or registered dietitian (RD) where this is likely to be beneficial.

Putting nutrition education on the table: development of a curriculum to meet future doctors' needs

COVID-19 has further exacerbated trends of widening health inequalities in the UK. Shockingly, the number of years of life lived in general good health differs by over 18 years between the most and least deprived areas of England. Poor diets and obesity are established major risk factors for chronic cardiometabolic diseases and cancer, as well as severe COVID-19. For doctors to provide the best care to their patients, there is an urgent need to improve nutrition education in undergraduate medical school training. With this imperative, the Association for Nutrition established the Inter-Professional Working Group on Medical Education (AfN IPG) to develop a new, modern undergraduate nutrition curriculum for medical doctors. The AfN IPG brought together expertise from nutrition, dietetic and medical professionals, representing the National Health Service, royal colleges, medical schools and universities, government public health departments, learned societies, medical students and nutrition educators. The curriculum was developed with the key objective of being implementable through integration with the current undergraduate training of medical doctors. Through an iterative and transparent consultative process, 13 key nutritional competencies, to be achieved through mastery of 11 graduation fundamentals, were established. The curriculum to facilitate the achievement of these key competencies is divided into eight topic areas, each underpinned by a learning objective statement and teaching points detailing the knowledge and skills development required. The teaching points can be achieved through clinical teaching and a combination of facilitated learning activities and practical skills acquisition. Therefore, the nutrition curriculum enables mastery of these nutritional competencies in a way that will complement and strengthen medical students' achievement of the General Medical Council Outcomes for Graduates. As nutrition is an integrative science, the AfN IPG recommends the curriculum is incorporated into initial undergraduate medical studies before specialist training. This will enable our future doctors to recognise how nutrition is related to multiple aspects of their training, from physiological systems to patient-centred care, and acquire a broad, inclusive understanding of health and disease. In addition, it will facilitate medical schools to embed nutrition learning opportunities within the core medical training, without the need to add in a large number of new components to an already crowded programme or with additional burden to teaching staff. The undergraduate nutrition curriculum for medical doctors is designed to support medical schools to create future doctors who will understand and recognise the role of nutrition in health. Moreover, it will equip front-line staff to feel empowered to raise nutrition-related issues with their patients as a fundamental part of enhanced care and to appropriately refer on for nutrition support with a registered nutritionist (RNutr)/registered associate nutritionist (ANutr) or a registered dietitian (RD) where this is likely to be beneficial.

Associations between liver X receptor polymorphisms and blood lipids: A systematic review and meta-analysis

Genetic susceptibility to dyslipidaemia remains incompletely understood. The liver X receptors (LXRs), members of the nuclear receptor superfamily of ligand dependent transcription factors, are homeostatic regulators of lipid metabolism. Multiple single nucleotide polymorphisms (SNPs)have been identified previously in the coding and regulatory regions of the LXRs. The aim of this systematic review and meta-analysis was to summarise associations between SNPs of LXRs (α and β isoforms) with blood lipid and lipoprotein traits. Five databases (PubMed, Ovid Embase, Scopus, Web of Science, and the Cochrane Library) were systematically searched for population-based studies that assessed associations between one or more blood lipid/lipoprotein traits and LXR SNPs. Of seventeen articles included in the qualitative synthesis, ten were eligible for meta-analysis. Nine LXRα SNPs and five LXRβ SNPs were identified, and the three most studied LXRα SNPs were quantitatively summarised. Carriers of the minor allele A of LXRα rs12221497 (-115G>A) had higher triglyceride levels than GG homozygotes (0.13 mmol/L; 95%CI: [0.03, 0.23], P = 0.01). Heterozygote carriers of LXRα rs2279238 (297C/T) had higher total cholesterol levels (0.12 mmol/L; (95%CI: [0.01, 0.23], P = 0.04) than either CC or TT homozygotes. For LXRα rs11039155 (-6G>A), no significant differences in blood levels of either triglyceride (P = 0.39) or HDL-C (P = 0.98) were detected between genotypes in meta-analyses. In addition, there were no strong associations for other SNPs of LXRα and LXRβ. This study provides the evidence of an association between LXRα, but not LXRβ, SNPs and blood-lipid traits. Systematic review registration: PROSPERO No. CRD42021246158.

A Cross-Sectional Observational Study of Online Pre-order Systems for School Lunches in Primary Schools

Objectives

To explore how children (4–11 years) interact with online pre-order systems (OPS) to select school lunches.

Methods

A combination of direct observation and an online questionnaire was used to examine the operation of OPS in four UK primary schools. An observation form was developed to collect data on how the menu options were displayed on the OPS, how children selected options, and the interactions between children and others when making food selections. A questionnaire was used to collect data on parent's perspectives on their children's school food choices and the OPS. Descriptive statistics were followed by Fisher's exact tests to examine associations between characteristics (e.g., year group) and outcomes such as having a school lunch or who the decision-maker was. Qualitative data were analysed using a thematic approach.

Results

Twelve hours of direct observation in 24 classrooms with children aged 4–11 years (n = 682) were conducted. The food displayed on the systems differed across the systems and schools, reflecting the schools’ respective menu cycles. Most children (70%) having school lunches pre-ordered these in the classroom (the alternative was remote selection with a parent account). Differences in the food choice process related to children's ages; older children (8–11 years) were observed to be more independent when making food selections, compared to younger children, often supported by parents or teachers. The questionnaire was completed by 125 parents and over half of the parents (54%) of children having a school lunch reported that their child was the decision-maker when choosing the menu option. Interestingly, there was a significant association between year group and who chose the lunch option from the menu (p = 0.007), with a moderate effect size. Three main themes emerged from 151 comments from parents, including those related to children's independence when choosing lunch and parents viewing this as part of children growing up.

