Association of proinflammatory diet with low-grade inflammation: results from the Moli-sani study

Dietary inflammatory index and number of functional teeth in middle-aged and older Japanese adults: A cross-sectional study using national survey data

PURPOSE

To determine whether the number of functional teeth, including the remaining natural teeth and prosthetically restored missing teeth, is associated with the dietary inflammatory index (DII), a quantitative measure of the inflammatory potential of the overall diet, in middle-aged and older Japanese adults.

METHODS

National survey data from a non-institutionalized Japanese population aged ≥45 years was analyzed. Multivariable linear regression analyses were performed to assess the association between the DII score, which was calculated based on dietary records, and the number of functional teeth, which was determined during dental examination. All regression analyses were stratified according to the age groups 45-64, 65-74, and ≥75 years. The association between functional tooth units (FTUs) and the DII was assessed using sensitivity analysis.

RESULTS

In total, 2407 individuals (1053 men and 1354 women; mean age = 66.7 years) were included. Multivariable analysis revealed that the number of functional teeth was significantly inversely associated with the DII score among participants aged ≥75 years (regression coefficient per increase of one in the number of functional teeth = -0.050; 95% confidence interval = -0.089 to -0.010). The number of functional teeth was not associated with the DII score in younger age categories (i.e., those aged 45-74 years). As in the primary analysis, the number of FTUs was significantly inversely associated with the DII score only in the group aged ≥75 years.

CONCLUSIONS

A greater number of functional teeth was associated with a lower DII (i.e., diet with greater anti-inflammatory potential) in Japanese adults aged ≥75 years.

Chronic low-grade inflammation associated with higher risk and earlier onset of cardiometabolic multimorbidity in middle-aged and older adults: a population-based cohort study

Evidence regarding the role of chronic low-grade inflammation in the progression of cardiometabolic diseases (CMDs) and cardiometabolic multimorbidity (CMM) is currently limited. This prospective cohort study, utilising data from the UK Biobank, included 273,804 adults aged 40-69 years initially free of CMD at baseline. CMM was defined as the coexistence of two or more CMDs, such as coronary artery disease, type 2 diabetes mellitus, hypertension and stroke. The aggregated inflammation score (INFLA-score), incorporating C-reactive protein, white blood cell count, platelet count and granulocyte-to-lymphocyte ratio, quantified chronic low-grade inflammation. Absolute risks (ARs), hazard ratios (HRs) and 95% confidence intervals (CIs) assessed the association of increased INFLA-score with the risk of CMMs and CMDs. The accelerated failure time model explored the effect of INFLA-score on the time to CMM onset, and a restricted cubic spline characterised the dose-dependent relationship between INFLA-score and CMM risk. After a median follow-up of 166.37 months, 13,755 cases of CMM were identified. In quartiles with increasing INFLA-score levels, CMM ARs were 4.41%, 4.49%, 5.04% and 6.01%, respectively; HR increased by 2%, 15% and 36%, respectively, compared to the lowest quartile. The INFLA-score and CMM risk relationship was nonlinear (P for nonlinear < 0.001), exhibiting a significant risk trend change at a score of 9. For INFLA-score < 9, CMM risk increased by 1.9% for each 1-point increase; for INFLA-score ≥ 9, the risk increased by 5.9% for each 1-point increase. Additionally, a higher INFLA-score was associated with an earlier onset of CMM (P < 0.001). Compared to the first INFLA-score quartile, the AFT model revealed adjusted median times to CMM occurrence were 2.92, 6.10 and 13.19 months earlier in the second, third and fourth quartile groups, respectively. Chronic low-grade inflammation is associated with a higher risk of cardiometabolic multimorbidity and earlier onset among middle-aged and older adults. Monitoring and screening the INFLA-score in adults without CMDs may improve early prevention of CMM.

Impact of dietary inflammatory index on gestational diabetes mellitus in normal and overweight women: a systematic review and meta-analysis of observational studies

BACKGROUND AND OBJECTIVES

To systematically investigate the association between the dietary inflammatory index (DII) and gestational diabetes mellitus (GDM), with a focus on the role of BMI in this relationship.

METHODS AND STUDY DESIGN

A comprehensive search was conducted in PubMed, Embase, Web of Science, The Cochrane Library, Medline, CINAHL Complete, Chinese Periodical Full-text Database, China National Knowledge Infrastructure, Chinese Biomedical Literature Database, and China Wanfang Database for rele-vant observational studies published up to August 2023. The quality of the included studies was assessed using the Newcastle-Ottawa Scale. The pooled effect size was calculated using a random-effects model. Sub-group and meta-regression analyses were performed to explore potential sources of heterogeneity.

RESULTS

The study included 54,058 participants from 10 studies. Pregnant women with a higher DII, indicating a pro-inflammatory diet, had a significantly increased risk of GDM compared to those with a lower DII, indicating an anti-inflammatory diet (pooled OR: 1.17, 95% CI: 1.01-1.36; I²=70%, p <0.001). Subgroup analyses revealed a stronger association in normal weight stratification (OR: 1.25, 95%CI: 1.04-1.51), case-control studies (OR: 1.45, 95%CI: 1.03-2.05), Asia (OR: 1.26, 95%CI: 1.10-1.43), Europe (OR: 1.27, 95%CI: 1.09-1.48), 3-day dietary record as a dietary assessment tool (OR: 1.30, 95%CI: 1.16-1.46), physical activity adjustment (OR: 1.28, 95%CI: 1.13-1.46), and energy intake adjustment (OR: 1.33, 95%CI: 1.19-1.48). Meta-regression analysis confirmed that geographical region significantly influenced heterogeneity between studies (p <0.05).

CONCLUSIONS

An elevated DII is independently linked to a higher risk of GDM, especially in women of normal weight.

Chronic Low-Grade Inflammation and Brain Structure in the Middle-Aged and Elderly Adults

Low-grade inflammation (LGI) mainly acted as the mediator of the association of obesity and inflammatory diet with numerous chronic diseases, including neuropsychiatric diseases. However, the evidence about the effect of LGI on brain structure is limited but important, especially in the context of accelerating aging. This study was then designed to close the gap, and we leveraged a total of 37,699 participants from the UK Biobank and utilized inflammation score (INFLA-score) to measure LGI. We built the longitudinal relationships of INFLA-score with brain imaging phenotypes using multiple linear regression models. We further analyzed the interactive effects of specific covariates. The results showed high level inflammation reduced the volumes of the subcortex and cortex, especially the globus pallidus (β [95% confidence interval] = -0.062 [-0.083, -0.041]), thalamus (-0.053 [-0.073, -0.033]), insula (-0.052 [-0.072, -0.032]), superior temporal gyrus (-0.049 [-0.069, -0.028]), lateral orbitofrontal cortex (-0.047 [-0.068, -0.027]), and others. Most significant effects were observed among urban residents. Furthermore, males and individuals with physical frailty were susceptive to the associations. The study provided potential insights into pathological changes during disease progression and might aid in the development of preventive and control targets in an age-friendly city to promote great health and well-being for sustainable development goals.

Dietary Inflammatory Index and Cognitive Function: Findings from a Cross-Sectional Study in Obese Chinese Township Population from 45 to 75 Years

Background and Objective

Cognitive dysfunction is highly prevalent in obese people, and food is a key factor in obesity, and dietary inflammatory index (DII) can reflect whether diet has anti-inflammatory or pro-inflammatory potential. In addition, dietary fatty acid consumption is linked to inflammation, obesity, and cognitive impairment. Erythrocyte membrane fatty acids can reflect dietary fatty acid intake. Our hypothesis was that erythrocyte membrane fatty acids might have a significant impact on the relationship between DII and cognition in obese individuals, and we designed experiments to test the hypothesis.

Methods

In three villages in Beijing, we collected 579 respondents from individuals 45 to 75 years old and categorized them by body mass index. The Montreal Cognitive Assessment (MoCA) score and DII score was calculated and gas chromatography was used to measure the proportion of erythrocyte membrane fatty acids. The relationship between the DII score and cognition was examined using multiple linear regression and binary logistic regression. Mediation analysis can help to understand the causal chain between variables, deeply explore the internal relationship and mechanism of action between variables. So a multiple chain mediation model was developed to investigate the mediating factors between the DII score and cognitive association.

Results

According to adjusted linear regression, higher DII scores were linked to lower MoCA scores in the obese group. The negative correlation between DII score and cognitive function score remains in binary linear regression. We discovered through mediation analysis that erythrocyte membrane fatty acids mediate the detrimental link between DII and cognitive function in obese individuals.

Conclusion

We propose that higher DII scores in obese people are associated with a decline in cognitive function. In addition, this effect might be mediated via the fatty acids in the erythrocyte membrane.

Correlation research demonstrates that an inflammatory diet is a risk factor for calcium oxalate renal stone formation

BACKGROUND AND AIMS

Previous studies have demonstrated associations between the Dietary Inflammatory Index (DII®), an analytical tool which evaluates the inflammatory potential of the diet according to the pro- and anti-inflammatory properties of its components, and renal stone formation. However, these have not comprehensively addressed important parameters such as stone type, gender, DII scores in stone formers (SFs) and healthy controls (Cs) and associations of DII with urine and blood chemistries. These were adopted as the survey parameters for the present study, the purpose of which was to test whether the contributory role of an inflammatory diet on stone formation could be further confirmed.

