Macronutrient composition and food groups associated with gestational weight gain: the GUSTO study.

PURPOSE: To examine the associations of energy, macronutrient and food intakes with GWG on 960 pregnant women from the Growing Up in Singapore Towards healthy Outcomes (GUSTO) mother-offspring cohort.

METHODS: Dietary intake was assessed at 26-28 weeks' gestation with a 24-hour recall and 3-day food diary. GWG z-scores were calculated from first (4-13 weeks' gestation) and last (30-40 weeks gestation) measured weights; inadequate and excessive GWG were defined using the Institute of Medicine recommendations based on weights between 15 and 35 weeks' gestation. Associations were examined using substitution models for macronutrient composition, with linear or multinomial logistic regressions.

RESULTS: Mean ± SD daily energy intake was 1868 ± 598 kcal, and percentage energy intakes were 51.8 ± 8.9% from carbohydrate, 15.7 ± 3.9% from protein and 32.6 ± 7.7% from fat. Higher energy intake (per 500 kcal increment) was associated with 0.18 SD higher GWG. In isocaloric diets, higher-carbohydrate and lower-fat intakes (at 5% energy substitution) were associated with 0.07 SD higher GWG, and 14% higher likelihood of excessive GWG. Concordantly, the highest tertile of carbohydrate-rich foods intake was associated with 0.20 SD higher GWG, but the highest tertile of fruit and vegetable intake was independently associated with 60% lower likelihood of inadequate GWG. Additionally, the highest tertile of dairy intake was associated with 0.18 SD lower GWG; and the highest tertile of plant-based protein foods intake was associated with 60% and 34% lower likelihood of inadequate and excessive GWG.

CONCLUSIONS: Balancing the proportions of carbohydrates and fat, and a higher intake of plant-based protein foods may be beneficial for achieving optimal GWG.