Conclusions

Observation was invaluable in understanding the OPS and how pupils chose their meals. Given the potential expansion of these systems in schools, there is an opportunity to develop interventions to guide children towards specific or different options from the school menu.

Funding Sources

Princess Nourah Bint Abdulrahman University, KSA.

Ethnic-specific associations between dietary consumption and gestational diabetes mellitus incidence: A meta-analysis

Globally, one in seven pregnant women are diagnosed with gestational diabetes mellitus (GDM), conferring short- and long-term health risks to both mother and child. While dietary prevention strategies are common in clinical practice, their effectiveness in different ethnicities is uncertain. To better inform prevention strategies, here the effects of unhealthy and healthy diets on GDM risk within distinct ethnic or cultural populations and geographic regions were evaluated and summarised. Pubmed, Scopus, Cochrane and OVID were systematically searched to identify randomised controlled trials (RCTs) and observational studies that investigated diet and GDM. A grouped analysis of common 'healthy' and 'unhealthy' diets was performed first, before analysing individual dietary patterns (e.g., prudent, Mediterranean). Random effect models and dose response analyses were performed where possible. PROSPERO (CRD42019140873). Thirty-eight publications provided information on 5 population groups: white European (WE), Asian, Iranian, Mediterranean and Australian. No associations were identified between healthy diets and GDM incidence in RCTs in any population. However, when synthesizing observational studies, healthy diets reduced odds of GDM by 23% (95% CI: 0.70-0.89, p<0.001, I2 = 75%), while unhealthy diets increased odds of GDM by 61% (95% CI: 1.41-1.81, p<0.0001, I2 = 0%) in WE women. No evidence of consistent effects in other populations were observed, even when adequately powered. Diet consistently associated with GDM risk in WEs but not in other populations. Heterogenous use and reporting of ethnically and culturally appropriate diets and dietary assessment tools, particularly in RCTs, raises uncertainty regarding the lack of association found in non-WE populations. Future studies require the use of culturally appropriate tools to confidently evaluate dietary and metabolic mediators of GDM and inform culturally-specific dietary prevention strategies.

Investigation of the Association between High Arachidonic Acid Synthesis and Colorectal Polyp Incidence within a Generally Healthy UK Population: A Mendelian Randomization Approach

BACKGROUND

Arachidonic acid (ARA) is associated with colorectal cancer (CRC), a major public health concern. However, it is uncertain if ARA contributes to the development of colorectal polyps which are pre-malignant precursors of CRC.

OBJECTIVE

The study aimed to investigate the association between lifelong exposure to elevated ARA and colorectal polyp incidence.

METHODS

Summary-level GWAS data from European, Singaporean, and Chinese cohorts (n = 10,171) identified 4 single-nucleotide polymorphisms (SNPs) associated with blood ARA levels (p < 5 × 10-8). After pruning, 1 SNP was retained (rs174547; p = 3.0 × 10-971) for 2-stage Mendelian randomization.

RESULTS

No association between ARA and colorectal polyp incidence was observed (OR = 1.00; 95% CI: 0.99, 1.00; p value = 0.50) within the UK Biobank (1,391 cases; 462,933 total).

CONCLUSIONS

Blood levels of ARA do not associate with colorectal polyp incidence in a general healthy population. Although not providing direct evidence, this work supports the contention that downstream lipid mediators, such as PGE2 rather than ARA itself, are key for polyp formation during early-stage colorectal carcinogenesis.

The role of motivation on physical activity and screen time behaviors among parent-adolescent dyads: The FLASHE study

Behavioral theories inform the development of lifestyle interventions to address low participation in physical activity (PA); however, relatively little is known about the value of self-determination theory (SDT) for explaining screen time (ST) behaviors or in extending SDT into a dyadic context. Actor-partner (i.e., parent-adolescent) interdependence models (APIMs) allow for examination of these interpersonal relationships. The purpose of this study was to examine PA and ST among parent-adolescent dyads using the cross-sectional Family Life, Activity, Sun, Health, and Eating (FLASHE) Study. Parent-adolescent dyads provided responses to online surveys addressing PA (n = 1177 dyads) and ST (n = 1489 dyads) behaviors. We examined the influence of SDT-based constructs (perceived competence and motivation) on PA and ST behaviors. Structural equations were used to estimate APIMs in STATA 15.1. Full models provided a good fit to the data. For both PA and ST, perceived competence was more strongly associated with motivation among adolescents compared with parents (PA: β = 0.72 vs. 0.58, ST: β = 0.34 vs. 0.22, p's < 0.001). Parental motivation was associated with parental PA and both adolescent motivation for PA and ST (p's < 0.001). Parental motivation was not associated with adolescent ST-behavior. Adolescent motivation was only associated with parent motivation for PA. In the FLASHE study, SDT constructs extend acceptably to the dyadic setting, with PA models providing a slightly better fit to the data than ST models. Longitudinal studies that target perceived competence and the self-regulation of motivation in parents and their adolescents are a next logical step to understanding both PA and ST behaviors.

Changes in Physical Activity and Television Viewing From Pre-pregnancy Through Postpartum Among a Socioeconomically Disadvantaged Perinatal Adolescent Population

STUDY OBJECTIVE

Adolescent pregnancy contributes to accelerated trajectories of adiposity and cardiometabolic diseases. Two potentially low-cost prevention strategies include promoting physical activity (PA) and limiting television (TV) viewing. Few studies have explored these behavior patterns in perinatal adolescents. This study sought to characterize PA and TV viewing in a socioeconomically disadvantaged perinatal adolescent population.