METHODS

97 calcium oxalate (CaOx) SFs and 63 Cs, matched for age and gender each completed a semi-quantitative food frequency questionnaire from which nutrient composition was computed. These data were used to calculate the DII® score. To control the effect of energy intake, energy-adjusted DII scores were calculated per 1000 kcal consumed (E-DII™). A single blood sample and two consecutive overnight (8h) urine samples were collected from a subset (n = 59 SFs and n = 54 Cs) of the overall number of particpants (n = 160). These were analysed for renal stone risk factors. Data were analysed using regression models fit in R software.

RESULTS

E-DII scores were found to fit the data better than DII, so they were used throughout. E-DII scores were significantly more positive (more pro-inflammatory) in SFs than in controls in the combined gender group (-0.34 vs. -1.73, p < 0.0001) and separately in males (-0.43 vs. -1.78, p = 0.01) and females (-0.26 vs. - 1.61, p = 0.05). In blood, a significant negative correlation was seen between E-DII and HDL cholesterol. In urine significant positive correlations were seen between E-DII and each of calcium (ρ = 0.25, p = 0.02), phosphate (ρ = 0.48, p < 0.001), magnesium (ρ = 0.33, p < 0.0001) and uric acid (ρ = 0.27, p = 0.004) concentrations. A significant negative correlation was seen between E-DII and urinary volume ρ = -0.27, p = 0.003). There was no correlation between E-DII scores and the relative supersaturations of urinary CaOx, calcium phosphate (brushite) and uric acid.

CONCLUSIONS

Our findings provide hitherto unreported quantitative evidence in support of the notion that the diet of calcium oxalate renal stone patients is significantly more pro-inflammatory than that of healthy controls.

Geographic disparities of dietary inflammatory index and its association with hypertension in middle-aged and elders in China: results from a nationwide cross-sectional study

Background

Geographic distribution of dietary inflammatory index (DII) in China has not been thoroughly evaluated and evidence on the association between DII and hypertension among Chinese middle-aged and older population was inadequate.

Objective

To investigate the geographic disparities of DII and its association with hypertension among Chinese middle-aged and elders.

Methods

Data was from the China Adults Chronic Diseases and Nutrition Surveillance (CACDNS 2015) for middle-aged and older participants. The DII for each participant was determined through a combination of 3 days 24 h dietary recall interviews and a food frequency questionnaire. Spatial analysis was employed to investigate the geographic distribution of DII in China. Restricted cubic spline models and binary logistic regression analysis were used to assess the relationship between DII and hypertension. The least absolute shrinkage and selection operator (LASSO) regression was applied for identifying key hypertension-related factors, which was then included in the establishment of a risk prediction nomogram model, with the receiver operating characteristic (ROC) curve and decision curve analysis (DCA) being built to evaluate its discriminatory power for hypertension.

Results

A total of 52,087 middle-aged and older participants were included in the study, among whom 36.6% had hypertension. it revealed that a clear spatial correlation in the national distribution of DII scores (Moran I: 0.252, p = 0.001), with higher DII scores concentrated in the northwest region and lower DII scores concentrated in the southeast region. Hypertensive participants had higher DII scores compared to those without hypertension (OR: 1.507 vs. 1.447, p = 0.003). Restricted cubic spline models and binary logistic regression analysis demonstrated a positive association between DII and hypertension after adjusting for potential confounding factors. There was a significant increasing trend in the proportion of hypertensive individuals as DII scores increase (p for trend = 0.004). The nomogram model, constructed using key factors identified through LASSO regression, demonstrated a robust discriminative capacity, with an area under the curve (AUC) of 73.2% (95% CI, 72.4-74.0%). Decision curve analysis confirmed the reliability and effectiveness of the nomogram model. Sensitivity analysis conducted within the subpopulation aged under 45 years yielded results consistent with the primary analysis.

Conclusion

In Chinese adults middle-aged and older, geographic disparities in dietary inflammatory potential are notable, with lower levels observed in the southeastern coastal regions of China and higher levels in the northwestern regions. Meanwhile, there is a positive association between the inflammatory potential of the diet and hypertension. Additional research is needed to investigate regional disparities in dietary inflammatory potential and pinpoint specific dietary patterns associated with lower inflammation.

Dietary Patterns and Risk of Inflammatory Bowel Disease: A Systematic Review of Observational Studies

BACKGROUND

The incidence of inflammatory bowel disease (IBD) is increasing worldwide. Dietary patterns may be associated with odds of this disease. Although previous reviews have attempted to summarize the evidence in this field, the growing body of investigations prompted us to conduct an updated comprehensive systematic review.

METHODS

We used the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to evaluate the association between dietary patterns before disease onset and the risk of IBD. PubMed, SCOPUS, and Web of Science were searched using structured keywords up to November 20, 2023.

RESULTS

Twenty-four publications (13 case-control, 1 nested case-control, and 10 cohort studies) were included in this review. The sample size of these studies ranged from 181 to 482 887 subjects. The findings were inconsistent across the included studies, showing inverse, direct, or no association between different dietary patterns and the risk of IBD.

CONCLUSIONS

This review provides comprehensive data on the link between dietary patterns prior to IBD diagnosis and risk of this condition. The explicit finding of present review is the extent gap in our knowledge in this field. Therefore, large-scale, high-quality studies are warranted to improve our understanding of the relationship between dietary patterns and IBD risk.

Dietary inflammatory index and elevated serum C-reactive protein: A systematic review and meta-analysis

Diet can affect the inflammatory state of the body. Accordingly, the dietary inflammatory index (DII) has been developed to quantify the inflammatory properties of food items. This study sought to investigate the association between dietary inflammation index (DII) and the odds ratio of elevated CRP (E-CRP) through a systematic review and meta-analysis study. The International electronic databases of PubMed, Web of Science (ISI), and Scopus were searched until May 2023 to find related articles. From 719 studies found in the initial search, 14 studies, with a total sample size of 59,941 individuals, were included in the meta-analysis. The calculated pooled odds ratio (OR) of E-CRP in the highest DII category was 1.39 (95% CI: 1.06, 1.14, test for heterogeneity: p = .63, and I 2 = .0%) in comparison with the lowest DII category. Also, the results of this study showed that each unit increase in DII as a continuous variable generally elicited a 10% increase in the odds of E-CRP (OR 1.10, 95% CI 1.06, 1.14, test for heterogeneity: p = .63, and I 2 = .0%). Subgroup meta-analyses showed that there is a higher E-CRP odds ratio for the articles that reported energy-adjusted DII (E-DII) instead of DII, the studies that measured CRP instead of hs-CRP, and the studies that used 24-h recall instead of FFQ as the instrument of dietary intake data collection. Individuals with a higher DII were estimated to have higher chances of developing elevated serum CRP. This value was influenced by factors such as the participants' nationality, instruments of data collection, methods used to measure inflammatory biomarkers, study design, and data adjustments. However, future well-designed studies can help provide a more comprehensive understanding of the inflammatory properties of diet and inflammatory serum biomarkers.

Associations between dietary inflammatory scores and biomarkers of inflammation in the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

BACKGROUND

Since the first version of the dietary inflammatory index (DII®) developed in the past decade, several other versions have been developed. However, to date no study has attempted to compare these versions with respect to their associations with biomarkers of inflammation.

OBJECTIVE

We aimed to investigate the relationship between four dietary inflammatory scores [DII, two energy-adjusted derivatives (E-DII and E-DIIr), and the Inflammatory Score of the Diet (ISD)], and circulating levels of several inflammatory markers and adipokines.

METHODS

This study included 17 637 participants from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort with at least one marker of inflammation measured in blood. Associations between the four scores and C-reactive protein (CRP), interleukin (IL)6, IL10, IL1RA, tumor necrosis factor-α (TNFα), soluble tumor necrosis factor receptor-1 (sTNFR1), sTNFR2, leptin, soluble leptin receptor (sLeptin R), adiponectin, and High Molecular Weight (HMW) adiponectin were evaluated using multivariable linear regressions adjusted for potential confounders.

RESULTS

Positive associations were observed between the four dietary inflammatory scores and levels of CRP, IL6, sTNFR1, sTNFR2 and leptin. However, only the DII and the ISD were positively associated with IL1RA levels and only the DII and the E-DIIr were positively associated with TNFα levels. The proportion of variance of each biomarker explained by the scores was lower than 2%, which was equivalent to the variance explained by smoking status but much lower than that explained by body mass index.

CONCLUSIONS

Our results suggest that the four dietary inflammatory scores were associated with some biomarkers of inflammation and could be used to assess the inflammatory potential of diet in European adults but are not sufficient to capture the inflammatory status of an individual. These findings can help to better understand the inflammatory potential of diet, but they need to be replicated in studies with repeated dietary measurements.

Association between the Inflammatory Potential of the Diet and Biological Aging: A Cross-Sectional Analysis of 4510 Adults from the Moli-Sani Study Cohort

Chronological age (CA) may not accurately reflect the health status of an individual. Rather, biological age (BA) or hypothetical underlying "functional" age has been proposed as a relevant indicator of healthy aging. Observational studies have found that decelerated biological aging or Δage (BA-CA) is associated with a lower risk of disease and mortality. In general, CA is associated with low-grade inflammation, a condition linked to the risk of the incidence of disease and overall cause-specific mortality, and is modulated by diet. To address the hypothesis that diet-related inflammation is associated with Δage, a cross-sectional analysis of data from a sub-cohort from the Moli-sani Study (2005-2010, Italy) was performed. The inflammatory potential of the diet was measured using the Energy-adjusted Dietary Inflammatory Index (E-DII^TM) and a novel literature-based dietary inflammation score (DIS). A deep neural network approach based on circulating biomarkers was used to compute BA, and the resulting Δage was fit as the dependent variable. In 4510 participants (men 52.0%), the mean of CA (SD) was 55.6 y (±11.6), BA 54.8 y (±8.6), and Δage -0.77 (±7.7). In a multivariable-adjusted analysis, an increase in E-DII^TM and DIS scores led to an increase in Δage (β = 0.22; 95%CI 0.05, 0.38; β = 0.27; 95%CI 0.10, 0.44, respectively). We found interaction for DIS by sex and for E-DII^TM by BMI. In conclusion, a pro-inflammatory diet is associated with accelerated biological aging, which likely leads to an increased long-term risk of inflammation-related diseases and mortality.

