Pre-pregnancy Dietary Changes May Reduce Gestational Diabetes Risk

A woman’s diet before pregnancy can affect her risk of developing gestational diabetes, according to researchers from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD). Since fatty acids play an important role in glucose homeostasis, Dr. Katherine Bowers, research associate in the division of epidemiology statistics and prevention research at the NICHD, and colleagues explored whether the total amount, type, and source of pre-pregnancy dietary fats affect the risk of developing gestational diabetes mellitus.

Bowers et al. analyzed data from the Nurses’ Health Study II, a prospective study of 13,475 women aged 22 years to 45 years who reported a singleton pregnancy; 860 of these patients developed gestational diabetes. The women were asked to complete questionnaires on their general health, pregnancy status, and lifestyle habits (e.g., alcohol consumption and smoking) every two years and a comprehensive food and drink questionnaire every four years.

Bowers and colleagues found that a diet higher animal fat and cholesterol was significantly associated with increased risk of gestational diabetes. In fact, after adjusting for non-dietary risk factors, women who had consumed the most animal fat (i.e., those in the highest quintile of animal fat intake) had approximately a 90% increased risk for having gestational diabetes. Bowers et al. also find an increased risk of gestational diabetes among women who had higher intakes of cholesterol.

However, the researches failed to find a significant association between dietary polyunsaturated fat, monounsaturated fat, or trans fat and risk of gestational diabetes. Furthermore, Bowers and colleagues found that by substituting 5% of their total caloric intake from animal fat to plant-derived sources women could reduce their risk of gestational diabetes by 7%.

While medicine has recognized that obesity is a risk factor for developing gestational diabetes, it may not be obesity in and of itself causing the increased risk, Bowers noted in an interview. Instead, the independent and specific dietary factors (e.g., animal fats) may be playing an important role in the development of the disease.

The study has clinical implications for clinicians counseling patients who are considering pregnancy. “Our findings indicate that women who reduce the proportion of animal fat and cholesterol in their diets before pregnancy may lower their risk for gestational diabetes during pregnancy,” Dr. Cuilin Zhang, senior author of the study and investigator in the Epidemiology Branch at the NICHD, said in a press statement. She added that pre-pregnancy planning should include dietary counseling.

References:

References
Bowers K, Tobias DK, Yeung E, et al. A prospective study of prepregnancy dietary fat intake and risk of gestational diabetes. Am J Clin Nutr. 2012;95(2):446-53.
NIH News. High animal fat diet increases gestational diabetes risk. January 25, 2012