DESIGN, SETTING, PARTICIPANTS, AND INTERVENTIONS

A cross-sectional, retrospective, 10-item survey was used to explore behavior patterns in 79 predominantly Black (86%) postpartum adolescents.

MAIN OUTCOME MEASURES

Outcomes included self-reported changes in PA from pre-pregnancy through pregnancy, and 7-day recall of PA and TV viewing in postpartum.

RESULTS

The majority of adolescents (66%) reported being active on ≥3 days/week in pre-pregnancy; however, many reported low PA (≤2 days/wk) in their first (59%), second (66%), and third (54%) trimesters. Adolescents who reported being active on ≥5 days/wk in pre-pregnancy (19%) experienced first trimester PA decline, which subsequently plateaued. This group remained the most active throughout pregnancy. In postpartum, over half (54%) of all adolescents reported low PA and irrespective of PA, spent considerable time watching TV (median = 1680.0 minutes, inerquartile range = 2940).

CONCLUSION

Interventions promoting PA coupled with reducing TV viewing during pregnancy and in postpartum may benefit perinatal adolescents. The findings from this study suggest that PA history is a predictor of gestational PA, and low PA and high TV viewing in postpartum underscore the need for behavioral intervention. Conducting a brief assessment of PA history in early gestation may offer important insight.

Dietary carbohydrates and fats in nonalcoholic fatty liver disease

The global prevalence of nonalcoholic fatty liver disease (NAFLD) has dramatically increased in parallel with the epidemic of obesity. Controversy has emerged around dietary guidelines recommending low-fat-high-carbohydrate diets and the roles of dietary macronutrients in the pathogenesis of metabolic disease. In this Review, the topical questions of whether and how dietary fats and carbohydrates, including free sugars, differentially influence the accumulation of liver fat (specifically, intrahepatic triglyceride (IHTG) content) are addressed. Focusing on evidence from humans, we examine data from stable isotope studies elucidating how macronutrients regulate IHTG synthesis and disposal, alter pools of bioactive lipids and influence insulin sensitivity. In addition, we review cross-sectional studies on dietary habits of patients with NAFLD and randomized controlled trials on the effects of altering dietary macronutrients on IHTG. Perhaps surprisingly, evidence to date shows no differential effects between free sugars, with both glucose and fructose increasing IHTG in the context of excess energy. Moreover, saturated fat raises IHTG more than polyunsaturated or monounsaturated fats, with adverse effects on insulin sensitivity, which are probably mediated in part by increased ceramide synthesis. Taken together, the data support the use of diets that have a reduced content of free sugars, refined carbohydrates and saturated fat in the treatment of NAFLD.

Ergothioneine supplementation in people with metabolic syndrome (ErgMS): protocol for a randomised, double-blind, placebo-controlled pilot study

Background

Ergothioneine is a naturally occurring metabolite of histidine found in many foods and in high amounts in mushrooms. In vivo, ergothioneine acts as an antioxidant and is widely distributed in most mammalian tissues. While ergothioneine is sold as a dietary supplement for its antioxidant and anti-inflammatory properties, to date there are no published intervention trials examining its health benefits in humans. The aim of this work was to develop a study protocol for a pilot interventional trial that will establish the primary and secondary outcomes, and the power required, for a definitive randomised controlled trial to test the hypothesis that ergothioneine supplementation is beneficial for people with metabolic syndrome.

Methods

We have designed the ErgMS study as a single-centre, randomised, double-blind, placebo-controlled, 3-arm parallel, pilot intervention trial, which aims to supplement participants with either placebo, 5 or 30 mg/day ergothioneine for 12 weeks. Measurements of metabolic syndrome risk factors, serum markers of oxidative stress (lipid peroxidation), inflammation, blood platelet function and liver function will take place at baseline, and after 6 weeks and 12 weeks of supplementation. In addition, we will examine if there are any changes in the serum metabolome in response to ergothioneine supplementation. Linear regression and two-way ANOVA will be utilised to analyse the association between ergothioneine and measured variables.

Discussion

The ErgMS study will be the first study to address the question does ergothioneine supplementation have health benefits for people with metabolic syndrome. Study results will provide preliminary data as to which dose may improve inflammatory markers in adults with metabolic syndrome and will inform dose and primary outcome selection for a definitive randomised controlled trial.

Trial registration

ISRCTN, ISRCTN25890011 Registered February 10^th, 2021

Supplementary Information

The online version contains supplementary material available at 10.1186/s40814-021-00929-6.

Characterization and prognostic value of LXR splice variants in triple-negative breast cancer

Activity of liver x receptor (LXR), the homeostatic regulator of cholesterol metabolism, is elevated in triple-negative breast cancer (BCa) relative to other BCa subtypes, driving drug resistance and metastatic gene signatures. The loci encoding LXRα and LXRβ produce multiple alternatively spliced proteins, but the true range of variants and their relevance to cancer remain poorly defined. Here, we report seven LXR splice variants, three of which have not previously been reported and five that were prognostic for disease-free survival. Expression of full-length LXRα splice variants was associated with poor prognosis, consistent with a role as an oncogenic driver of triple-negative tumor pathophysiology. Contrary to this was the observation that high expression of truncated LXRα splice variants or any LXRβ splice variant was associated with longer survival. These findings indicate that LXR isoform abundance is an important aspect of understanding the link between dysregulated cholesterol metabolism and cancer pathophysiology.