The Mediating Effect of Central Obesity on the Association between Dietary Quality, Dietary Inflammation Level and Low-Grade Inflammation-Related Serum Inflammatory Markers in Adults

To date, few studies have explored the role of central obesity on the association between diet quality, measured by the health eating index (HEI), inflammatory eating index (DII), and low-grade inflammation-related serum inflammatory markers. In this paper, we use the data from the 2015-2018 National Health and Nutrition Examination Survey (NHANES) to explore this. Dietary intakes were measured during two 24-h dietary recall interviews and using USDA Food Pattern Equivalence Database (FPED) dietary data. Serum inflammatory markers were obtained from NHANES Laboratory Data. Generalized structural equation models (GSEMs) were used to explore the mediating relationship. Central obesity plays a significant mediating role in the association between HEI-2015 and high-sensitivity C-reactive protein (hs-CRP), mediating 26.87% of the associations between the two; it also mediates 15.24% of the associations between DII and hs-CRP. Central obesity plays a mediating role in 13.98% of the associations between HEI-2015 and white blood cells (WBC); it also mediates 10.83% of the associations between DII and WBC. Our study suggests that central obesity plays a mediating role in the association of dietary quality with low-grade inflammation-related serum inflammatory markers (hs-CRP and WBC).

Higher Dietary Inflammatory Index scores are associated with brain MRI markers of brain aging: Results from the Framingham Heart Study Offspring cohort

INTRODUCTION

We investigated cross-sectional associations between the Dietary Inflammatory Index (DII) and measures of brain volume and cerebral small vessel disease among participants of the Framingham Heart Study Offspring cohort.

METHODS

A total of 1897 participants (mean ± standard deviation, age 62±9) completed Food Frequency Questionnaires and brain magnetic resonance imaging (MRI).

RESULTS

Higher (pro-inflammatory) DII scores, averaged across a maximum of three time points, were associated with smaller total brain volume (beta ± standard error: -0.16 ± 0.03; P < .0001) after adjustment for demographic, clinical, and lifestyle covariates. In addition, higher DII scores were associated with smaller total gray matter volume (-0.08 ± 0.03; P = .003) and larger lateral ventricular volume (0.04 ± 0.02; P = .03). No associations were observed with other brain MRI measures.

DISCUSSION

Our findings showed associations between higher DII scores and global brain MRI measures. As we are one of the first groups to report on the associations between higher DII scores and brain volume, replication is needed to confirm our findings.

Comparison of Intake of Food Groups Based on Dietary Inflammatory Index (DII) and Cardiovascular Risk Factors in the Middle-Age Population of Lower Silesia: Results of the PURE Poland Study

Chronic inflammation is involved in the pathogenesis of many non-infectious diseases, including cardiovascular diseases (CVD), a leading cause of death in Europe. The aim of the study was to assess the inflammatory potential of the diets of participants enrolled in the Polish arm of the Prospective Urban and Rural Epidemiological (PURE) study, evaluate the association between the dietary inflammatory index (DII) score with the dietary content, and to determine the correlation of DII score with selected anthropometric parameters and biochemical risk factors for CVD. Diets were assessed with the Food Frequency Questionnaire (FFQ). Among participants with pro-inflammatory diets, we reported higher mean values of triglycerides (TG), fasting glucose (FG), atherogenic index of plasma (AIP), and the Castelli's risk index (CRI) in the group of men and women, and higher waist circumference (WC) and waist-to-hip ratio (WHR) in the group of women. Pro-inflammatory diets were associated with higher intake of refined grains, sweets, juices, red meat, high-fat cheese and cream, alcohol, fats except for vegetable oils, potatoes, sugar and honey, French fries, fried fish, and processed/high-fat poultry. Moreover, study participants with pro-inflammatory diets consumed more milk, low-fat dairy, and eggs associated with unhealthy dietary habits, but this should not be considered as an independent CVD risk factor. Anthropometric and biochemical outcomes were more favorable among study participants who consumed more vegetables, fruits, nuts, seeds, raisins, pulses, low-fat poultry, and tea. However, association of beverage consumption with dietary inflammatory potential requires further study.

Adherence to a Mediterranean Diet for 6 Months Improves the Dietary Inflammatory Index in a Western Population: Results from the MedLey Study

Increasing evidence supports that a higher dietary inflammatory index (DII®) score is associated with inflammation and cardiovascular disease (CVD) risk, events, and mortality. This randomized trial sought to determine if a change to a Mediterranean diet resulted in a reduction in the DII score, and then it evaluated the relationship between the DII and cardiometabolic outcomes following the administration of a traditional Mediterranean diet in older Australian adults. A total of 152 Australian adults (mean age 71 ± 5 years) was randomly allocated either a MedDiet (n = 80) or to continue their habitual diet (HabDiet) (n = 72) for 6 months. Diet and cardiovascular outcomes were measured at baseline and 3 and 6 months of the intervention. DII and energy-adjusted DII (E-DIITM) scores were calculated from 3-day weighed food records. There was a significant reduction in the DII score at 2 and 4 months for the MedDiet group (−1.40 ± 0.20 p < 0.001 and −1.47 ± 0.20 p < 0.001, respectively), which was significantly different from the HabDiet group over time (p < 0.001). The HabDiet DII score did not change significantly at the 2 and 4 months timepoints (0.47 ± 0.21 p = 0.35 and 0.54 ± 0.21 p = 0.21, respectively). The improvement in the DII in the MedDiet group was not related to any cardiometabolic outcome. Baseline cross-sectional analyses identified a positive association between the E-DII score and average BMI, body weight, WHR, abdominal adiposity, and SBP, and a negative association with HDL-C. We demonstrate that a MedDiet intervention significantly reduced DII scores compared with a habitual Australian diet in older Australians. This could be beneficial for healthy ageing and the avoidance of chronic disease in Western populations.

Association of macronutrients intake distribution with osteoarthritis risk among adults in NHANES, 2013-2016

The association between dietary macronutrient distribution and the risk of OA remains unknown. We aimed to evaluate how dietary macronutrient distribution was correlated with the risk of OA in US adults. We performed a cross-sectional study consisting of 7,725 participants from National Health and Nutrition Examination Survey (NHANES) 2013-2016. Dietary macronutrient intake and OA status were assessed by using dietary recall method and self-reported questionnaire, respectively. We evaluated the association between dietary macronutrient distribution and the risk of OA using multivariate regression models. We conducted the isocaloric substitution analysis using the multivariate nutrient density method. Higher percentage of energy intake from fat was associated with higher risk of OA [OR = 1.05 (95% CI, 1.00, 1.09); P = 0.034]. No significant correlation was observed between the percentage of energy intake from carbohydrate or protein and risk of OA. Isocaloric substitution analysis revealed that only the substitution between fat and carbohydrate was significantly associated with the risk of OA [OR = 1.05 (95% CI, 1.003 to 1.09); P = 0.037]. Our findings suggested that a diet with low percentage of energy intake from fat may be beneficial in the prevention of OA. Further prospective cohort studies are needed to assess our results.

Associations of circulating levels of phthalate metabolites with cytokines and acute phase reactants in a Spanish human cohort

The associations between human phthalate exposure and the onset of chronic diseases with an immunological component (e.g., metabolic syndrome, cancer) remain unclear, partly due to the uncertainties in the underlying mechanisms. This study investigates cross-sectional associations of the concentrations of 10 phthalate metabolites with 19 cytokines and acute phase proteins in 213 serum samples of Spanish adults. The associations were explored by Spearman's correlation, multivariable linear regression, and weighted quantile sum regression analyses. In the multivariable analyses, levels of plasminogen activator inhibitor (PAI)-1 were positively associated with mono-n-butyl phthalate (fold-change per one IQR increase in phthalate levels, 95% Confidence Interval: 1.65, 1.45-1.88) and mono-iso-butyl phthalate (3.07, 2.39-3.95), mono-ethyl phthalate (2.05, 1.62-2.61), as well as categorized mono-iso-decyl and mono-benzyl phthalates. The same phthalates also were significantly associated with leptin, interleukin (IL)-18 and monocyte chemoattractant protein-1. Moreover, the proinflammatory markers IL-1β, IL-17, IL-8, IL-6, IL-12, tumor necrosis factor, and lipopolysaccharide-binding protein showed positive and negative associations with, respectively, mono-(2-ethyl-hexyl) and mono-methyl phthalates. Finally, phthalate mixtures were positively associated with PAI-1, leptin, IL-18, IL-12, IL-8 and IL-1β. Despite the cross-sectional design limitation, these associations point to relevant subclinical immuno-inflammatory actions of these pollutants, warranting confirmation in future studies.

