The association between dietary inflammatory index (DII) scores and c-reactive protein (CRP) and nonalcoholic fatty liver disease (NAFLD) in a general population cohort.

BACKGROUND AND AIMS: Although there is extensive literature showing the ability of the dietary inflammation index (DII®) to predict concentrations of plasma inflammatory markers, few studies are testing the association between DII scores and nonalcoholic fatty liver disease (NAFLD). Considering the high prevalence of NAFLD and its complications, we conducted a validation study of DII scores and examined its association with NAFLD in the general adult population of Iran. METHODS: This cross-sectional study was conducted on 3110 adult participants in the Amol Cohort Study (AmolCS) who underwent abdominal ultrasonography to diagnose NAFLD. DII and energy-adjusted DII (E-DII™) scores were computed using data from a valid semi-quantitative 168-item food frequency questionnaire (FFQ). Multivariable logistic regression adjusting for socio-demographic, lifestyle, and health-related factors was used to assess association. RESULTS: The EDII was associated with CRP inflammatory biomarker. Participants in the highest, i.e., most pro-inflammatory tertile had the highest odds of NAFLD by ultrasound in all models [fully adjusted model: OR (95 % CI) tertile3vs.1:1.54 (1.05-2.05); Ptrend = 0.04, and 1.63 (1.19-2.21); Ptrend = 0.03 in women and men, respectively]. The highest tertile had the highest OR for NAFLD by fatty liver index (FLI) only in men [fully adjusted model OR (95 % CI) tertile3vs.1: 1.77 (1.15-2.71); Ptrend = 0.01]. Similar results were also obtained for NAFLD by hepatic steatosis index (HSI) in women [fully adjusted model: OR (95 % CI) tertile3vs.1: 1.70 (1.12-2.58); Ptrend = 0.03]. The results of the fully adjusted multivariable model of liver markers and NAFLD status, stratified by gender and abdominal obesity, revealed that the highest tertiles had the highest OR for NAFLD by ultrasound and NAFLD by FLI only in men without abdominal obesity [fully adjusted model: OR (95 % CI) tertile3vs.1: 1.83 (1.17-2.84); Ptrend = 0.03, and, respectively]. NAFLD by FLI tended to increase strongly with tertile E-DII scores in men without abdominal obesity in crude and three adjusted models [full-adjusted model: OR (95 % CI) tertile3vs.1: 3.64 (1.56-8.46); Ptrend = 0.005]. By contrast, women with abdominal obesity in the highest tertile had the highest OR for NAFLD by ultrasound in all models [full-adjusted model: OR (95 % CI) tertile3vs.1: 1.67 (1.07-2.62); Ptrend = 0.02]. CONCLUSIONS: Our results suggest that diet plays a role in regulating inflammation. Additionally, we observed an inflammatory diet predicts the risk of NAFLD in Iranian adults. However, longitudinal studies are required in order to further substantiate the utility of the DII in the development of more effective dietary interventions among populations at risk of chronic disease.

Dietary Acid Load (DAL), Glycated Hemoglobin A1c (HbA1c), and Metabolic Syndrome (MeS) Mediate the Association of the Adherence to the Dietary Approaches to Stopping Hypertension (DASH) and Mediterranean Diet (MeD) With Nonalcoholic Fatty Liver Disease.

The study aimed to investigate the association of adults adhering to Dietary Approaches to Stop Hypertension (DASH) and Mediterranean diet (MeD) with nonalcoholic fatty liver disease (NAFLD) using structural equation modeling (SEM) in Iran. In this population-based cross-sectional study, 3,220 adults (44.65% female) aged ≥18 years were selected from the Amol Cohort Study (AmolCS). The dietary intakes were assessed by a validated 168-item semi-quantitative food-frequency questionnaire (FFQ). Residual method energy adjustment of MeD and DASH scores were calculated. Demographic characteristics and anthropometric and laboratory measurements were collected. NAFLD was diagnosed by an expert radiologist via ultrasound sonography. Based on the primary hypothesis, DASH, MeD, and NAFLD were fitted into models. Metabolic syndrome (MeS) as a potential risk factor directly affected NAFLD risk in all these models. In both genders, the higher adherence to DASH negatively affected NAFLD risk indirectly through the two following paths. (1) Dietary acid load (DAL) and metabolic syndrome (2) DAL and hemoglobin A1c (HbA1c). In addition, the higher DAL positively affected NAFLD risk among male participants indirectly via increasing HbA1c level and MeS (from DAL to HbA1c: ß = 0.07, P < 0.001; from HbA1c to MeS: ß = 0.10, P < 0.001). Similarly, in both genders, the relationship between MeD and NAFLD was mediated through (1) DAL, HbA1c, and MeS and (2) DAL and MeS. Further, among male participants, the MeD and NAFLD risk were also associated via the mediators of HbA1c and MeS. In female participants, the higher MeD score was directly associated with a reduction of NAFLD risk (ß = -0.07, P = 0.008). The present study found three important mediators, including DAL, HbA1c, and MeS, in the association of DASH and MeD scores with NAFLD risk. Preventive and therapeutic interventions should target the mediators, including DAL, HbA1c, MeS, and its components, to reduce NAFLD incidence in the general population.

Favorable association between Mediterranean diet (MeD) and DASH with NAFLD among Iranian adults of the Amol Cohort Study (AmolCS).