Distinct Serum Metabolic Profiles in Early Pregnancy Characterise Gestational Diabetes Mellitus Incidence in High-Risk Women

Objectives

This study aimed to investigate and characterise the metabolic profiles of gestational diabetes mellitus (GDM) in white European (WE) and British Pakistani (BP) women with and without GDM.

Methods

146 serum metabolites quantified by nuclear magnetic resonance, from 2668 WEs and 2671 BP pregnant women ≤28 weeks’ gestation from the Born in Bradford cohort were analysed. Partial least squares discriminatory analyses (PLSDA) and sparse PLSDA (sPLSDA) were used to investigate the ethnic-specific metabolite signatures of future incidence of GDM. Metabolite features driven by pre-pregnancy weight status and known GDM risk factors (age, parity, multiple pregnancies and smoking status) were also explored.

Results

Models explained 60% of variance between future GDM cases/non-cases in WE mothers but only 35% in BPs, after adjusting for BMI, age, parity, smoking, and non-singleton pregnancies. Across both ethnic groups, 8 metabolites associated with future GDM status. When ethnic groups were investigated independently, 7 additional metabolites associated with future GDM in WEs were identified, while no additional associations were observed in BPs. Further stratification by BMI (healthy vs overweight/obese) uncovered a metabolic profile (characterised by fatty acids and glycolytic metabolites) unique to normal-weight BP women who later developed GDM. No difference was observed between the metabolic profiles of overweight/obese women, irrespective of ethnicity.

Conclusions

In early pregnancy, the metabolomes of future GDM cases and non-cases are distinct and differ by ethnicity. While the metabolic profiles of overweight women are largely similar in WE and BPs, a unique metabolic profile was observed in healthy weight BP women who went on to develop GDM and offers insight into the early metabolomic perturbations that precede GDM development in this high-risk (but healthy) population. Further exploration regarding the interaction between genetics and lifestyle on modifying metabolic profiles associated with GDM risk will help inform ethnically appropriate nutrition strategies.

Funding Sources

HF is supported by a doctoral scholarship from the University of Leeds.

Liver x receptor alpha drives chemoresistance in response to side-chain hydroxycholesterols in triple negative breast cancer

Triple negative breast cancer (TNBC) is challenging to treat successfully because targeted therapies do not exist. Instead, systemic therapy is typically restricted to cytotoxic chemotherapy, which fails more often in patients with elevated circulating cholesterol. Liver x receptors are ligand-dependent transcription factors that are homeostatic regulators of cholesterol, and are linked to regulation of broad-affinity xenobiotic transporter activity in non-tumor tissues. We show that LXR ligands confer chemotherapy resistance in TNBC cell lines and xenografts, and that LXRalpha is necessary and sufficient to mediate this resistance. Furthermore, in TNBC patients who had cancer recurrences, LXRalpha and ligands were independent markers of poor prognosis and correlated with P-glycoprotein expression. However, in patients who survived their disease, LXRalpha signaling and P-glycoprotein were decoupled. These data reveal a novel chemotherapy resistance mechanism in this poor prognosis subtype of breast cancer. We conclude that systemic chemotherapy failure in some TNBC patients is caused by co-opting the LXRalpha:P-glycoprotein axis, a pathway highly targetable by therapies that are already used for prevention and treatment of other diseases.

Improvement in histological endpoints of MAFLD following a 12-week aerobic exercise intervention

BACKGROUND

Lifestyle interventions are the primary treatment for metabolic (dysfunction) associated fatty liver disease (MAFLD). However, the histological and cardiometabolic effects of aerobic exercise in MAFLD remain unclear.

AIMS

To assess the effects of a 12-week aerobic exercise intervention on histological and cardiometabolic endpoints in MAFLD.

METHODS

Patients with biopsy-confirmed MAFLD participated in a 12-week aerobic exercise intervention. Liver histology, cardiorespiratory fitness (estimated V̇O_2max ), physical activity, anthropometry and biochemical markers were assessed at baseline, intervention completion, and 12 and 52 weeks after intervention completion.

RESULTS

Twenty-four patients completed the exercise intervention (exercise group n = 16, control group n = 8). In the exercise group, 12 weeks of aerobic exercise reduced fibrosis and hepatocyte ballooning by one stage in 58% (P = 0.034) and 67% (P = 0.020) of patients, with no changes in steatosis (P = 1.000), lobular inflammation (P = 0.739) or NAFLD activity score (P = 0.172). Estimated V̇O_2max increased by 17% compared to the control group (P = 0.027) but this level of improvement was not maintained at 12 or 52 weeks after the intervention. Patients with fibrosis and ballooning improvement increased estimated V̇O_2max by 25% (P = 0.020) and 26% (P = 0.010), respectively. Anthropometric reductions including body mass (P = 0.038), waist circumference (P = 0.015) and fat mass (P = 0.007) were also observed, but no patient achieved 7%-10% weight loss.

CONCLUSION

This study highlights the potential benefits of a 12-week aerobic exercise intervention in improving histological endpoints of MAFLD. The development of strategies to ensure continued engagement in aerobic exercise in MAFLD are needed.

Implementation of a Community Walking Program (Walk On!) for Functionally-Limited Older Adults

BACKGROUND

Walking interventions improve physical function, reduce fall risk, and prevent mobility disability-even in those with compromised walking ability. However, most prior studies have been conducted in controlled research settings, with no dissemination of an evidence-based walking program for older adults who have mobility limitations and/or are socially isolated.

OBJECTIVES

This study reports data on the feasibility and acceptability of a community-based walking program (Walk On!) for older adults who are functionally limited, and assesses changes in physical function among attendees. The program sessions focused on long-distance walking, and took place for one-hour, for two days/week, and for 12 weeks at a time.

