Nut consumption is associated with lower incidence of type 2 diabetes: The Tehran Lipid and Glucose Study

Abstract

Aim: Nuts are rich in unsaturated fatty acids as well as other bioactive constituents. The present study investigated the association between nut consumption and the incidence of type 2 diabetes mellitus (T2DM) in a Middle Eastern population.

Methods: The study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS), in which 1984 participants (920 men and 1064 women) free of DM, aged≥20 years, were followed from phase III (2005-2008) to phase V (2011-2014). Dietary data were obtained from valid and reliable food-frequency questionnaires at baseline. Using multiple logistic regression, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated, with adjustments for age, gender, BMI, serum cholesterol and triglycerides, smoking and energy intake.

Results: Study participants' means±SD of age and of BMI were 40.1±13.1 years and 27.0±4.8kg/m², respectively. The median±SE of their total daily consumption of nuts was 1.19±0.11 servings. After 6.2±0.7 years of follow-up, 150 cases of T2DM were confirmed. On comparing those who consumed ≥4 servings/week with those who consumed <1 serving/week, the age-/energy-adjusted OR of incident T2DM for total nut consumption was 0.64 (95% CI: 0.36-1.12; P for trend = 0.03). In a fully adjusted model, nut consumption was associated with a lower risk of T2DM, and the ORs (95% CIs) of risk for those consuming 2-3.99 and ≥4 servings/week of nuts were 0.51 (0.26-0.97) and 0.47 (0.25-0.90), respectively, compared with those consuming <1 serving/week (P<0.001 for trend).

Conclusion: Our findings suggest that consuming ≥4 servings/week of nuts reduced the risk of T2DM compared with <1 serving/week.

Keywords: Incidence; Nuts; Type 2 diabetes.