Nonalcoholic fatty liver disease (NAFLD) is an emerging cause of chronic liver diseases and a major health problem worldwide. Dietary patterns may play a critical role in controlling and preventing this disease, but the available evidence is scarce. The current study aims to ascertain the association of adherence to the Dietary Approach to Stop Hypertension (DASH) diet and Mediterranean diet (MeD) with nonalcoholic fatty liver disease (NAFLD) among Iranian adults of the Amol Cohort Study (AmolCS). In a cross-sectional analysis among 3220 adults (55.3% men), age ≥ 18 years (46.96 ± 14.67), we measured usual dietary intake with a validated food frequency questionnaire (FFQ) and then calculated dietary pattern scores for DASH and MeD. Sociodemographic and lifestyle factors were collected by a structured questionnaire. The presence and degree of NAFLD were also determined by abdominal sonography. Multiple regression models were used to estimate NAFLD odds across tertiles of DASH and Mediterranean dietary scores. Dietary DASH and Mediterranean components were adjusted for total energy intake, based on the residual methods. After adjusting for multiple potential confounders, we found an inverse association of DASH and MeD with NAFLD (Ptrend = 0.02, and Ptrend = 0.002, respectively). Those in the highest tertiles of adherence to the DASH and MeD had the lowest risk for NAFLD (OR = 0.80, 95%CI = 0.66-0.96, OR = 0.64, 95%CI = 0.52-0.78, respectively). The results of logistic analysis of MeD, stratified by gender and abdominal obesity, revealed the favorable association was more pronounced in women (OR = 0.42, 95%CI = 0.29-0.61, Ptrend = 0.004), and in participants with or without abdominal obesity (OR = 0.62, 95% CI = 0.47-0.81, Ptrend = 0.03, OR = 0.64, 95%CI = 0.475-0.91, Ptrend = 0.04, respectively). Similar results were obtained for the adherence to DASH diet score with the prevalence of NAFLD patients with abdominal obesity (OR = 0.75, 95% CI = 0.57-0.97, Ptrend = 0.04). The findings suggested the favorable association between DASH and MeD with NAFLD in Iranian adults, especially women and subjects with or without abdominal obesity. Further prospective investigations are needed to confirm the integrity of our findings.

Fatty acid quality and quantity of diet and risk of type 2 diabetes in adults: Tehran Lipid and Glucose Study.

AIM: Studies suggest that fatty acid intake may be an important determinant of type 2 diabetes mellitus (T2DM). This study aims to prospectively examine the association between fatty acid quantity and quality with risk of T2DM in adults. METHODS: In this community-based prospective sample, 2139 adults, free of T2DM, aged 20-70y-old were followed for a median of 5.8 y. Diet information was collected with the use of a validated questionnaire at baseline. Cox regression and 95% confidence intervals (CI), adjusted for age, diabetes risk score (DRS), and dietary intakes of energy, fiber and magnesium, were used to evaluate the association of fatty acid intakes with incident T2DM. RESULTS: During follow-up, we identified 143 incident T2D cases. In multivariable analyses, when extreme quintiles were compared, cholesterol (HR = 0.40; 95% CI: 0.20-0.82; P-trend, 0.02), monounsaturated fatty acids (HR = 0.30; 95% CI: 0.13-0.70; P-trend, 0.02), polyunsaturated fatty acids (HR = 0.45; 95% CI: 0.24-0.93 P-trend = 0.04) and ω-3 fatty acids (HR = 0.55; 95% CI: 0.31-0.88; P-trend = 0.02) were associated with T2DM. The ratio of ω-6 to total ω-3 intake was associated with a higher risk of T2D (HR = 1.65; 95% CI: 1.05-2.86; P-trend, 0.04). We also found positive associations between the ratios of total fat to ω-3 (HR = 1.65; 95% CI: 1.02-2.46; P-trend = 0.05). CONCLUSIONS: Our findings indicate that diets with high cholesterol, monounsaturated, polyunsaturated and ω-3 fatty acids are associated with a lower risk of T2DM. Also the ratios of ω-6/ω-3 and total fat/ω-3 were positively associated with T2DM.

Dietary Protein and Amino Acid Profiles in Relation to Risk of Dysglycemia: Findings from a Prospective Population-Based Study.

Considering the limited knowledge on the effects of dietary amino acid intake on dysglycemia, we assessed the possible association of dietary protein and amino acid patterns with the risk of pre-diabetes in a prospective population-based study. Participants without diabetes and pre-diabetes (n = 1878) were recruited from the Tehran Lipid and Glucose Study and were followed for a mean of 5.8 years. Their dietary protein and amino acid intakes were assessed at baseline (2006-2008); demographic, lifestyle, and biochemical variables were evaluated at baseline and in follow-up examinations. Pre-diabetes was defined according to the American Diabetes Association criteria. Multivariate Cox proportional hazard regression models, adjusted for potential confounders, were used to estimate the risk of pre-diabetes across tertiles of dietary protein and amino acid pattern scores. The mean age of the participants (44.9% men) was 38.3 ± 12.7 years at baseline. Three major amino acid patterns were characterized: (1) higher loads of lysine, methionine, valine, aspartic acids, tyrosine, threonine, isoleucine, leucine, alanine, histidine, and serine; (2) higher loads of glycine, cysteine, arginine, and tryptophan; and (3) higher loads of proline and glutamic acid. Dietary total protein intake Hazard Ratio (HR) = 1.13, 95% Confidence Interval (CI) = 0.92-1.38 and HR = 1.00, 95% CI = 0.81-1.23, in the second and third tertile, respectively) was not related to the development of pre-diabetes. The highest score of second dietary amino acid pattern tended to be associated with a decreased risk of pre-diabetes (HR = 0.81, 95% CI = 0.65-1.01), whereas the third pattern was related to an increased risk in the fully adjusted model (HR = 1.24, 95% CI = 1.02-1.52; p for trend = 0.05). These novel data suggest that the amino acid composition of an individual's diet may modify their risk of pre-diabetes.