DESIGN

Pilot implementation study.

SETTING

Local church in Winston-Salem, NC.

PARTICIPANTS

49 program participants; Measurements: Physical function battery and satisfaction survey data, as well as formative evaluation data from six attendees of a focus group, are reported.

RESULTS

The majority of the participants were >75 years (71%), female (65%), and presented with low levels of physical function (usual gait speed=0.79±0.16; 30.6% used an assistive device). Satisfaction with the program was high (100% would recommend it to others) and focus group results were overwhelmingly positive. Mean attendance to scheduled sessions was 77%±21%, and 63% of participants attended at least 75% of scheduled sessions (n=8 attended 100%). On average, participants improved their 6-min walk distance by 8.9%, their SPPB score by 15.4%, their timed-up-go time by 9.0%, and their usual gait speed by 11.4%.

CONCLUSION

The results of the initial evaluation of Walk On! show high feasibility and acceptability of the program, as well as efficacy for improving physical function. Further research is needed to evaluate a delivery method for wider implementation of the program and to definitively test its effectiveness for improving function and other health benefits.

Vitamin D and nonalcoholic fatty liver disease

PURPOSE OF REVIEW

Vitamin D deficiency may impact disease progression of nonalcoholic fatty liver disease (NAFLD). The aim of this work was to review recent studies examining either vitamin D status or the effects of supplementation in patients with NAFLD, along with investigating the roles of genetic polymorphisms and the gut microbiome.

RECENT FINDINGS

Six heterogeneous observational studies of vitamin D status, and four randomized controlled intervention trials of vitamin D supplementation in NAFLD were conflicting. All studies were hampered by the challenges of diagnosing NAFLD, were underpowered, and lacked data on clinically important outcomes. The results of three cross-sectional studies, including a Mendelian randomization study, provide limited evidence for a role for genetic modifiers of vitamin D status in NAFLD. Genetic and experimental evidence suggests that vitamin D and the vitamin D receptor (VDR) may influence the gut microbiome in health and disease.

SUMMARY

The evidence relating either lower vitamin D status to the prevalence and severity of NAFLD, or examining vitamin D supplementation in patients with NAFLD is inconclusive. Larger, higher quality trials with relevant endpoints are needed. Further mechanistic studies on the roles of vitamin D and VDR in influencing the gut-liver axis in NAFLD are warranted.

Development and relative validation of a short food frequency questionnaire for assessing dietary intakes of non-alcoholic fatty liver disease patients

Purpose

This work aimed to design and validate a novel short food frequency questionnaire (SFFQ) to assess habitual intakes of food items related to non-alcoholic fatty liver disease (NAFLD) in a cohort of European patients.

Methods

A 48-item SFFQ was created, with questions from existing FFQs and expert knowledge, emphasizing foods and nutrients implicated in NAFLD pathogenesis. Consenting, fibroscan-diagnosed, NAFLD patients completed the SFFQ during a short interview and were asked to complete a 4-day diet diary (4DDD) at home for return by mail. Nutritional intakes were assessed utilizing the myfood24™ food composition dataset and estimated energy requirements (EER) were calculated using sex-, age- and weight-specific equations. Agreement between the dietary instruments was assessed by Spearman correlations and Bland Altman analysis.

Results

Fifty-five patients completed both the SFFQ and the 4DDD within 30 weeks; 42 (76%) were diagnosed with simple steatosis, whereas 13 (24%) had biopsy-proven steatohepatitis; the majority were overweight or obese, with a median (25th; 75th percentile) BMI of 33.2 kg/m² (29.3; 36.0). Reported energy intakes were well below EER with a median intake of 73% of requirements, suggesting widespread under-reporting. Significant correlations were observed between sugar (r = 0.408, P = 0.002), fat (r = 0.44, P = 0.001), fruits (r = 0.51, P = 0.0001) and vegetables (r = 0.40, P = 0.0024) measurements by the SFFQ and 4DDD. Bland Altman plots with regression analysis demonstrated broad comparability with the 4DDD for intakes of fat (bias − 13.8 g/day) and sugar (bias  + 12.9 g/day).

Conclusions

A novel SFFQ designed to be minimally burdensome to participants was effective at assessing dietary intakes in NAFLD patients.

Electronic supplementary material

The online version of this article (10.1007/s00394-019-01926-5) contains supplementary material, which is available to authorized users.

Evaluation of the nutrient content of yogurts: a comprehensive survey of yogurt products in the major UK supermarkets

OBJECTIVES

To comprehensively survey the sugar and nutrient contents of yogurt products available in UK supermarkets, in particular those marketed to children.

DESIGN

A cross-sectional survey of yogurt products available in the UK's supermarkets in November 2016.

METHODS

Data were collected from five major online UK supermarkets and a process flow strategy was used to place yogurts into eight categories: children's, dairy alternatives, dessert, drinks, fruit, flavoured, natural/Greek style and organic. A comprehensive database of product information for 921 unique products was created and analysed.