The dietary inflammatory index is associated with aerobic performance and anthropometric measures of marines

Evidence propose that dietary intake affects physical performance and body composition. The present study aimed to determine the relationship between dietary inflammatory index (DII) with physical function and anthropometric indices in the marine. This cross-sectional study was performed on 300 males aged 18 to 45 years serving in the Navy. A general questionnaire was used to collect demographic data of participants. Also, the anthropometric indices (height, weight, waist circumference, and hip circumference) were measured to calculate a body shape index (ABSI), abdominal volume index (AVI), body adiposity index (BAI), and conicity as new anthropometric indices. Moreover, the 12-min Cooper, sit up, pull up, and push up were used to assess physical performance. Food intake over the past year was assessed using a 147-item food frequency questionnaire, and then the DII score was calculated for each subject. Aerobic performance was assessed using the Cooper test. Also, the repetitions of sit up, pull up and push up in 1 minute were recorded to assess muscular endurance. The present study showed that the increase in DII is directly related to body mass index (BMI) (P=0.04), body fat percentage (P=0.03), and BAI (P=0.010) and inversely related to VO2max (P=0.001). However, after adjusting for the effect of energy intake in regression model, only the association between DII and VO2max was statistically significant (β=-1.69, standard error=0.67, P=0.01). The increase in the dietary inflammatory potential is associated to a higher BMI and body adiposity and a lower aerobic capacity in military personnel. However, the observed relationship between DII and anthropometric indices seems to be influenced by the energy intake. Further well-designed studies with a prospective method are warranted.

Unpacking determinants and consequences of food insecurity for insulin resistance among people living with HIV: Conceptual framework and protocol for the NOURISH-OK study

Background:

Over the past four decades, advances in HIV treatment have contributed to a longer life expectancy for people living with HIV (PLWH). With these gains, the prevention and management of chronic co-morbidities, such as diabetes, are now central medical care goals for this population. In the United States, food insecurity disproportionately impacts PLWH and may play a role in the development of insulin resistance through direct and indirect pathways. The Nutrition to Optimize, Understand, and Restore Insulin Sensitivity in HIV for Oklahoma (NOURISH-OK) will use a novel, multi-level, integrated framework to explore how food insecurity contributes to insulin resistance among PLWH. Specifically, it will explore how food insecurity may operate as an intermediary risk factor for insulin resistance, including potential linkages between upstream determinants of health and downstream consequences of poor diet, other behavioral risk factors, and chronic inflammation.

Methods/design:

This paper summarizes the protocol for the first aim of the NOURISH-OK study, which involves purposeful cross-sectional sampling of PLWH (n=500) across four levels of food insecurity to test our conceptual framework. Developed in collaboration with community stakeholders, this initial phase involves the collection of anthropometrics, fasting blood samples, non-blood biomarkers, 24-hour food recall to estimate the Dietary Inflammatory Index (DII^®) score, and survey data. A 1-month, prospective observational sub-study (total n=100; n=25 for each food security group) involves weekly 24-hour food recalls and stool samples to identify temporal associations between food insecurity, diet, and gut microbiome composition. Using structural equation modeling, we will explore how upstream risk factors, including early life events, current discrimination, and community food access, may influence food insecurity and its potential downstream impacts, including diet, other lifestyle risk behaviors, and chronic inflammation, with insulin resistance as the ultimate outcome variable. Findings from these analyses of observational data will inform the subsequent study aims, which involve qualitative exploration of significant pathways, followed by development and testing of a low-DII^® food as medicine intervention to reverse insulin resistance among PLWH (ClinicalTrials.gov Identifier: NCT05208671).

Discussion:

The NOURISH-OK study will address important research gaps to inform the development of food as medicine interventions to support healthy aging for PLWH.

Dietary Inflammatory Index in relation to Type 2 Diabetes: A Meta-Analysis

Background and Aims

Epidemiologic studies show a strong association between chronic inflammation and type 2 diabetes (T2D). Diet may also affect the risk of T2D by modulating inflammation. This meta-analysis aimed to assess the relation of dietary inflammatory index (DII) and risk of T2D.

Methods

PubMed and Scopus were systematically searched from their inception to September 2020 to identify relevant studies. Relative risks, hazard ratios, or odds ratios (OR), with their corresponding 95% confidence intervals (95% CI), were calculated and pooled using a random-effects model.

Results

A total of 48 different studies, with a total sample size of 1,687,424 participants, were eligible to be included in this meta-analysis. In the overall analysis, no significant association was observed between DII and risk of T2D (OR = 1.03, 95% CI: 0.91 to 1.15), with significant evidence for heterogeneity (I 2  = 96.5%, P < 0.001); however, higher DII was identified as being significantly related to increased risk of T2D in high quality studies (OR = 1.58, 95% CI: 1.15 to 2.17). In the stratified analysis by the dietary assessment tool, background disease, and sex of participants, DII showed no significant association with T2D.

Conclusions

Higher DII might be associated with an increased risk of T2D. Additional well-designed studies are required to confirm this finding.

Associations of Dietary Inflammatory Index With Prediabetes and Insulin Resistance

BACKGROUND AND AIMS

Previous studies suggested that dietary inflammatory index (DII) was associated with a variety of adverse health conditions. However, less is known about the role of DII in prediabetes and insulin resistance (IR). Therefore, this study aimed to investigate whether DII is associated with prediabetes and IR in American adults.

METHOD AND RESULTS

DII scores were calculated using the average of two 24-hour dietary recalls. Linear regression models were performed to evaluate the associations of DII with markers of Type 2 diabetes (T2D) risk, and the associations of DII with prediabetes and IR were estimated using logistic regression model. The diet of the participants showed an anti-inflammatory potential, with a mean DII score of -0.14 (range: -5.83 to +5.32). After controlling for multiple potential confounders, DII scores were positively associated with fasting plasma glucose (FPG) (β: 0.009; 95%CI: 0.005 to 0.012), fasting serum insulin (FSI) (β: 0.083; 95%CI: 0.067 to 0.099) and homeostatic model assessment of insulin resistance (HOMA-IR) (β: 0.092; 95%CI: 0.075 to 0.109). Participants in the highest tertile of DII score have increased odds of prediabetes (OR: 1.40; 95%CI: 1.17 to 1.69; P for trend <0.001) and IR (OR: 1.79; 95%CI: 1.49 to 2.14; P for trend <0.001) compared with those in the first tertile of DII score.

CONCLUSIONS

This study indicates that DII was positively associated with FPG, FSI, and HOMA-IR, and a more pro-inflammatory diet was related to increased odds of insulin resistant and prediabetes.

The dietary inflammatory index, obesity, type 2 diabetes, and cardiovascular risk factors and diseases

An unhealthy diet is a recognized risk factor in the pathophysiology of numerous chronic noncommunicable diseases (NCD), including obesity, type 2 diabetes (T2DM), and cardiovascular diseases (CVD). This is, at least in part, due to unhealthy diets causing chronic low-grade inflammation in the gut and systemically. To characterize the inflammatory potential of diet, we developed the Dietary Inflammatory Index (DII®). Following this development, around 500 papers have been published, which examined the association between the DII, energy-adjusted DII (E-DII™), and the children's DII (C-DII™) and many chronic NCDs including obesity and cardiometabolic diseases. Although a previous narrative review published in 2019 briefly summarized the evidence in this area, there was a significant increase in papers on this topic since 2020. Therefore, the purpose of this narrative review is to provide an in-depth updated review by including all papers until July 2021 on DII and its relationship with obesity, T2DM, and CVD. Furthermore, we aim to identify potential gaps in the literature and provide future directions for research. Most studies found that DII was associated with an increased risk of obesity, T2DM, and CVD with some relationships being sex-specific. However, we identified the paucity of papers describing associations between dietary inflammation and T2DM and its risk factors. Few studies used gold-standard measures of cardiometabolic risk factors. We also identified the lack of interventional studies designed to change the inflammatory potential of diets and study its effect on cardiometabolic risk factors and diseases. We recommend that such interventional studies are needed to assess if changes in DII, representing the inflammatory potential of diet, independently of changes in body composition can modulate cardiometabolic risk factors and diseases.

Influence of pro-obesogenic dietary habits on stress-induced cognitive alterations in healthy adult volunteers

Stress is a fundamental biological response that can be associated with alterations in cognitive processes. Unhealthy dietary habits are proposed to modulate this effect, notably through their pro-inflammatory potential. This cross-sectional study aimed to evaluate the influence of an obesogenic dietary pattern with inflammatory potential on stress-induced cognitive alterations in healthy volunteers. Fifty healthy adult participants were stratified into two diet groups: obesogenic vs. non-obesogenic, based on their self-reported consumption of fat, sugar, and salt, assessed by the French National Program for Nutrition and Health questionnaire and a food frequency questionnaire. Serum high-sensitive C-reactive protein (hsCRP) was measured as a marker of systemic inflammation using ELISA. Verbal memory and sustained attention were evaluated through the Verbal Recognition Memory (VRM) test and the Rapid Visual Information Processing (RVP) test respectively, from the Cambridge Neuropsychological Test Automated Battery. Assessments were performed before and after exposure to the psychological stressor Trier Social Stress Test (TSST). Stress response was evaluated by subjective stress perception, salivary cortisol, blood pressure, and heart rate. Twenty-two participants (44%) presented an obesogenic diet. Systemic inflammation was significantly higher in the obesogenic diet group (p=0.005). The TSST induced a significant stress response, regardless of dietary habits (Time effect p < 0.001). In the whole sample, exposure to TSST was associated with cognitive changes in the form of impaired performance on the VRM test and overall improved RVP scores. However, the obesogenic diet group exhibited an increased total number of false alarms (Time x Diet: p=0.014) on the RVP test after TSST exposure as well as a greater impairment in immediate verbal recognition on the VRM test (Time x Diet: p=0.002). This effect was not associated with the inflammatory component of the obesogenic diet. These results suggest that an obesogenic diet may sensitize healthy individuals to the detrimental effects of acute stress on cognitive performance.

