Background/objectives: Recent long-term prospective cohort studies found inverse associations between chocolate consumption and the risk of type 2 diabetes, but provided conflicting evidence on the nature of the association among women. To assess this association in a large cohort of American women.
Subjects/methods: Multivariable Cox regression was used with the data from 92 678 postmenopausal women in the prospective Women's Health Initiative study. Chocolate intake was assessed by food frequency questionnaire. Incidence of type 2 diabetes was determined by self-report of the first treatment with oral medication or insulin.
Results: Among women free of diabetes at baseline, there were 10 804 cases, representing an incidence rate of 11.7% during 13.1 years and 1 164 498 person-years of follow-up. There was no significant linear association between long-term chocolate intake and type 2 diabetes risk, but there was significantly reduced risk at moderate levels of intake. Compared to women who ate 1 oz. of chocolate <1 time per month, those who ate this amount 1-<1.5 times per month, 1.5-<3.5 times per month, 3.5 times per month to <3 times per week and ⩾3 times per week had hazard ratios of 0.97 (95% confidence interval: 0.92, 1.04), 0.92 (0.87, 0.98), 0.93 (0.88, 0.98) and 0.98 (0.92, 1.04) (P for linear trend=0.79). There was only evidence of such inverse associations for women with below-median physical activity (P for interaction <0.0001) and those with age<65 years (P=0.01).
Conclusions: We only found an inverse association between chocolate consumption and type 2 diabetes at moderate levels of consumption in two subgroups of postmenopausal women in the Women's Health initiative cohort.