Poster Topical Area: Energy and Macronutrient Metabolism
Location: Hall D
Poster Board Number: 400
Objective: Carbohydrate (CHO) intake has been associated with gestational weight gain (GWG), but the direction of this association is inconsistent. In the general population, some evidence suggests that individuals with obesity gain more weight on a high CHO diet. The purpose of this study was to test the hypothesis that women who are obese at entry to prenatal care have greater GWG when eating a high, versus low, CHO diet. We also hypothesized that GWG would not differ by CHO for women of normal weight.
Methods: Healthy women with a BMI in the normal weight (n=31) versus obese (n=28) range enrolled in this study in early pregnancy (13.2 ± 2.1 weeks). Women completed a three-day food diary at 16-20 weeks gestation and data were entered into the Nutrition Data System for Research (Nutrition Coordinating Center; University of Minnesota). A median split for percent kilocalories from CHO (median=49%; range: 32-75%) further categorized women into highCHO versus lowCHO groups (n=14-16/group). Total GWG was calculated as the difference in body weight measured at enrollment and at the last prenatal care visit (time between visits: 180±22 days; did not differ by group). Univariate analysis of covariance was used to examine whether the association of weight status with GWG differed for women in the highCHO versus lowCHO groups, after adjusting for total daily energy intake.
Results: A significant interaction between weight status and CHO content of the diet was found (P<0.05), such that there was no difference in GWG for women who were normal weight and consumed a highCHO versus lowCHO diet (12.5 ± 4.5 kg vs 15.5 ± 9.1 kg), but for women who were obese, those in the lowCHO group had less GWG than those in the highCHO group (7.9 ± 4.7 kg vs 13.6 ± 7.1 kg). The interaction did not change after adjusting for total energy intake.
Conclusions: Results suggest that intake of a relatively low CHO diet may help limit GWG among women with obesity. It is possible that this difference in GWG by CHO content of the diet was evident only for women with obesity because of differences in glucose metabolism and insulin action compared to women of normal weight. Additional studies should establish the feasibility using a low CHO diet as an intervention to limit GWG in women who are obese at conception.
University of Alabama at Birmingham