Investigating Associations Between Depressive Symptoms and Anti-/Pro-Inflammatory Nutrients in an Elderly Population in Northern China: A Bayesian Kernel Machine Regression Approach

Backgroud

The potential for dietary inflammation has been shown to be associated with a variety of chronic diseases. The relationship between the potential for dietary inflammation and depression in the elderly is unclear.

Objective

This study aimed to exam the relationship between different nutrients and the risk of depression symptoms in the elderly.

Methods

In total, 1865 elderly in northern China were investigated at baseline from 2018 to 2019 and followed up in 2020. We measured the baseline intake of 22 nutrients and used Least Absolute Shrinkage and Selection Operator(LASSO) regression analysis and Bayesian Kernel Machine Regression (BKMR) to explore the association between exposure to a variety of nutrients with different inflammatory potentials and the risk of depressive symptoms.

Results

A total of 447 individuals (24.0%) were diagnosed with depressive symptoms. Through the lasso regression model, it was found that 11 nutrients are significantly related to the risk of depressive symptoms, of which 6 nutrients are pro-inflammatory nutrients (inflammation effect score>0), and 5 are anti-inflammatory nutrients (inflammation effect score<0). We incorporated the inflammatory effect scores of 11 nutrients into the BKMR model at the same time, and found that the overall inflammatory effect of 11 nutrients increased with the increase of total inflammatory scores, suggesting that the overall effect was pro-inflammatory. BKMR subgroup analysis shows that whether in the pro-inflammatory nutrient group or the anti-inflammatory nutrient group, multiple nutrients have a significant combined effect on depressive symptoms. By comparing the overall and group effects, we found that the inflammatory effects of the pro-inflammatory diet and the anti-inflammatory diet in the study’s diet are offset by each other (P<0.005).

Conclusion

We determined the combined effect of multiple nutrients of different inflammatory potential classifications on depressive symptoms in the elderly.

Circulating Inflammation Markers Partly Explain the Link Between the Dietary Inflammatory Index and Depressive Symptoms

BACKGROUND

Depression is a mood disorder characterized by a high rate of resistance to pharmacological treatments, which has often been linked to chronic inflammation. This can be influenced by different environmental factors, in particular pro-inflammatory diets. However, a mediating role of circulating inflammation has never been observed.

AIM

To test the association between a dietary inflammatory index (DII®) and continuous depressive symptoms (adapted version of PHQ9) in an Italian population cohort (N=13,301), along with potential explanatory effect of a composite index (INFLA-score) based on four circulating inflammatory biomarkers: C-reactive protein, granulocyte-to-lymphocyte ratio, platelet and white blood cell counts.

RESULTS

Significant positive associations were observed between DII and total depressive symptoms (standardized β (SE) = 0.038 (0.005), p < 0.001), and with two factors tagging somatic (0.012 (0.003), p < 0.001) and cognitive symptoms (0.012 (0.003), p < 0.001), after adjustment for different potential confounders (socioeconomic status, chronic health conditions and lifestyles). These associations were about twice as strong in women than in men. INFLA-score explained a small but significant proportion of the association with total depressive symptoms (0.90-2.30%, p < 0.05), which was mainly driven by granulocyte-to-lymphocyte ratio (1.18-1.65%). This effect was even stronger for the somatic (2.66-4.66%) but not for the cognitive factor (0%).

CONCLUSION

These findings support a strong link between inflammatory diet and depression, especially with somatic symptoms and within women. Moreover, they provide novel evidence for a potential explanatory role of circulating inflammation in this association, suggesting new paths for prevention and treatment of major and atypical depression.

Assessing the (anti)-inflammatory potential of diets

PURPOSE OF REVIEW

It is accepted that several chronic diseases are associated with inflammation. Dietary habits and the consumption of certain nutrients have been shown to influence inflammation, reflected by inflammatory cytokines. In this narrative review, we discuss currently developed tools to assess the inflammatory potential of diets and compare them with established tools.

RECENT FINDINGS

Four new indices were recently developed. The Inflammatory Score of the Diet is a modified version of the established Dietary Inflammatory Index. The novel Empirical Dietary Inflammatory Index works without previous dietary intake assessment and the Anti-Inflammatory Diet Index was specifically developed in a northern European population. The Dietary and Lifestyle Inflammation Scores addresses additional confounders. The informative value of dietary indices relies on the accuracy and completeness of dietary intake assessment.

SUMMARY

Dietary inflammatory indices are important tools to assess, compare and validate the inflammatory potential of diets across populations without the need for biomarker assessments. They allow to investigate associations between an (anti)-inflammatory diet with disease risk and course. Although the Dietary Inflammatory Index remains the most used index worldwide, currently developed indices allow more flexibility, have a different focus or simplify assessment. Additional foods, that were recently shown to modulate inflammation, but are not (fully) considered yet, may deserve more attention in the future.

Association between dietary inflammatory index and serum C-reactive protein concentrations in the Japan Collaborative Cohort Study

Diet plays an important role in the regulation of chronic inflammation, which is linked to cardiovascular disease (CVD) and several cancers. The dietary inflammatory index (DII^®) was developed to estimate the inflammatory potential of an individual’s diet. We examined the association between DII scores and serum high-sensitivity C-reactive protein (hs-CRP) concentrations using the baseline data from the Japan Collaborative Cohort Study (JACC Study). Data were from 1176 control subjects (650 men and 526 women) in a nested case-control study of several cancers and CVD in the JACC Study who were free of cancer and CVD at baseline. DII scores were calculated from 26 food parameters that were derived from a validated food frequency questionnaire administered at the baseline. Energy-adjusted DII scores were calculated using the residual method. Serum hs-CRP concentrations were measured by latex-enhanced nephelometry or enzyme-immunoassay. In multivariable logistic regression analysis adjusting for potential confounders including sex, age, smoking habits, drinking habits, body mass index, and history of hypertension, the odds ratio (OR) and 95% confidence intervals (CI) for high serum hs-CRP concentrations (>1.0 mg/L) was significantly higher in the highest versus the lowest DII quartile (OR_Quartile4vs1 = 1.32, 95% CI = 1.01 to 2.52). Likewise, a 1-point increase in DII score was associated with a 14% increased risk of high serum hs-CRP concentrations (OR_Continuous = 1.09, 95%CI = 1.01 to 1.19). A pro-inflammatory diet, as represented by high DII scores, was associated with high serum hs-CRP concentrations in this Japanese population.

Dietary Inflammatory Index Is Associated With Inflammation in Japanese Men

Background: Dietary components are known to affect chronic low-grade inflammation status. The dietary inflammatory index (DII®) was developed to measure the potential impact of a diet on an individual's inflammatory status, and it has been validated mainly in Western countries.

Objective: This study aimed to examine the validity of the energy-adjusted DII (E-DII^TM) using high-sensitivity C-reactive protein (hs-CRP) concentration in Japanese men and women.

Methods: In total, 6,474 volunteers from a cancer-screening program (3,825 men and 2,649 women) completed a food frequency questionnaire (FFQ) and their hs-CRP concentrations were evaluated. E-DII scores were calculated on the basis of 30 food parameters derived from the FFQ. Higher E-DII scores reflect a greater pro-inflammatory potential of the diet. The associations between E-DII quartiles and hs-CRP concentration were assessed using regression models adjusted for age, body mass index, smoking status, and amount of physical activity.

Results: Mean E-DII in men and women was + 0.62 ± 1.93 and −1.01 ± 2.25, respectively. The proportion of men and women who had hs-CRP concentration >3 mg/L was 4.7 and 3.1%, respectively. A significant positive association was observed between E-DII score and hs-CRP concentration in men; geometric mean of hs-CRP concentration in the lowest and highest E-DII quartiles was 0.56 mg/L and 0.67 mg/L (P_trend < 0.01), respectively. The odds ratio (95% confidence interval) of having an elevated hs-CRP concentration (>3 mg/L) was 1.72 (1.10–2.67) in the highest E-DII quartile (P_trend = 0.03) in men. However, no association was observed between E-DII score and hs-CRP concentration in women, except in those not taking prescription medications.

Conclusions: DII was associated with inflammation status in Japanese men, but the association was limited in Japanese women.

Negative Association Between Mediterranean Diet Adherence and COVID-19 Cases and Related Deaths in Spain and 23 OECD Countries: An Ecological Study

In December 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-Cov2) emerged in Wuhan, China, sparking the Coronavirus disease 2019 (COVID-19) pandemic. The high prevalence of nutrition-related COVID-19 risk factors including obesity, type 2 diabetes, and hypertension, suggests that healthy dietary approaches may mitigate COVID-19 related outcomes and possibly SARS-CoV-2 infection. Based on the fundamental role of nutrition in immune function and the well-documented association between Mediterranean diet consumption and risk reduction for chronic diseases that are comorbidities in COVID-19 patients, we hypothesized that there would be a relationship between Mediterranean diet adherence and COVID-19 cases and related deaths. In this perspective, we examined the association between regional adherence to a Mediterranean diet and COVID-19 cases and deaths using an ecological study design. We observed that Mediterranean diet adherence was negatively associated with both COVID-19 cases and related deaths across 17 regions in Spain and that the relationship remained when adjusted for factors of well-being. We also observed a negative association between Mediterranean diet adherence and COVID-19 related deaths across 23 countries when adjusted for factors of well-being and physical inactivity. The anti-inflammatory properties of the Mediterranean diet - likely due to the polyphenol content of the diet - may be a biological basis to explain our findings. However, there are confounding factors unrelated to dietary factors driving COVID-19 cases and related deaths across the regions in Spain and the 23 countries examined in our analysis. Our findings will need to be confirmed and further explored in cohort studies.

