Relation of dietary insulin index and dietary insulin load to metabolic syndrome depending on the lifestyle factors: Tehran lipid and glucose study

Insulinemic potential of diet and the risk of type 2 diabetes: a meta-analysis and systematic review

BACKGROUND

The possible role of the insulinemic potential of diet in the etiology of type 2 diabetes (T2D) has recently received significant attention in observational studies. This meta-analysis aimed to synthesize available evidence and quantify the potential association between the empirical dietary index for hyperinsulinemia (EDIH) score and T2D risk.

METHODS

Various electronic databases, including Scopus, PubMed, and Web of Science, were comprehensively searched up to January 2024 using related keywords to identify relevant studies. The hazard ratios (HR) or odds ratios were extracted from eligible cohort studies, and a random-effects model with an inverse variance weighting method was used to calculate the pooled effect size, which was expressed as HR.

RESULTS

The analysis included six cohort studies (four publications), with sample sizes ranging from 3,732 to 90,786 individuals aged 20 to 79 years. During follow-up periods of 5 to over 20 years, 31,284 T2D incidents were identified. The pooled results showed that a higher EDIH score was associated with an increased risk of T2D incidence (HR: 1.47; 95%CI 1.21-1.77; I2 = 91.3%). Significant publication bias was observed in the present meta-analysis (P = 0.020). Geographical region and follow-up period can be as sources of heterogeneity (Pheterogeneity <0.001).

CONCLUSION

Our meta-analysis of observational studies suggested that a diet with a higher EDIH score may be associated with an increased risk of incidence of T2D.

The Application of the Food Insulin Index in the Prevention and Management of Insulin Resistance and Diabetes: A Scoping Review

The food insulin index (FII) is a novel algorithm used to determine insulin responses of carbohydrates, proteins, and fats. This scoping review aimed to provide an overview of all scientifically relevant information presented on the application of the FII in the prevention and management of insulin resistance and diabetes. The Arksey and O'Malley framework and the PRISMA Extension for Scoping Reviews 22-item checklist were used to ensure that all areas were covered in the scoping review. Our search identified 394 articles, of which 25 articles were included. Three main themes emerged from the included articles: 1. the association of FII with the development of metabolic syndrome, insulin resistance, and diabetes, 2. the comparison of FII with carbohydrate counting (CC) for the prediction of postprandial insulin response, and 3. the effect of metabolic status on the FII. Studies indicated that the FII can predict postprandial insulin response more accurately than CC, and that a high DII and DIL diet is associated with the development of metabolic syndrome, insulin resistance, and diabetes. The FII could be a valuable tool to use in the prevention and management of T1DM, insulin resistance, and T2DM, but more research is needed in this field.

Dietary insulin index, dietary insulin load and dietary patterns and the risk of metabolic syndrome in Hoveyzeh Cohort Study

Postprandial insulin secretion has been associated with metabolic disorders such as hyperlipidemia and type 2 diabetes. Therefore, we aimed to explore the relationship between dietary insulin indices and dietary pattern with the risk of Metabolic Syndrome (MetS). The participants of the present cross-sectional study were included among the individuals who participated in the Hoveyzeh Cohort Study (HCS). A total of 3905 Iranian adults, aged 35-70 years, are included in the current analysis. The Food Frequency Questionnaire (FFQ) is used to calculate the dietary Insulin Index (DII), Insulin Load (DIL), and dietary pattern. Dietary pattern was derived using Reduced-Rank Regression (RRR) based on intake of protein (g/day), fiber (g/day), fat (g/day), magnesium (mg/day), and dietary insulin index were considered as response variables. The Generalized Linear Model was used to obtain the odds ratio (OR) and 95% confidence interval (CI) for MetS based on gender, while considering quartiles of DIL, DII scores, and dietary pattern, adjusted for potential confounders. The mean ± SD of age and BMI of the participants in the top quartile of DIL were 45.72 ± 8.05 years and 28.25 ± 5.02 kg/m2, respectively. The mean ± SD of DII was 40.53 ± 4.06 and the mean ± SD of DIL was 117,986.1 ± 30,714.06. A significant positive association was observed between DIL and MetS in women after adjusting for confounding factors (OR: 1.51; 95% CI 1.16; 1.96). No significant association was seen between DIL, DII, and MetS among men. A derived dietary pattern characterized by high intakes of fruits, sugar, sweet deserts, Whole Grains, and dairy was associated with an increased risk of MetS in adjusted model2 among women (OR: 1.41; 95% CI 1.13; 1.75) and men in the same model (OR: 2.09; 95% CI 1.35; 3.21).However, the final model was significant just for men (OR: 2.08; 95% CI 1.35; 3.21) and not for women (OR: 1.24; 95% CI 0.96; 1.60). Our findings showed that adherence to a diet with a high insulin load can increase the risk of MetS in women. In addition, a derived dietary pattern by RRR indicated that a diet rich in fruits, sugar, sweet deserts, whole Grains, and dairy is related to increased risk of MetS in both men and women.

Association between dietary insulin index and load with brain derived neurotrophic factor, adropin and metabolic health status in Iranian adults

The associations of high potential insulinogenic foods with metabolic health (MH) status and brain-derived neurotrophic factor (BDNF) and adropin were not investigated quite enough. We examined the relationship between dietary insulin load (DIL) and dietary insulin index (DII) with MH and serum levels of BDNF and adropin among Iranian adults. This cross-sectional investigation accomplished among 527 Iranian middle-aged adults (54.3% men). Dietary information was obtained by a validated food frequency questionnaire. Anthropometric indices and blood pressure were assessed. For measuring lipid and glycemic profile and serum levels of BDNF and adropin, blood samples were assembled after 12 h of fasting. MH was defined based on lipid and glycemic profile, high blood pressure, insulin resistance and chronic inflammation. After adjustments all confounders, participants in the highest tertile of DII compared to the lowest one had a 115% increased odds for metabolic unhealthy (MU) profile (ORT3 vs. T1 = 2.15, 95% CI 1.03-4.49). However, DIL was not related to MU. Higher DII was additionally associated with high blood pressure, in maximally-adjusted model (ORT3 vs. T1 = 3.57, 95% CI 1.61-7.92). Moreover, moderate DIL was significantly associated with hypertriglyceridemia (ORT2 vs. T1 = 2.56, 95% CI 1.01-6.45). Each tertile increase in DII or DIL was not significantly associated with serum BDNF or adropin values. Greater DII was associated with higher chance of MU and hypertension in Iranian adults; but no association was found between DIL and metabolic health. DIL or DII was not related to circulating BDNF or adropin. To confirm these findings, additional prospective investigations are required.