Healthy Eating and Type 2 Diabetes in High-risk Populations
The Effects of Dietary Patterns in Women with History of Gestational Diabetes
Though much is known about the inverse association between a healthy diet and risk of type 2 diabetes mellitus (T2DM) in the general population, a study explored whether these benefits extend to women with a history gestational diabetes mellitus (GDM), since these women have a heightened risk of developing T2DM following their pregnancy.
The study, “Healthful dietary patterns and type 2 diabetes mellitus risk among women with a history of gestational diabetes mellitus,” was published online ahead of print in September 2012 in the Archives of Internal Medicine. The study authors examined data on 4,413 women from the Nurses’ Health Study II cohort who had a history of GDM. Follow-ups with the women were conducted between 1991 and 2005.
To examine women’s eating habits, the researchers used a food-frequency questionnaire to calculate dietary pattern adherence scores based on 3 diet patterns: the alternate Mediterranean diet (aMED), the alternate Healthy Eating Index (aHEI), and the Dietary Approaches to Stop Hypertension (DASH) plan. The researchers relied on multivariable Cox proportional hazards models to estimate the relative risk of developing T2DM following GDM, based on the women’s dietary habits.
The researchers found that all 3 dietary patterns were inversely associated with a woman’s risk of developing T2DM. These findings held after they adjusted for the women’s age, ethnicity, age during first birth, parental diabetes history, use of oral contraceptives, total caloric intake, number of births, menopause, and smoking behavior.
Comparisons between participants in the highest and lowest adherence quartiles in each dietary pattern subgroup revealed a significantly lowered risk of T2DM among women with the highest levels of adherence: in the aMED group, the T2DM risk was 40% lower; in the DASH pattern, it was 47%; and, in the aHEI pattern, it was 57% lower. However, adjustments for body mass index among the participants did moderately reduce the effects.
The researchers conclude that adherence to healthy dietary behaviors is linked to a lower risk of T2DM in women who have had GDM.