RESULTS

The total sugar, fat, protein, calcium and energy contents were highly variable across categories, and the ranges were extremely broad. Although lower than the dessert category, the medians (range) of the total sugar content of children's (10.8 g/100 g (4.8-14.5)), fruit (11.9 g/100 g (4.6-21.3)), flavoured (12.0 g/100 g (0.1-18.8)) and organic (13.1 g/100 g (3.8-16.9)) yogurt products were all well above 10 g/100 g, and represented >45% of total energy. Only two out of 101 children's yogurt and fromage frais products surveyed qualified as low sugar (≤5 g/100 g). Natural/Greek yogurts had dramatically lower sugar contents (5.0 g/100 g (1.6, 9.5), largely lactose) than all other categories. While low-fat (<3 g/100 g) products had less sugar and energy than higher fat yogurts, nonetheless 55% (285 of 518 low-fat yogurts) contained between 10 and 20 g sugar/100 g. Within the children's category, fromage frais had higher protein (5.3 g/100 g (3.3, 8.6) vs 3.2 (2.8, 7.1); p<0.0001) and calcium contents (150 mg/100 g (90, 240) vs 130.5 mg/100 g (114, 258); p=0.0015) than yogurts.

CONCLUSIONS

While there is good evidence that yogurt can be beneficial to health, products on the market vary widely in total sugars. Fewer than 9%, and only 2% of the children's, products surveyed were low enough in sugar to earn 'green' in UK front of the pack labelling. Reformulation for the reduction of free sugars in yogurts is warranted.

Multi-scale, whole-system models of liver metabolic adaptation to fat and sugar in non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is a serious public health issue associated with high fat, high sugar diets. However, the molecular mechanisms mediating NAFLD pathogenesis are only partially understood. Here we adopt an iterative multi-scale, systems biology approach coupled to in vitro experimentation to investigate the roles of sugar and fat metabolism in NAFLD pathogenesis. The use of fructose as a sweetening agent is controversial; to explore this, we developed a predictive model of human monosaccharide transport, signalling and metabolism. The resulting quantitative model comprising a kinetic model describing monosaccharide transport and insulin signalling integrated with a hepatocyte-specific genome-scale metabolic network (GSMN). Differential kinetics for the utilisation of glucose and fructose were predicted, but the resultant triacylglycerol production was predicted to be similar for monosaccharides; these predictions were verified by in vitro data. The role of physiological adaptation to lipid overload was explored through the comprehensive reconstruction of the peroxisome proliferator activated receptor alpha (PPARα) regulome integrated with a hepatocyte-specific GSMN. The resulting qualitative model reproduced metabolic responses to increased fatty acid levels and mimicked lipid loading in vitro. The model predicted that activation of PPARα by lipids produces a biphasic response, which initially exacerbates steatosis. Our data support the evidence that it is the quantity of sugar rather than the type that is critical in driving the steatotic response. Furthermore, we predict PPARα-mediated adaptations to hepatic lipid overload, shedding light on potential challenges for the use of PPARα agonists to treat NAFLD.

Proteomic identification and characterization of hepatic glyoxalase 1 dysregulation in non-alcoholic fatty liver disease

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common liver disease worldwide. However, its molecular pathogenesis is incompletely characterized and clinical biomarkers remain scarce. The aims of these experiments were to identify and characterize liver protein alterations in an animal model of early, diet-related, liver injury and to assess novel candidate biomarkers in NAFLD patients.

Methods

Liver membrane and cytosolic protein fractions from high fat fed apolipoprotein E knockout (ApoE^−/−) animals were analyzed by quantitative proteomics, utilizing isobaric tags for relative and absolute quantitation (iTRAQ) combined with nano-liquid chromatography and tandem mass spectrometry (nLC-MS/MS). Differential protein expression was confirmed independently by immunoblotting and immunohistochemistry in both murine tissue and biopsies from paediatric NAFLD patients. Candidate biomarkers were analyzed by enzyme-linked immunosorbent assay in serum from adult NAFLD patients.

Results

Through proteomic profiling, we identified decreased expression of hepatic glyoxalase 1 (GLO1) in a murine model. GLO1 protein expression was also found altered in tissue biopsies from paediatric NAFLD patients. In vitro experiments demonstrated that, in response to lipid loading in hepatocytes, GLO1 is first hyperacetylated then ubiquitinated and degraded, leading to an increase in reactive methylglyoxal. In a cohort of 59 biopsy-confirmed adult NAFLD patients, increased serum levels of the primary methylglyoxal-derived advanced glycation endproduct, hydroimidazolone (MG-H1) were significantly correlated with body mass index (r = 0.520, p < 0.0001).

Conclusion

Collectively these results demonstrate the dysregulation of GLO1 in NAFLD and implicate the acetylation-ubquitination degradation pathway as the functional mechanism. Further investigation of the role of GLO1 in the molecular pathogenesis of NAFLD is warranted.

Electronic supplementary material

The online version of this article (10.1186/s12953-018-0131-y) contains supplementary material, which is available to authorized users.

Physical activity and family-based obesity treatment: a review of expert recommendations on physical activity in youth

Targeting physical inactivity in children is pertinent to aiding in the decrease of childhood obesity rates. Only 33% of adolescents are obtaining the recommended goal of at least 60 min of physical activity per day. The objectives of this review are to summarize professional recommendations for physical activity and exercise in children and adolescents, and identify family-centred strategies that can be implemented by weight management clinicians. Clinically oriented recommendations and policy statements from professional organizations were identified through literature and internet searches, summarized using rubrics of aerobic, muscle strengthening and bone strengthening exercise, then examined for details on family-based focus, inclusion of child developmental stage and age, and application to the prevention and treatment of obesity. Current recommendations give guidelines for the amount of physical activity that children should acquire and how many days a week activities should occur. However, available guidelines need an improved approach to addressing the role of the parents and caregivers in targeting physical activity and weight management in youth. Efforts must be taken in order to make sure that the types of physical activity offered are both suitable and enjoyable. Sports, games, free play and other age appropriate activities are adequate ways to increase moderate to vigorous physical activity in children. Differentiating physical activities types in accordance with developmental stage, level of enjoyment, and family characteristics is needed to establish sustainable habits. One paediatric obesity program has developed approaches to teaching families fun and engaging ways to be active together.

