The association between the dietary inflammatory index and allergic rhinitis: a case-control study.

Background and objective: Allergic rhinitis (AR) is a common chronic inflammatory disease that significantly impacts the quality of life of patients. However, there is limited research on the relationship between the Dietary Inflammatory Index (DII) and the risk of AR. Our study aimed to assess the association between DII and AR in a sample of adults from North China. Methods: In a case-control study, we selected 166 cases of AR and 166 age- and gender-matched controls. Dietary intake was assessed using a validated food frequency questionnaire. The energy-adjusted DII (E-DII) scores were calculated based on the quantity of diet components with inflammatory or anti-inflammatory potential. We used conditional logistic regression models to examine the association between E-DII and AR. Results: Our findings indicate a positive correlation between E-DII and AR risk. After controlling for confounders, individuals in the highest E-DII tertile exhibited a 4.41-fold increased risk of AR compared to those in the lowest tertile (OR 4.41, 95% CI 2.31-8.41). Additionally, stratified analysis showed that E-DII was positively associated with AR subtype (seasonal vs. perennial), duration (≤6 years vs. >6 years), severity (mild vs. moderate-severe), and onset time (intermittent vs. persistent). Furthermore, individuals in the highest E-DII tertile had higher intake of total fat, SFA, PUFAs, and n-6 PUFAs. Conclusion: In conclusion, we realized that there is a positive association between the E-DII score and AR. The consumption of diets abundant in anti-inflammatory nutrients and low in pro-inflammatory nutrient contents is recommended as a preventative strategy against AR.

Association of the dietary inflammation index DII with the prevalence of chronic kidney disease in patients with hypertension.

BACKGROUND AND OBJECTIVE: Chronic kidney disease (CKD) is a global health concern that is frequently associated with hypertension. Inflammation is an important factor in the development of both illnesses. The Dietary Inflammation Index (DII) has evolved as a way to measure how much a diet can cause inflammation, which may impact CKD, especially in hypertensive persons. The study's goal is to investigate the link between DII and the occurrence of CKD in hypertensive individuals. METHODS: This study examined data from 22940 hypertensive patients from 1999 to 2018 of the National Health and Nutrition Examination Survey (NHANES). The DII was computed using 28 dietary components. CKD was diagnosed based on the estimated glomerular filtration rate and urine albumin-to-creatinine ratio. The link between DII and CKD was explored using sampling-weighted logistic regression and restricted cubic splines. RESULTS: Higher DII scores were shown to be strongly related with an increased risk of CKD. In the fully adjusted model, this connection remained consistent across demographic and clinical categories. CONCLUSIONS: The study found a strong association between a pro-inflammatory diet and an elevated risk of CKD in hypertensive individuals, emphasizing the potential of dietary changes in CKD management.

Influence of lifestyle patterns on depression among adults with diabetes: a mediation effect of dietary inflammatory index.

BACKGROUND: Lifestyle has become a crucial modulator in the management of diabetes and is intimately linked with the development and exacerbation of comorbid depression. The study aimed to analyze lifestyle patterns and their impact on depression in individuals with diabetes and to explore the role of the Dietary Inflammatory Index (DII) in the relationship between lifestyle patterns and depression. METHODS: Data was attained from the National Health and Nutrition Examination Survey (NHANES) between 2009 and 2020. A latent class analysis (LCA) was performed on 3,009 diabetic adults based on lifestyle behaviors. A generalised linear model (GLM) was employed to analyse the effects of different lifestyle patterns on depression. The mediation effect model was utilised to examine the relationship between lifestyle patterns, DII and Patient Health Questionnaire-9 (PHQ-9) scores. RESULTS: The cohort was divided through LCA into unhealthy lifestyle (44.53%), unhealthy but non-alcohol use (48.06%) and healthy but smoking (7.41%) groups of lifestyle behaviors, the unhealthy but non-alcohol use group was identified as a risk factor for depression (OR = 1.379, 95%CI = 1.095 ~ 1.735, P = 0.006). The DII partially mediated the relationship between the unhealthy but non-alcohol use group and PHQ-9, and fully mediated the relationship between the healthy but smoking group and PHQ-9, with effect coefficients of - 0.018 (95%CI: -0.044 ~ - 0.001) and - 0.035 (95%CI: -0.083 ~ - 0.001). CONCLUSIONS: Lifestyle patterns significantly influence the occurrence of depression among diabetes patients. The dietary inflammation plays a varying mediating role between different lifestyle patterns and depression. Restricting pro-inflammatory diets or encouraging anti-inflammatory diets, combined with the promotion of healthy lifestyle practices, may be an effective method for preventing and alleviating symptoms of depression among patients with diabetes.