Link between Viral Infections, Immune System, Inflammation and Diet

The strong spread of COVID-19 and the significant number of deaths associated with it could be related to improper lifestyles, which lead to a low-grade inflammation (LGI) that not only increases the risk of chronic diseases, but also the risk of facing complications relating to infections and a greater susceptibility to infections themselves. Recently, scientific research has widely demonstrated that the microbiota plays a fundamental role in modulating metabolic responses in the immune system. There is, in fact, a two-way interaction between lifestyle, infection, and immunity. The immune response is compromised if nutrition is unbalanced or insufficient, because diet affects the intestinal flora predisposing people to infections and, at the same time, the nutritional state can be aggravated by the immune response itself to the infection. We evaluate the link between balanced diet, the efficiency of the immune system, and microbiota with the aim of providing some practical advice for individuals, with special attention to the elderly. A correct lifestyle that follows the Mediterranean model, which is especially rich in plant-based foods along with the use of extra-virgin olive oil, are the basis of preventing LGI and other chronic pathologies, directly influencing the intestinal microbiota and consequently the immune response.

Association Between Inflammatory Potential of the Diet and Ulcerative Colitis: A Case-Control Study

Background/Aim: Despite the inflammatory nature of inflammatory bowel disease (IBD), limited data are available on the association of inflammatory potential of the diet and risk of ulcerative colitis (UC). We aimed to investigate the association of inflammatory potential of the diet (IPD) score and odds of UC in a case-control study. Methods: Patients with UC were enrolled from Iranian IBD registry, whose disease was confirmed by a gastroenterologist. Controls were selected randomly from the Study of the Epidemiology of Psycho Alimentary Health and Nutrition (SEPAHAN) study, a large population-based study on more than 8,000 apparently healthy individuals. Dietary intakes of 28 food items obtained from a validated dish-based food frequency questionnaire (FFQ), were used to compute IPD score. Results: This case-control study was carried out among 109 cases and 218 randomly chosen controls. Mean age of cases and controls was 39.5 ± 10.0 and 41.5 ± 11.8 y, respectively. Totally, 52% of study participants were female and 48% were male. After controlling for age, sex, and body mass index (BMI), we found that the patients with UC were more likely to be in the highest quartile of IPD score compared with controls (OR: 2.83; 95% CI: 1.41-5.69, P-trend < 0.001). This association strengthened after additional adjustment for education, smoking, medical history, and physical activity (OR: 3.48; 95% CI: 1.32-9.10, P-trend = 0.003). When we took dietary habits into account, the association was slightly attenuated (OR: 3.33; 95% CI: 1.20-9.20, P-trend = 0.005). Conclusions: We found that adherence to a pro-inflammatory diet was positively associated with greater odds of UC. Further studies are required to confirm these findings.

Dietary inflammatory index (DII®) and the risk of depression symptoms in adults

BACKGROUND & AIMS

Findings from observational studies investigating the association between Dietary Inflammatory Index (DII®) scores and depression symptoms (DepS) are inconsistent. This study aims to assess the association between energy-adjusted DII (E-DII™) and DepS using the North West Adelaide Health Study (NWAHS) cohort as well as update a previous meta-analysis.

METHODS

A total of 1743 (mean ± SD age: 56.6 ± 13.6 years, 51% female) study participants from NWAHS were included in the cross-sectional study and 859 (mean ± SD age: 58.4 ± 12.1 years, 52.6% female) in the longitudinal analyses. The Center for Epidemiological Studies Depression Scale (CES-D) was used for the measurement of DepS. E-DII scores were calculated from the dietary data collected using a validated food frequency questionnaire (FFQ). Data from two stages [Stage 3 (2008-10) and North West 15 (NW15) (2015)] were used. Log- and negative binomial regression were used to assess the association between quartiles of E-DII and DepS. A recent meta-analysis was updated by including 12 publications (six cross-sectional and six cohort studies) on the association between DII and DepS.

RESULTS

In the cross-sectional analysis, a higher E-DII score (i.e., more pro-inflammatory diet) was associated with a 79% increase in odds of reporting DepS [OR_Quartile4vs1: 1.79; 95% CI: 1.14-2.81; p = 0.01; p for trend (p_trend) = 0.03]. Males with higher E-DII had a more than two-fold higher odds of DepS (OR_Quartile4vs1: 2.27; 95% CI: 1.02-5.06; p = 0.045; p_trend = 0.09). Females with higher E-DII had an 81% increase in odds of DepS (OR_Quartile4vs1: 1.81; 95% CI: 1.01-3.26; p = 0.046; p_trend = 0.07). These associations were consistent in the longitudinal analysis. Comparing highest to lowest quintiles of E-DII, the updated meta-analysis showed that a pro-inflammatory diet is associated with a 45% increase in odds of having DepS (OR: 1.45; 95% CI: 1.20-1.74; p < 0.01) with higher odds in females (OR: 1.53; 95% CI: 1.16-2.01; p = 0.01) compared to their male counterparts (OR: 1.29; 95% CI: 0.98-1.69; p = 0.15).

CONCLUSION

The data from the NWAHS and the updated meta-analysis of observational studies provide further evidence that a pro-inflammatory diet is positively associated with increased risk of DepS. These findings support the current recommendation on consuming a less inflammatory diet to improve DepS.

A cross-talk between gut microbiome, salt and hypertension

Cardiac disorders contribute to one of the major causes of fatality across the world. Hypertensive patients, even well maintained on drugs, possess a high risk to cardiovascular diseases. It is, therefore, highly important to identify different factors and pathways that lead to risk and progression of cardiovascular disorders. Several animals and human studies suggest that taxonomical alterations in the gut are involved in the cardiovascular physiology. In this article, with the help of various experimental evidences, we suggest that the host gut-microbiota plays an important in this pathway. Short chain fatty acids (SCFAs) and Trimethyl Amine -n-Oxide (TMAO) are the two major products of gut microbiome. SCFAs present a crucial role in regulating the blood pressure, while TMAO is involved in pathogenesis of atherosclerosis and other coronary artery diseases, including hypertension. We prove that there exists a triangular bridge connecting the gap between dietary salt, hypertension and gut microbiome. We also present some of the dietary interventions which can regulate and control microbiota that can prevent cardiovascular complications.We strongly believe that this article would improve the understanding the role of gut microbiota in hypertension, and will be helpful in the development of novel therapeutic strategies for prevention of hypertension through restoring gut microbiome homeostasis in the near future.

Dietary inflammatory index significantly affects lipids profile among adults: An updated systematic review and meta-analysis

Background: The available data on the relationship between dietary inflammatory index (DII^®) and serum lipids are controversial. This systematic review and meta-analysis aimed to investigate the relationship between DII^® and serum lipids, including total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglyceride (TG) in general populations. Methods: PubMed, Web of Science, SCOPUS, and Cochrane electronic databases were systematically searched from inception to December 2019. Case-control, cohort or cross-sectional studies that evaluated the relationship between DII^® and serum lipids were included. The random-effects model was applied to evaluate the pooled weighted mean difference (WMD) and 95% confidence intervals (CI). Results: In total, twenty-four cross-sectional and one case-control studies with a total sample size of 129,759 were included in the meta-analysis. The pooled results showed that the highest category of DII^® was associated with 5.16 mg/dl increase in TC (Pooled WMD: 5.16; 95% CI: 0.58-9.73, p = 0.02) and 3.99 mg/dl increase in LDL-C (Pooled WMD: 3.99; 95% CI: 1.16-6.81, p = 0.006). However, no significant association between DII^® scores, HDL-C and TG was found. In subgroup analysis, the geographical region, gender, and dietary assessment methods were potent sources of heterogeneity. Conclusion: This study showed that a higher level of DII^® was associated with higher levels of TC and LDL-C in apparently healthy populations. Since the included studies had observational designs, therefore, no conclusion of causality was possible. More studies with interventional designs are required to elucidate the causality of the observed association between DII^® and the risk of abnormal lipid profile.

Dietary inflammatory index score, glucose control and cardiovascular risk factors profile in people with type 2 diabetes

We examined the relationships between the dietary inflammatory index (DII^®), dietary habits and cardiovascular risk factor profiles in people with type 2 diabetes mellitus (T2DM). Energy-adjusted DII (E-DII™) scores were calculated from a Food Frequency Questionnaire in 2568 T2DM patients from different parts of Italy. Analyses were conducted according to quartiles of sex-specific E-DII scores. Higher, more pro-inflammatory, (quartile 4) E-DII scores were associated with overall poor quality of the diet characterised by higher content of refined carbohydrates, added sugars, saturated fat and cholesterol and lower unsaturated fat, fibre and polyphenols compared to quartile 1. Higher E-DII scores also were associated with higher waist circumference (105.4 vs. 103.5 cm; p = 0.002), triglycerides (154.6 vs. 146.1 mg/dL; p = 0.005), diastolic blood pressure (80.05 vs. 78.6 mmHg; p = 0.04) and lower HDL-cholesterol (45.3 vs. 47.4 mg/dL; p = 0.04). In conclusion, E-DII is a potent marker of overall quality of the diet and is associated with an unfavourable cardiovascular risk factor profile.