Integration of Genome Scale Metabolic Networks and Gene Regulation of Metabolic Enzymes With Physiologically Based Pharmacokinetics

The scope of physiologically based pharmacokinetic (PBPK) modeling can be expanded by assimilation of the mechanistic models of intracellular processes from systems biology field. The genome scale metabolic networks (GSMNs) represent a whole set of metabolic enzymes expressed in human tissues. Dynamic models of the gene regulation of key drug metabolism enzymes are available. Here, we introduce GSMNs and review ongoing work on integration of PBPK, GSMNs, and metabolic gene regulation. We demonstrate example models.

Systematic Review: Nutrition and Physical Activity in the Management of Paediatric Nonalcoholic Fatty Liver Disease

OBJECTIVES

The aim of the study was to evaluate efficacy of nutrition and physical activity interventions in the clinical management of paediatric nonalcoholic fatty liver disease. The prevalence of paediatric nonalcoholic fatty liver disease continues to rise alongside childhood obesity. Weight loss through lifestyle modification is currently first-line treatment, although supplementation of specific dietary components may be beneficial.

METHODS

Medline, CINAHL, EMBASE, Scopus, and Cochrane Libraries were systematically searched to identify randomized controlled trials assessing nutritional and physical activity interventions. Primary outcome measures were changes to liver biomarkers assessed by imaging, histology, or serum liver function tests. Study quality was evaluated using the American Dietetic Association Quality Criteria Checklist.

RESULTS

Fifteen articles met eligibility criteria investigating nutritional supplementation (vitamin E [n = 6], probiotics [n = 2], omega-3 fatty acids [n = 5]), dietary modification (low glycaemic load [n = 1] and reducing fructose intake [n = 1]). No randomized controlled trials examining physical activity interventions were identified. Vitamin E was ineffective at improving alanine transaminase levels, whereas omega-3 fatty acids decreased hepatic fat content. Probiotics gave mixed results, whereas reduced fructose consumption did not improve primary outcome measures. A low glycaemic load diet and a low-fat diet appeared equally effective in decreasing hepatic fat content and transaminases. Most studies were deemed neutral as assessed by the American Dietetic Association Quality Criteria Checklist.

CONCLUSIONS

The limited evidence base inhibits the prescription of specific dietary and/or lifestyle strategies for clinical practice. General healthy eating and physical activity guidelines, promoting weight loss, should remain first-line treatment until high-quality evidence emerges that support specific interventions that offer additional clinical benefit.

Efficacy of dietary and physical activity intervention in non-alcoholic fatty liver disease: a systematic review

Background

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease worldwide, with prevalence above 30% in many adult populations. Strongly associated with obesity, weight loss through diet and physical activity is the mainstay of its management. Weight loss can be difficult to achieve and maintain however, and uncertainty exists as to which lifestyle changes are most effective.

Objective

The aim of this work was to systematically evaluate randomised controlled trials assessing diet, exercise or combination interventions aimed at reducing steatosis or markers of NAFLD activity.

Design

Medline, Scopus and Cochrane databases were searched from 1 January 1980 through to 31 July 2016, for intervention trials assessing the effects of diet, weight loss, exercise or any combination thereof, on NAFLD disease markers in human adults. Risk of publication bias and study quality was assessed using the American Dietetic Association Quality Criteria Checklist.

Results

From a total of 1710 identified records, 24 articles met the inclusion and exclusion criteria; 6 assessed weight loss using dietary restriction, 10 assessed exercise and 8 were combination interventions. While all of the trials demonstrated significant reduction in steatosis and/or markers of NAFLD activity, combination interventions appear to be the most effective at improving NAFLD. Results suggest that 5–10% weight loss using a modestly hypocaloric diet of 500 kcal less per day than calculated energy requirement, in combination with 30–60 min exercise on 3–5 days per week should be recommended.

Conclusions

We conclude this amount of weight loss is achievable in the trial setting but is challenging in the clinical environment. High-intensity, multidisciplinary intervention in specialist clinics is likely to be required in order to manage NAFLD by lifestyle modification alone. This systematic review protocol was registered prospectively at PROSPERO as CRD42016032764.

Sugar and metabolic health: is there still a debate?

PURPOSE OF REVIEW

There is considerable political and public awareness of new recommendations to reduce sugars and sugar-sweetened beverages in our diets. It is therefore timely to review the most recent changes in guidelines, with a focus on evidence for metabolic health, recent research in the area and gaps in our knowledge.

RECENT FINDINGS

Sufficient evidence links a high intake of sugar to dental caries and obesity, and high intakes of sugar-sweetened beverages in particular to increased risk of type 2 diabetes. This has led to the updating of dietary recommendations related to added sugars in the diet. The effects of specific sugars at usual intakes as part of an isoenergetic diet are less clear. The glycaemic response to food is complex and mediated by many factors, but sugar intake is not necessarily the major component.

SUMMARY

There are many challenges faced by healthcare professionals and government bodies in order to improve the health of individuals and nations through evidence-based diets. Sufficiently powered long-term mechanistic studies are still required to provide evidence for the effects of reducing dietary sugars on metabolic health. However, there are many challenges for research scientists in the implementation of these studies.