Pro-inflammatory diets promote the formation of hyperuricemia.

Background: Hyperuricemia, as a very prevalent chronic metabolic disease with increasing prevalence year by year, poses a significant burden on individual patients as well as on the global health care and disease burden, and there is growing evidence that it is associated with other underlying diseases such as hypertension and cardiovascular disease. The association between hyperuricemia and dietary inflammatory index (DII) scores was investigated in this study. Methods: This study enrolled 13, 040 adult subjects (aged ≥ 20 years) from the US National Health and Nutrition Survey from 2003 to 2018. The inflammatory potential of the diet was assessed by the DII score, and logistic regression was performed to evaluate the relationship between the DII score and the development of hyperuricemia; subgroup analyses were used to discuss the influence of other factors on the relationship. Results: Participants in the other quartiles had an increased risk of hyperuricemia compared to those in the lowest quartile of DII scores. Stratification analyses stratified by body mass index (BMI), sex, hypertension, drinking, diabetes, education level and albumin-creatinine-ratio (ACR) revealed that the DII score was also associated with the risk of hyperuricemia (P<0.05). There was an interaction in subgroup analysis stratified by sex, age, and hypertension (P for interaction <0.05). The results showed a linear-like relationship between DII and hyperuricemia, with a relatively low risk of developing hyperuricemia at lower DII scores and an increased risk of developing hyperuricemia as DII scores increased. Conclusions: This study showed that the risk of hyperuricemia increased at slightly higher DII scores (i.e., with pro-inflammatory diets), but not significantly at lower levels (i.e., with anti-inflammatory diets). The contribution of the DII score to the development of hyperuricemia increased with higher scores. The relationship between inflammatory diets and hyperuricemia requires more research on inflammation, and this study alerts the public that pro-inflammatory diets may increase the risk of developing hyperuricemia.

The relationship between dietary inflammatory index scores and rheumatoid arthritis disease activity.

INTRODUCTION: Many patients diagnosed with rheumatoid arthritis (RA) report relief of symptoms after consuming certain foods. Diet plays a vital role in rheumatoid arthritis-related inflammation regulation. This study investigates the relationship between dietary inflammation index (DII) scores and RA disease activity. MATERIALS AND METHODS: Forty-one RA patients were enrolled in the study. The general inflammatory index of the diet was analyzed by recording the 24-h food consumption of the patients, and the nutrients were analyzed using the Nutrition Information Systems Package Program. Dietary inflammatory indices were calculated for each patient using the patients' macro and micronutrient intake levels. RA disease activity was assessed using the Disease Activity Score-28 (DAS-28). RESULTS: The DAS-28 score was lower in the anti-inflammatory diet group compared to the pro-inflammatory diet group (p=0.163). A weak but significant relationship was found between diet inflammation index score and DAS-28 (r=0.3468, p=0.0263). The effect of the dietary inflammatory index on the DAS-28 was 12.02%. Dietary iron, vitamin C, niacin, and magnesium intakes were statistically significantly higher in the quartile group that received an anti-inflammatory diet than in the quartile group that received a pro-inflammatory diet. The intake of some micronutrients, such as iron, zinc, magnesium, and folic acid, was significantly lower than the recommended values in all RA quartile groups. CONCLUSION: Our results suggest that reducing inflammation through the diet may have a weak but significant effect in controlling disease activity in RA patients.

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.

Dietary inflammatory index could increase the risk of sarcopenia in patients with chronic kidney disease.