Inflammatory potential of diet and risk of incident knee osteoarthritis: a prospective cohort study

Background

To examine the relation between inflammatory potential of diet and incident knee osteoarthritis (OA) and the role of BMI in the association of interest.

Methods

In the Osteoarthritis Initiative, the energy-adjusted dietary inflammatory index (E-DII™) scores were calculated based on the Block Brief 2000 Food Frequency Questionnaire and categorized into sex-specific quartiles. Outcomes were incident (1) radiographic knee OA (ROA) (i.e., a KL grade ≥ 2) and (2) symptomatic knee OA (SxOA) (i.e., a combination of frequent knee pain and ROA). We fitted generalized estimating equation models to examine the association between E-DII scores and incident knee OA. We performed mediation analyses to assess the potential mediation by BMI in the DII-OA relation.

Results

Over a 48-month follow-up period, 232 and 978 knees developed ROA and SxOA, respectively. Compared with the lowest (most anti-inflammatory) E-DII quartile, the odds ratio (OR) of incident ROA for the highest (most pro-inflammatory) E-DII quartile was 1.73 (95% confidence interval (CI) 1.15 to 2.62, P_trend = 0.007). The corresponding OR for SxOA was 1.43 (95% CI 1.16 to 1.76, P_trend = 0.001). The DII-OA association was significantly mediated via BMI with an indirect effect of 1.08 (95% CI 1.04, 1.13) for ROA and 1.13 (95% CI 1.09, 1.16) for SxOA, accounting for 20.4% and 44.5% of the total effect, respectively.

Conclusions

A higher inflammatory potential of diet increased the risk of knee OA. The association was significantly mediated via BMI. Targeting the inflammatory potential of diet may be beneficial to reduce the risk of knee OA.

Sleep quality and Dietary Inflammatory Index among university students: a cross-sectional study

PURPOSE

Evidence indicates that most college students face reduced sleep quality due to unhealthy dietary habits and hectic daily schedules. While the relationship between sleep quality and general health has been the subject of intensive research, little is known about the association between sleep and its relation with the inflammatory potential of the diet until recently. This study aimed to investigate the association between Energy-Adjusted Dietary Inflammatory Index (E-DII^®) scores and sleep quality in a group of students from the University of Sharjah (UOS).

METHODS

A cross-sectional study design was followed, and convenience sampling was used. Participants were assessed for sleep quality using the Pittsburgh Sleep Quality Index (PSQI), E-DII scores were derived from a semi-quantitative food frequency questionnaire (FFQ), and physical activity level was measured using the International Physical Activity Questionnaire (IPAQ). Chi-square tests and two-sample t tests were used to find an association between E-DII scores and sleep quality.

RESULTS

A total of 379 college students were included in the study of whom 64 % were female and 81% were between 18 and 21 years of age. Two-thirds of participants experienced poor sleep quality. Although results were trending in the hypothesized direction, no significant association was found between E-DII scores and sleep quality. Among the individual components of sleep quality, a direct significant association was found between E-DII scores and day dysfunction (P = 0.03).

CONCLUSIONS

These results suggest that a pro-inflammatory diet maybe related to increased day dysfunction among UOS students. Consuming a more anti-inflammatory diet may reduce daytime dysfunction. Further prospective and controlled studies are required to confirm this association, and to explore other attributes and their sequelae on sleep quality.

Dietary inflammatory index potentially increases blood pressure and markers of glucose homeostasis among adults: findings from an updated systematic review and meta-analysis

OBJECTIVE

In the current meta-analysis, we aimed to systematically review and summarize eligible studies for the association between dietary inflammatory index (DII) and blood pressure, hypertension (HTN) and glucose homeostasis biomarkers.

DESIGN/SETTING

In a systematic search of PubMed, Scopus and Google Scholar electronic databases up to February 2019, relevant studies were included in the literature review. Observational studies evaluating the association between DII and HTN, hyperglycaemia, systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), insulin, homeostatic model assessment of insulin resistance (HOMA-IR) and glycated Hb (HbA1c) were included.

PARTICIPANTS

Not applicable.

RESULTS

Total numbers of studies were as follows: OR for DII and HTN (n 12), OR for DII and hyperglycaemia (n 9), HTN prevalence (n 9), mean (sd) of SBP and DII (n 12), mean (sd) of DBP and DII (n 10), mean (sd) of FBS and DII (n 13), mean (sd) of HbA1c and DII (n 3), mean (sd) of insulin and DII (n 6), mean (sd) of HOMA-IR and DII (n 7). Higher DII scores were associated with higher odds of HTN (OR = 1·13; 95 % CI 1·01, 1·27; P < 0·001), SBP (weighted mean difference (WMD) = 1·230; 95 % CI 0·283, 2·177; P = 0·011), FBS (WMD = 1·083; 95 % CI 0·099, 2·068; P = 0·031), insulin (WMD = 0·829; 95 % CI 0·172, 1·486; P = 0·013), HbA1c (WMD = 0·615; 95 % CI 0·268, 0·961; P = 0·001) and HOMA-IR (WMD = 0·192; 95 % CI 0·023, 0·361; P = 0·026) values compared with lowest DII categories.

CONCLUSIONS

Lower inflammatory content of diets for prevention of cardiovascular risk factors is recommended.

Influence of magnitude of weight loss on Adipo/lep ratio in adolescents with obesity undergoing multicomponent therapy

BACKGROUND AND AIMS

The expansion of adipose tissue increases leptin secretion associated with a reduction of adiponectin concentration, which negatively affects health of adolescents with obesity. This study aims to investigate the effects of non-intensive interdisciplinary therapy on cardiometabolic parameters including leptin, adiponectin and adiponectin/leptin ratio as a dependent manner on its magnitude of weight loss reduction.

METHODS AND RESULTS

Thirty-eight adolescents (14-19 y.o) were enrolled in an interdisciplinary therapy for 20 weeks. Body composition, biochemical parameters, leptin and adiponectin were measured at baseline and after therapy. The adolescents were divided into two groups according to the magnitude of total weight loss, less than 5% (<5%-n = 18) or greater than or equal to 5% (≥5%-n = 20). Leptin decreased in whole group after therapy, while adiponectin, and adiponectin/leptin ratio increased. Additionally, body composition was improved. Only the group who lost ≥5% of body weight could reduce the inflammatory state.

CONCLUSION

The interdisciplinary therapy contributes to improve cardiometabolic parameters that could be involved on inflammation in adolescents with obesity, this improvement occurred mainly when the weight loss is ≥5% of body weight. It could be a target for control the inflammatory process related to obesity in adolescents.

The association between dietary inflammatory index and risk of central obesity in adults: An updated systematic review and meta-analysis

Backgrounds: Central obesity, as a pivotal component of metabolic syndrome is associated with numerous co-morbidities. Dietary factors influence central obesity by increased inflammatory status. However, recent studies didn't evaluate the association between central obesity and dietary inflammation index (DII^®) that give score to dietary factors according to their inflammatory potential. In the current systematic review and meta-analysis, we summarized the studies that investigated the association between DII^® with central obesity indices in the general populations. Methods: In a systematic search from PubMed, SCOPUS, Web of Sciences and Cochrane electronic databases, we collected relevant studies written in English and published until 30 October 2019. The population of included studies were apparently healthy subjects or individuals with obesity or obesity-related diseases. Observational studies that evaluated the association between DII^® and indices of central obesity including WC or WHR were included. Results: Totally thirty-two studies were included; thirty studies were cross-sectional and two were cohort studies with 103071 participants. Meta-analysis of observational studies showed that higher DII^® scores were associated with 1.81 cm increase in WC (Pooled weighted mean difference (WMD) = 1.813; CI: 0.785-2.841; p = 0.001). Also, a non-significant increase in the odds of having higher WC (OR = 1.162; CI: 0.95-1.43; p = 0.154) in the highest DII category was also observed. In subgroup analysis, the continent, dietary assessment tool and gender were the heterogeneity sources. Conclusion: The findings proposed that adherence to diets with high DII^® scores was associated with increased WC. Further studies with interventional designs are necessary to elucidate the causality inference between DII^® and central obesity indices.

Lifestyle and biological factors influence the relationship between mental health and low-grade inflammation

Mental health modulates the risk of common chronic conditions. Although inflammation is thought to partly explain this link, its relation with mental health is still unclear and largely unexplored. We investigated three scales assessing psychological resilience (CD-RISC), depression symptoms (PHQ9-6) and mental wellbeing (SF36-MCS) in an Italian adult population cohort (N_max = 16,952). This showed a slightly higher frequency of men, more educated and younger participants, compared to samples with incomplete questionnaires. We performed stepwise generalized linear models to test the association between each scale and INFLA-score, a composite blood-based inflammation index. At each step, a class of potential mediators was included in the model, namely health conditions, lifestyle factors, or both (full model). Full model analysis was also conducted on single blood markers involved in the inflammatory process. In the baseline model, we observed significant associations of PHQ9-6 (standardized β(SE) = 0.024(0.009), p = 8.9 × 10^-3) and SF36-MCS (β(SE) = -0.021(0.008), p = 7 × 10^-3) with INFLA-score. These associations survived adjustment for health conditions but not for lifestyle factors, which explained 81% and 17% of the association with PHQ9-6 and SF36-MCS. Significant associations (p < 4.2 × 10^-3) after mediator adjustment were observed for single low-grade inflammation markers, including platelet distribution width (with PHQ9-6 and CD-RISC), granulocyte- and neutrophil-to-lymphocyte ratios, monocyte and lymphocyte fractions (with SF36-MCS). After imputation of missing data, we observed substantially consistent associations. These findings suggest that the relationship between mental health and low-grade inflammation is largely influenced by lifestyle. However, the associations with specific biomarkers related to inflammation are partly independent and might be explained by biological factors.