Sample Preparation Approaches for iTRAQ Labeling and Quantitative Proteomic Analyses in Systems Biology

Among a variety of global quantification strategies utilized in mass spectrometry (MS)-based proteomics, isobaric tags for relative and absolute quantitation (iTRAQ) are an attractive option for examining the relative amounts of proteins in different samples. The inherent complexity of mammalian proteomes and the diversity of protein physicochemical properties mean that complete proteome coverage is still unlikely from a single analytical method. Numerous options exist for reducing protein sample complexity and resolving digested peptides prior to MS analysis. Indeed, the reliability and efficiency of protein identification and quantitation from an iTRAQ workflow strongly depend on sample preparation upstream of MS. Here we describe our methods for: (1) total protein extraction from immortalized cells; (2) subcellular fractionation of murine tissue; (3) protein sample desalting, digestion, and iTRAQ labeling; (4) peptide separation by strong cation-exchange high-performance liquid chromatography; and (5) peptide separation by isoelectric focusing.

Assessment of Diet and Physical Activity in Paediatric Non-Alcoholic Fatty Liver Disease Patients: A United Kingdom Case Control Study

Non-alcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease in children, with prevalence rising alongside childhood obesity rates. This study aimed to characterise the habitual diet and activity behaviours of children with NAFLD compared to obese children without liver disease in the United Kingdom (UK). Twenty-four biopsy-proven paediatric NAFLD cases and eight obese controls without biochemical or radiological evidence of NAFLD completed a 24-h dietary recall, a Physical Activity Questionnaire (PAQ), a Dutch Eating Behavior Questionnaire (DEBQ) and a 7-day food and activity diary (FAD), in conjunction with wearing a pedometer. Groups were well matched for age and gender. Obese children had higher BMI z-scores (p = 0.006) and BMI centiles (p = 0.002) than participants with NAFLD. After adjusting for multiple hypotheses testing and controlling for differences in BMI, no differences in macro- or micronutrient intake were observed as assessed using either 24-h recall or 7-day FAD (p > 0.001). Under-reporting was prevalent (NAFLD 75%, Obese Control 87%: p = 0.15). Restrained eating behaviours were significantly higher in the NAFLD group (p = 0.005), who also recorded more steps per day than the obese controls (p = 0.01). In conclusion, this is the first study to assess dietary and activity patterns in a UK paediatric NAFLD population. Only a minority of cases and controls were meeting current dietary and physical activity recommendations. Our findings do not support development of specific dietary/ physical activity guidelines for children with NAFLD; promoting adherence with current general paediatric recommendations for health should remain the focus of clinical management.

The effect of supplementation with alkaline potassium salts on bone metabolism: a meta-analysis

The role of acid-base metabolism in bone health is controversial. In this meta-analysis, potassium bicarbonate and potassium citrate lowered urinary calcium and acid excretion and reduced the excretion of the bone resorption marker NTX. These salts may thus be beneficial to bone health by conserving bone mineral.

INTRODUCTION

The role of acid-base homeostasis as a determinant of bone health and the contribution of supplemental alkali in promoting skeletal integrity remain a subject of debate. The objective of this study was, therefore, to conduct a meta-analysis to assess the effects of supplemental potassium bicarbonate (KHCO3) and potassium citrate (KCitr) on urinary calcium and acid excretion, markers of bone turnover and bone mineral density (BMD) and to compare their effects with that of potassium chloride (KCl).

METHODS

A total of 14 studies of the effect of alkaline potassium salts on calcium metabolism and bone health, identified by a systematic literature search, were analysed with Review Manager (Version 5; The Cochrane Collaboration) using a random-effects model. Authors were contacted to provide missing data as required. Results are presented as the standardised (SMD) or unstandardized mean difference (MD) (95 % confidence intervals).

RESULTS

Urinary calcium excretion was lowered by intervention with both KHCO3 (P = 0.04) and KCitr (P = 0.01), as was net acid excretion (NAE) (P = 0.002 for KHCO3 and P = 0.0008 for KCitr). Both salts significantly lowered the bone resorption marker NTX (P < 0.00001). There was no effect on bone formation markers or BMD. KHCO3 and KCitr lowered calcium excretion to a greater extent than did KCl.

CONCLUSIONS

This meta-analysis confirms that supplementation with alkaline potassium salts leads to significant reduction in renal calcium excretion and acid excretion, compatible with the concept of increased buffering of hydrogen ions by raised circulating bicarbonate. The observed reduction in bone resorption indicates a potential benefit to bone health.

The role of dietary sugars and de novo lipogenesis in non-alcoholic fatty liver disease

Dietary sugar consumption, in particular sugar-sweetened beverages and the monosaccharide fructose, has been linked to the incidence and severity of non-alcoholic fatty liver disease (NAFLD). Intervention studies in both animals and humans have shown large doses of fructose to be particularly lipogenic. While fructose does stimulate de novo lipogenesis (DNL), stable isotope tracer studies in humans demonstrate quantitatively that the lipogenic effect of fructose is not mediated exclusively by its provision of excess substrates for DNL. The deleterious metabolic effects of high fructose loads appear to be a consequence of altered transcriptional regulatory networks impacting intracellular macronutrient metabolism and altering signaling and inflammatory processes. Uric acid generated by fructose metabolism may also contribute to or exacerbate these effects. Here we review data from human and animal intervention and stable isotope tracer studies relevant to the role of dietary sugars on NAFLD development and progression, in the context of typical sugar consumption patterns and dietary recommendations worldwide. We conclude that the use of hypercaloric, supra-physiological doses in intervention trials has been a major confounding factor and whether or not dietary sugars, including fructose, at typically consumed population levels, effect hepatic lipogenesis and NAFLD pathogenesis in humans independently of excess energy remains unresolved.