Using a system that incorporates a variety of food items rather than focusing on individual components can aid in assessing the inflammatory effects of a diet on disease outcomes such as chronic kidney disease (CKD). Therefore, we decided to investigate the association between dietary inflammatory index (DII) and the risk of protein-energy wasting (PEW) and sarcopenia in patients with CKD. In this cross-sectional study, 109 patients with CKD were selected from two clinics in Shiraz, Iran. The intake of individuals' diets was recorded using a validated 168-item food frequency questionnaire. Additionally, Asian Working Group for Sarcopenia (AWGS) guidelines were utilized to evaluate muscles' strength, mass, and function. Also, four International Society of Renal Nutrition and Metabolism (ISRNM) criteria (body mass index, intake of protein, albumin, and urine creatinine) were used  to diagnose PEW. Logistic regression was used to assess the association between DII and sarcopenia as well as PEW. The results showed that the intake of saturated fatty acids, trans fatty acids, niacin, beta-carotene, and vitamin C was significantly different between lower and higher DII groups. In the univariate model, higher odds of sarcopenia was observed by each unit increase in DII (odds ratio (OR) = 1.379, 95% confidence interval (CI): 1.042-1.824) and age (OR = 1.073, 95% CI: 1.017-1.132). Additionally, in the multivariate model, the association between DII and age with odds of sarcopenia remained significant (DII: OR = 1.379, 95% CI: 1.030-1.846 and age: OR = 1.063, 95% CI: 1.007-1.121). The current study suggests the possible role of pro-inflammatory foods in worsening muscle health, specifically sarcopenia, in CKD patients. Future longitudinal studies may reveal the causative nature of these correlations.

The association between dietary inflammatory index with some cardio-metabolic risk indices among the patients with type 2 diabetes from Hoveyzeh cohort study: a cross-sectional study.

BACKGROUND: The dietary inflammatory index (DII) serves as a tool to assess the inflammatory impact of an individual's diet. This study aimed to investigate the association between DII and some cardio-metabolic risk indices among patients with T2DM. METHODS: Data from the Hoveyzeh Cohort Study, encompassing 2045 adults with T2DM, were analyzed. DII scores were calculated based on food frequency questionnaires. Anthropometric measurements and biochemical tests were performed to assess cardio-metabolic risk factors. RESULTS: Higher DII scores were positively associated with elevated triglyceride levels, triglyceride-glucose (TyG) index, lipid accumulation product (LAP), anthropometric indices including a body shape index (ABSI), body roundness index (BRI), body mass index (BMI), hip, waist circumferences (WC), and waist-to-height ratio (all Ptrend < 0.05). Notably, no significant association was observed between DII and fasting blood sugar (FBS) levels (Ptrend > 0.05). Additionally, dietary intake analysis revealed a negative correlation between DII scores and intake of fiber, fruits, vegetables, legumes, fish, seafood, dairy products, magnesium, and vitamins A, C, D, and E (all Ptrend < 0.05). Conversely, higher DII scores were associated with increased consumption of red meat, processed meat, refined cereals, potatoes, and soft drinks (all Ptrend < 0.05). CONCLUSION: This study underscores the critical link between dietary inflammation, assessed by the DII score, and a multitude of cardio-metabolic risk factors in patients with T2DM. Notably, while the study did not find a significant association between DII and fasting blood sugar levels, it identified robust associations with novel anthropometric and biochemical indices indicative of cardio-metabolic risk. These findings highlight the potential of dietary interventions as a cornerstone strategy for managing T2DM and mitigating its associated complications.

Dietary inflammatory index and its association with risk of metabolic syndrome and its components: a systematic review and Meta-analysis of Observational studies.

BACKGROUND: It is believed that the progression and development of metabolic syndrome (MetS) are associated with low-grade systemic inflammation. Several studies have suggested that the Dietary Inflammatory Index (DII), which estimates the inflammatory potential of diets, is associated with MetS. This systematic review and meta-analysis aimed to determine the relationships between DII and the MetS and its components. METHODS: Relevant articles published in English from inception to May 2024 were identified by searching electronic databases including PubMed, Scopus, and Web of Science. We included studies that reported the odds ratio (OR), relative risk (RR), or hazard ratio for the association of DII with the MetS and its components. Effect sizes were pooled using a random effects model. RESULTS: A total of three prospective studies and 22 cross-sectional studies were included in this meta-analysis. The results showed that pro-inflammatory diets were significantly associated with an increased risk of MetS in cohort studies (RR: 1.33; 95% confidence interval [CI]: 1.19-1.48) and cross-sectional studies (OR:1.24; 95% CI: 1.11-1.38). Meta-analysis of cross-sectional studies showed that a higher DII score was significantly associated with higher odds of hypertension (OR = 1.19; 95% CI = 1.10-1.28) and hyperglycemia (OR = 1.18; CI = 1.06-1.32). The pooled OR comparing the highest versus lowest category of DII with the odds of abdominal obesity and hypertriglyceridemia was significant only after adjustment for covariates. CONCLUSIONS: In general, higher DII is associated with a higher risk of MetS and some of its components. Based on the findings, dietary interventions should be considered for preventing MetS from the inflammatory perspective.

