Dietary Patterns Are Associated with Lower Incidence of Type 2 Diabetes in Middle-aged Women: the Shanghai Women's Health Study

Background: Data linking risk of type 2 diabetes (T2D) and dietary patterns in Chinese populations are scarce.

Methods: A population-based prospective study of 64,191 middle-aged women in urban Shanghai, China, who were free of T2D and other chronic diseases at study recruitment, was conducted. Dietary intake, physical activity and anthropometric measurements were assessed through in-person interviews. Dietary patterns were assessed by using K-means cluster analysis. Cox regression model was used to evaluate the association of dietary patterns with the risk of T2D.

Results: We identified three dietary clusters in this population. Cluster 1 (56.3%; N = 36,159) had the highest intake of staples, cluster 2 (40.4%: N = 25,948) had the highest intake of dairy milk, and cluster 3 (2.9%; N = 1843) had the highest energy intake. Participants in cluster 2 had lower prevalence of obesity, central obesity and hypertension at baseline. Using cluster 1 as the reference, participants in cluster 2 had a lower incidence of T2D after 6.9 years of follow-up [relative risk (RR) 0.78; 95% confidence interval (CI) 0.71-0.86]. The RR for the incidence of T2D for cluster 3 compared with cluster 1 was 1.05 (95% CI 0.81-1.35). The association was not modified by age category, body mass index category, waist-to-hip ratio category or exercise participation.

Conclusions: We identified and characterized dietary patterns in middle-aged Chinese women by using cluster analysis. We identified a dietary pattern low in staple foods and high in dairy milk, which was associated with lower risk of T2D. Study of dietary patterns will help elucidate links between diet and disease, and contribute to the development of healthy eating guidelines for health promotion.