Dietary Inflammatory Index and S-Klotho Plasma Levels in Middle-Aged Adults

Background: Soluble Klotho (S-Klotho) is an aging suppressor with a close link with inflammation. However, it is still unknown whether the dietary inflammatory potential is associated with S-Klotho plasma level. We aimed to investigate the association of the Dietary Inflammatory Index (DII) with S-Klotho plasma levels in middle-aged sedentary adults. Methods: 73 middle-aged sedentary adults (40–65 years old) participated in the present study. DII was determined from 28 dietary items obtained by 24 h recalls and food frequency questionnaires. The S-Klotho plasma levels were measured using a solid-phase sandwich enzyme-linked immunosorbent assay. Results: a weak positive association was observed between DII and S-Klotho plasma levels (β = 52.223, R² = 0.057, p = 0.043), which disappeared after controlling for body mass index (p = 0.057). Conclusions: A pro-inflammatory dietary pattern measured with the DII was slightly and positively associated with S-Klotho plasma levels in middle-aged sedentary adults.

The Dietary Inflammatory Index Is Positively Associated with Colorectal Cancer Risk in a Chinese Case-Control Study

Diet may modulate chronic inflammation. The aim of this study is to investigate whether the dietary inflammatory index (DII^®) was associated with the risk of colorectal cancer in a Chinese population. A case-control study was conducted from July 2010 to April 2019, in Guangzhou, China. A total of 2502 eligible cases were recruited along with 2538 age- (5-year interval) and sex-matched controls. Dietary data derived from a validated food frequency questionnaire were used to calculate the energy-adjusted DII (E-DII) scores. Odds ratios (ORs) and 95% confidence intervals (CIs) for colorectal cancer risk were estimated using unconditional logistic regression models. In this study, E-DII scores ranged from -5.96 (the most anti-inflammatory score) to +6.01 (the most pro-inflammatory score). A positive association was found between the E-DII and colorectal cancer risk, with the OR = 1.40 (95% CI 1.16, 1.68; P_trend < 0.01) for the highest E-DII quartile compared with the lowest quartile after adjusting for potential confounders. When stratified based on cancer subsite, sex, body mass index, and smoking status, significant associations were not observed in women or underweight individuals. Results from this study confirmed that a higher E-DII score was associated with an increased risk of colorectal cancer in a Chinese population.

Impact of a 3-Month Anti-inflammatory Dietary Intervention Focusing on Watermelon on Body Habitus, Inflammation, and Metabolic Markers: A Pilot Study

An anti-inflammatory dietary intervention called the Inflammation Management Intervention (IMAGINE) was adapted to emphasize watermelon due to its anti-inflammatory properties. This pilot study (n = 23) tested the effect of a watermelon-enhanced IMAGINE intervention (n = 15) on body habitus and markers of inflammation and metabolism. This 3-month self-selection trial, consisting of weekly in-person classes and online education for 12 weeks, focused on incorporating watermelon into an already anti-inflammatory diet. Controls (n = 8) received basic health education via email and blogs. Measurements, including diet, anthropometrics, actigraphy, and a blood draw, were made at baseline and immediately postintervention. Linear regression analyses were conducted using intervention status as the main exposure. Post hoc analyses then ignored intervention assignment and grouped participants based on their change in their energy-adjusted Dietary Inflammatory Index (E-DIITM) score. There were no group-by-time interactions for any of the studied outcomes. However, some intervention participants' diets became more proinflammatory, and several control participants' diets became more anti-inflammatory. Those participants below the median of E-DII change (ie, more anti-inflammatory changes) showed reductions in body fat percent (-1.27% vs +0.90%, respectively, P = .01), body mass index (-0.66 vs +0.38 kg/m2, respectively, P = .06) and body weight (-0.99 vs +0.54 kg, respectively, P = .08) compared to those above the median of E-DII change. This study demonstrates that individuals who adopt a more anti-inflammatory diet containing watermelon will have improvements in body anthropometrics. Future studies should focus on increasing adherence and compliance to intervention prescriptions, exploring options to extend interventions to evaluate long-term changes, and further examining changes in inflammatory biomarkers. Clinical Trials Registration: NCT03158740.

Dietary inflammatory index and mortality: a cohort longitudinal study in a Mediterranean area

BACKGROUND

Higher Dietary Inflammatory Index (DII®) scores are associated with increased morbidity and mortality. However, little is known about the effects of DII on mortality in Mediterranean countries. Therefore, in the present study, we aimed to investigate the potential association between DII scores and overall, cancer and cardiovascular disease (CVD) mortality in people living in a Mediterranean area.

METHODS

DII scores were calculated using a validated food-frequency questionnaire. DII scores were then categorised into tertiles. Mortality was ascertained via death certificates. The association between DII scores with overall and cause-specific mortality was assessed via a multivariable Cox's regression analysis and reported as hazard ratios (HRs) with their 95% confidence intervals (CIs).

RESULTS

The study included 1565 participants (mean age 65.5 years; females 44.7%). After a median follow-up of 12 years (2005-2017), 366 (23.4%) participants died. After adjusting for 17 potential confounders, people with higher DII scores had an increased risk of death compared to those in the lowest (most anti-inflammatory) tertile (HR = 1.38; 95% CI = 1.04-1.82 for the second tertile; HR = 1.38; 95% CI = 1.03-1.86 for the third tertile). Each 1 SD increase in DII score increased the risk of death by 13%. No association was found between DII scores and cancer or CVD death when considered separately.

CONCLUSIONS

Higher DII scores were associated with a significantly higher mortality risk, whereas the association with cause-specific mortality was less clear. These findings highlight the potential importance of diet in modulating inflammation and preventing death.

Development and Validation of Novel Dietary and Lifestyle Inflammation Scores

BACKGROUND

Chronically higher inflammation, which may partly result from diet and lifestyle, is implicated in risk for multiple chronic diseases. The dietary inflammatory index (DII) and empirical dietary inflammatory pattern (EDIP), developed to characterize dietary contributions to systemic inflammation, have several limitations. There are no scores to characterize contributions of lifestyle to inflammation.

OBJECTIVES

To reflect dietary/lifestyle contributions to inflammation, we developed novel, inflammation biomarker panel-weighted, dietary (DIS) and lifestyle (LIS) inflammation scores in a subset (n = 639) of the Reasons for Geographic and Racial Differences in Stroke Study (REGARDS) cohort.

METHODS

We selected a priori 19 food groups and 4 lifestyle characteristics to comprise the DIS and LIS, respectively. We calculated the components' weights based on their strengths of association with an inflammation biomarker score [comprising high-sensitivity C-reactive protein (hsCRP), IL-6, IL-8, and IL-10] using multivariable linear regression. The sums of the weighted components constitute the scores, such that higher scores reflect, on balance, more proinflammatory exposures. We calculated the DIS, LIS, DII, and EDIP with cross-sectional data from the remaining REGARDS cohort (  n = 14,210 with hsCRP measurements) and 2 other study populations with hsCRP and/or an 8-component inflammation biomarker panel, and investigated their associations with circulating inflammation biomarker concentrations using multivariable logistic regression.

RESULTS

In REGARDS, those in the highest relative to the lowest DIS, LIS, DII, and EDIP quintiles had statistically significant 1.66-, 4.29-, 1.56-, and 1.32-fold higher odds of a high hsCRP concentration (>3 mg/dL), respectively (all P-trend < 0.001). Those in the highest relative to the lowest joint DIS/LIS quintile had a statistically significant 7.26-fold higher odds of a high hsCRP concentration. Similar findings were noted in the other 2 validation populations.

CONCLUSION

Our results support that dietary and lifestyle exposures collectively contribute substantially to systemic inflammation, and support the use of our novel DIS and LIS.

Dietary Inflammatory Index and Non-Communicable Disease Risk: A Narrative Review

There are over 1,000,000 publications on diet and health and over 480,000 references on inflammation in the National Library of Medicine database. In addition, there have now been over 30,000 peer-reviewed articles published on the relationship between diet, inflammation, and health outcomes. Based on this voluminous literature, it is now recognized that low-grade, chronic systemic inflammation is associated with most non-communicable diseases (NCDs), including diabetes, obesity, cardiovascular disease, cancers, respiratory and musculoskeletal disorders, as well as impaired neurodevelopment and adverse mental health outcomes. Dietary components modulate inflammatory status. In recent years, the Dietary Inflammatory Index (DII®), a literature-derived dietary index, was developed to characterize the inflammatory potential of habitual diet. Subsequently, a large and rapidly growing body of research investigating associations between dietary inflammatory potential, determined by the DII, and risk of a wide range of NCDs has emerged. In this narrative review, we examine the current state of the science regarding relationships between the DII and cancer, cardiometabolic, respiratory and musculoskeletal diseases, neurodevelopment, and adverse mental health outcomes. We synthesize the findings from recent studies, discuss potential underlying mechanisms, and look to the future regarding novel applications of the adult and children's DII (C-DII) scores and new avenues of investigation in this field of nutritional research.