Association of Pro-Inflammatory Diet, Smoking, and Alcohol Consumption with Bladder Cancer: Evidence from Case-Control and NHANES Studies from 1999 to 2020.

BACKGROUND AND PURPOSE: Diet might be a modifiable factor in preventing cancer by modulating inflammation. This study aims to explore the association between the dietary inflammatory index (DII) score and the risk of bladder cancer (BC). METHODS: A total of 112 BC patients and 292 control subjects were enrolled in a case-control trial. Additionally, we tracked a total of 109 BC patients and 319 controls, whose propensity scores were obtained from the Nutrition Examination Survey (NHANES) database spanning from 1999 to 2020. The baseline index and dietary intake data were assessed using a food frequency questionnaire (FFQ). DII scores were calculated based on the dietary intake of 20 nutrients obtained from participants and categorized into four groups. The association between the inflammatory potential of the diet and BC risk was investigated using multivariate odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: High DII scores were associated with a pro-inflammatory diet and a higher risk of BC, with higher DII scores positively associated with a higher risk of BC (quartiles 4 vs. 1, ORs 4.89, 95% CIs 2.09-11.25 p < 0.001). Specifically, this might promote BC development by inducing oxidative stress and affecting DNA repair mechanisms. This result was consistent with the NHANES findings (quartiles 4 vs. 1, ORs 2.69, 95% CIs 1.25-5.77, p = 0.006) and further supported the association of pro-inflammatory diet and lifestyle factors with the risk of BC. CONCLUSIONS: Diets with the highest pro-inflammatory potential were associated with an increased risk of BC. By adjusting lifestyle factors, individuals might effectively lower their DII, thereby reducing the risk of developing BC. The results are consistent with the NHANES cohort.

The Association of Dietary Inflammatory Index and Cognitive Function in Iranian Elders.

BACKGROUND: Cognitive impairment is amongst the most substantial mental health problems in elderly people, and inflammation is an underlying mechanism for cognitive impairment. The dietary inflammatory index (DII®) reflects the overall inflammatory potential of individuals' diets. The current study aimed to assess the relationship between the DII and cognitive function among the Iranian old population. METHODS: This cross-sectional study was conducted on 221 subjects≥65 years old in healthcare centers in five socioeconomically distinct districts of Tehran, Iran. Dietary intake data were obtained using a validated food frequency questionnaire (FFQ). Energy-adjusted-DII (E-DIITM) scores were calculated for each participant according to a total of 35 food parameters, which were available from the FFQ. Mini mental state examination (MMSE), a brief screening questionnaire was used to assess cognitive function. RESULTS: E-DII scores were not significantly associated with cognitive function, both in the crude model (ß=-0.04, p-value=0.82) and after adjusting for potential confounders (ß=0.22, pvalue= 0.14). Additionally, in the unadjusted model, individuals in the highest tertile of E-DII score had increased odds of mild cognitive impairment (OR=1.13, p-trend=0.01) compared to those older adults in the lowest tertile of E-DII score. However, after controlling for potential confounders, these relationships faded (AOR=1.46, p-trend=0.12). CONCLUSION: The findings of the present study showed no significant relationship between E- DII and cognitive function among the Iranian elderly. Future prospective studies should be undertaken to explore the association between diet-associated inflammation and cognitive decline in the elderly.

Association of the dietary inflammatory index with complicated diabetic kidney disease in people with diabetes mellitus: evidence from NHANES 2009-2018.

AIMS: Diabetic kidney disease (DKD) significantly impairs quality of life in individuals with diabetes mellitus (DM). The influence of the Dietary Inflammatory Index (DII) on DKD, which is associated with adverse health outcomes, is not well-understood. METHODS: We analyzed 2712 subjects from the National Health and Nutrition Examination Survey (NHANES) spanning 2011-2018, aiming to elucidate the relationship between DII and DKD. RESULTS: DKD was diagnosed in 1016 participants (37.46%). Elevated DII levels were significantly associated with an increased DKD risk, as evidenced by multivariate logistic regression (Odds Ratio [OR] = 1.40, 95% Confidence Interval [CI] 1.12-1.75, P < 0.05). Further analysis after adjusting for covariates highlighted a notable non-linear correlation between DII and DKD risk, at DII values below 0.45, the risk of DKD increases with higher DII levels, whereas it stabilizes beyond this point. Subgroup analysis additionally revealed that diabetic men have a significantly higher DKD risk compared to women (P < 0.05). CONCLUSION: Our study indicates a pronounced link between higher DII scores and increased risk of DKD among DM patients. These findings underscore the paramount importance of dietary management in DM treatment, stressing the need for interventions focused on reducing dietary inflammation to decelerate DKD progression.

Association of dietary inflammatory index with immune-inflammatory biomarkers in rheumatoid arthritis patients: results from NHANES 1999-2018.

Background: Synovial inflammation is the main reason for joint damage in patients with rheumatoid arthritis (RA). Diet is recognized as one of the therapeutic strategies to control the inflammatory activity in RA. However, few studies have investigated the association between diet and immune-inflammatory biomarkers in RA patients. Our study aims to examine the correlation between dietary inflammatory potential and systemic immune-inflammation Index (SII), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), and lymphocyte-monocyte ratio (LMR) in the RA population. Materials and methods: The National Health and Nutrition Examination Survey (NHANES) was the data source utilized in this study, spanning from 1999 to 2018. The study encompassed 2,500 RA participants in total. The dietary inflammatory potential was calculated by the dietary inflammation index (DII) score based on dietary recall interviews. The generalized multiple linear regression analyses were used to evaluate the relationship between DII and immune-inflammatory markers. Furthermore, subgroup analyses and restricted cubic spline models were performed. Results: After full adjustments, there were significant positive correlations between DII levels and SII/NLR in RA patients (SII, ß: 14.82, 95% CI: 5.14-24.50, p = 0.003; NLR, ß: 0.04, 95% CI: 0.01-0.08, p = 0.005). It was noteworthy that inconsistent results were observed in the association between DII and SII as well as NLR in subgroups of red blood cell levels (Interaction p-value <0.001). Conclusion: Pro-inflammatory dietary status in the RA population is significantly positively correlated with SII and NLR, influenced by variations in red blood cell levels.

Dietary inflammatory index and lower glomerular filtration rate in Mexican adults.

We hypothesized that higher scores on the dietary inflammatory index (DII) would be associated with a lower glomerular filtration rate (GFR). This cross-sectional study included 2098 participants from Mexican Teachers Cohort Study, the Health Workers Cohort Study, and the Comitán Study belonging to the RenMex consortium. Energy-adjusted DII scores were estimated using a semi-quantitative food frequency questionnaire (FFQ). eGFR was estimated by the CKD Epidemiology Collaboration equation. Quantile regression models and ordered regression models were estimated to assess the associations of interest. Median age of study participants was 47 years, median eGFR was 102.9 mL/min/1.73m2, and the median energy-adjusted DII was 0.89 (range, -2.25, +4.86). The median eGFR was lower in participants in the highest percentile of DII compared to those in the lowest percentile (103.8 vs 101.4). We found that continuous and categorical energy-adjusted DII scores were associated with lower eGFR, especially at the lower percentiles. In adjusted ordered logistic regression, we found that the highest DII category was associated with 1.80 times the odds of belonging to the mildly decreased eGFR category or moderately decreased eGFR category compared lowest DII category (OR: 1.80, 95%CI 1.35, 2.40). A high DII score was associated with a lower eGFR among the Mexican population. Additional studies are crucial to validate these findings and explore potential strategies to reduce the consumption of pro-inflammatory foods as a preventive approach for chronic kidney disease (CKD).

A systematic review and meta-analysis of Dietary Inflammatory Index and the likelihood of multiple sclerosis/ demyelinating autoimmune disease.

Diet and inflammation may contribute to the development of multiple sclerosis (MS). The aim of this systematic review and meta-analysis was to assess the association between proinflammatory diet, as estimated by the Dietary Inflammatory Index (DII®), and the likelihood of developing MS or other demyelinating autoimmune diseases. A systematic search was performed of search engines and databases (PubMed, ISI Web of Sciences, Scopus, and Embase) to identify relevant studies before 10th June 2023. The search identified 182 potential studies, from which 39 full-text articles were screened for relevance. Five articles with case-control design (n = 4,322, intervention group: 1714; control group: 2608) met the study inclusion criteria. The exposure variable was DII, with studies using two distinct models: quartile-based comparisons of DII and assessment of continuous DII. The meta-analysis of high versus low quartiles of DII with four effect sizes showed a significant association with MS/demyelinating autoimmune disease likelihood, with an odds ratio (OR) of 3.26 (95% confidence interval (CI) 1.16, 9.10). The meta-analysis of four studies with DII fit as a continuous variable showed a 31% increased likelihood of MS per unit increment; which was not statistically significant at the nominal alpha equals 0.05 (OR 1.31; 95% CI 0.95, 1.81). In conclusion, this systematic review and meta-analysis provides evidence of a positive association between higher DII scores with the likelihood of developing MS, highlighting that diet-induced inflammation could play a role in MS or other demyelinating autoimmune diseases risk.

Dietary inflammatory index, mediating biomarkers and incident frailty in Chinese community-dwelling older adults.

OBJECTIVES: Diet can modulate systemic inflammation, while inflammation is a critical contributory factor of frailty. However, longitudinal data on the association between dietary inflammatory index (DII) and frailty are limited, and the intermediate mechanisms remain unclear. This study aimed to examine the association between DII and incident frailty and the potential mediating roles of frailty-related biomarkers. DESIGN: Prospective cohort study. SETTING: The Mr. OS and Ms. OS (Hong Kong) study. PARTICIPANTS: A total of 3,035 community-dwelling men and women aged above 65 years without frailty at baseline were included. MEASUREMENTS: DII scores were calculated using the locally validated food frequency questionnaire. Incident frailty at year four was defined using the Fried frailty phenotype. Logistic regression was used to examine the association between DII and frailty onset. Mediation analysis was used to explore the mediating roles of frailty-related biomarkers in the DII-frailty association. RESULTS: During four years of follow-up, 208 individuals developed frailty. Compared with the lowest tertile of DII, the highest tertile was associated with an increased risk of incident frailty (OR: 1.82; 95% CI: 1.17-2.82; p = 0.008) after adjustment for relevant confounders. The DII-frailty association was significant in men but not in women. Furthermore, increasing serum homocysteine, decreasing serum folate, and reducing estimated glomerular filtration rate (eGFR) mediated 11.6%, 7.1%, and 9.6 % of the total relation between DII and frailty onset, respectively. CONCLUSION: In this cohort study, a pro-inflammatory diet was associated with a higher risk of frailty onset, mediated by homocysteine, folate, and renal function.

Dietary inflammatory index (DII) and sleep quality, duration, and timing: A systematic review.

Sleep has strong inflammatory underpinnings and diet is one of the primary determinants of systemic inflammation. A systematic literature review was conducted to synthesize current research associating dietary inflammatory potential, as measured by the dietary inflammatory index (DII®) or the energy-adjusted DII (E-DII™) and sleep quality and duration. The National Library of Medicine (Medline), Web of Science, and PsycInfo databases were searched through March 2023. Studies must have used the DII/E-DII as the independent variable and sleep outcomes as dependent variables. Study characteristics, based on STROBE guidelines, were scored based on the presence of the recommendation. Out of the initial 14 studies identified, a total of 12 studies were included for data synthesis. In all 12 studies, more anti-inflammatory diets (i.e., low DII/E-DII scores) were associated with better sleep in at least one sleep domain (most often sleep efficiency and wake-after-sleep-onset). Among those studies with more rigorous diet and sleep measurements, such as dietary recalls and actigraphy, associations between DII/E-DII and sleep outcomes were stronger and more consistent compared to studies using primarily subjective assessments. More rigorous measurement of diet and sleep, especially those relating to sleep stage structure, should be considered in future studies with prospective designs.

The Association Between Diets With High Inflammatory Potential and Sleep Quality and Its Parameters: A Systematic Review.

CONTEXT: Dietary components or its overall properties can influence an individual's sleep status. OBJECTIVE: The aim for this study was to critically search, appraise, and synthesize research evidence on the association between dietary inflammatory index (DII) and sleep quality and its parameters. DATA SOURCES: Original published studies on adults were obtained from the PubMed, SCOPUS, ScienceDirect, Cochrane Library, and Google Scholar databases. DATA EXTRACTION: The search was conducted without date limitation until April 2023. Duplicated and irrelevant investigations were screened out, and the results of the remaining articles were descriptively summarized, then critically appraised and analyzed. Possible mechanistic pathways regarding diet, systemic inflammation, and sleep status were discussed. DATA ANALYSIS: Of the 102 studies searched, 23 articles (n = 4 cohort studies, 18 cross-sectional studies, and 1 intervention study) were included in the final review. The association between DII and sleep status was investigated subjectively in 21 studies and objectively in 6 studies. The main studied sleep outcomes were sleep quality, duration, latency, efficiency, apnea, disturbances, the use of sleeping medications, daytime dysfunctions, wakefulness after sleep onset, and rapid eye movement. CONCLUSIONS: According to most of the evidence, DII may not be related to overall sleep quality, sleep duration, latency, efficiency, and the use of sleeping medications. The evidence of positive association was greater between a high DII score (pro-inflammatory diet) with daytime dysfunctions, wakefulness after sleep onset, and sleep apnea. There is insufficient evidence to make any conclusion regarding sleep disturbances and rapid eye movement.

Comparison of dietary inflammatory index and total antioxidant capacities of familial Mediterranean fever and healthy adolescents.

BACKGROUND: Although it is known that consumed nutrition affects inflammatory load, and total antioxidant capacity (TAC) is affected by inflammatory diseases and consumed nutrients, these conditions have not been adequately investigated in adolescents with familial Mediterranean fever (FMF). Therefore, this study aimed to compare the dietary inflammatory index (DII), TAC and total oxidant capacity (TOC) of adolescents with FMF and healthy adolescents. METHODS: This case-controlled study consisted of 180 adolescents (aged 10-19) divided into FMF (n = 135) and control (n = 45 healthy) groups. Study data were collected face-to-face using a survey on demographic characteristics, anthropometric measurements, biochemical biomarkers and 3-day dietary recall to calculate DII scores. RESULTS: FMF group had lower DII score than controls (2.12 ± 0.78 vs. 2.33 ± 1.06, p < 0.05). In addition, they had higher C-reactive protein (CRP), TOC (p < 0.05) and oxidative stress index (OSI) (p = 0.51) than the control group. On the contrary, the control group had significantly higher tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) values (p < 0.05). There was a positive correlation between DII scores and TNF-α in the FMF group (p < 0.05). The control group had significantly higher energy, protein, medium-chain fatty acids (MCT) and saturated fatty acids (SFA) intake than FMF (p < 0.05). On the contrary, the FMF group had significantly higher vitamin A and D, niacin and zinc intake (p < 0.05). CONCLUSION: The results showed that adolescents with FMF had lower DII and higher OSI than healthy adolescents. It may be beneficial for adolescents with FMF to consume a diet containing anti-inflammatory nutrients to maintain normal growth and development and to prevent symptoms and complications of the disease.

The association between dietary inflammatory index and risk of neuromyelitis optica spectrum disorder: a case-control study.

BACKGROUND AND AIM: Neuromyelitis optica spectrum disorder (NMOSD) is a severe and rare inflammatory disease affecting the central nervous system through optic neuritis and transverse myelitis. Present study aimed to investigate the association between dietary inflammatory index (DII) and risk of NMOSD. METHODS: In this case-control study, 30 NMOSD cases and 90 aged matched healthy individuals were recruited. Habitual dietary intakes were assessed by a validated 168-item food frequency questionnaire to calculate the DII score. A multiple adjusted regression was used to determine the odd ratio (OR) of NMOSD across DII tertiles. The Residual method was applied to adjust the energy intake. RESULTS: Participants in the top of DII tertile were more likely to have NMOSD in the crude model compared to those with the lowest one (OR: 4.18; 95%CI: 1.43-12.21). It was the case when multivariable confounders were considered in adjustment model I (OR: 3.98; 95%CI: 1.34-11.82) and II (OR: 4.43; 95%CI: 1.36-14.38), such that, individuals with a greater DII score had 3.98 and 4.43-time higher risk of NMOSD in model I and II, respectively. CONCLUSION: The Present study suggests that greater adherence to a pro-inflammatory diet may be associated with an increased risk of NMOSD.