Wednesday, September 14, 2016
Impact of Low-Glycaemic-Index Diet during Pregnancy on Maternal and Newborn Outcomes
Maternal nutritional status during pregnancy plays an important role in the growth and development of the foetus. Since glucose is the major energy substrate, a maternal diet with high glycaemic index (GI) is related to foetal overgrowth and increased body adiposity during infancy. A meta-analysis published in the European Journal of Nutrition aimed to assess the impact of low-GI diet on maternal and newborn outcomes.
In this meta-analysis, Zhang et al. conducted a systematic literature search for relevant randomised trials until January 2016 in the PubMed, Clinical Trials, and Cochrane Library databases. Eleven trials which involved 1985 women were eligible for the analysis. Combined treatment effects were calculated using random- and fixed-effects models.
Low-GI diets compared to control diets resulted in significant reduction in fasting blood glucose (FBG) (weight mean differences [WMD]: −0.18 mmol/L) and postprandial glucose levels (WMD: −0.33 mmol/L), and a somewhat lower gestational weight gain (GWG) (WMD: −0.69 kg). Additionally, low-GI diets compared to controls led to a borderline significant reduction in birth weight (WMD: −0.10 kg) and a significant reduction in the proportion of large for gestational age infants (RR: 0.52). No other maternal or newborn outcomes were affected by low-GI diets. Heterogeneity in FBG, GWG, and birth weight analyses was observed. The effect of low-GI diets on GWG and FBG varied in the sensitivity and subgroup analyses.
The findings of the meta-analysis suggest that a low-GI diet during pregnancy may confer beneficial effects on maternal outcomes, without any adverse effects on newborn outcomes. However, the results should be interpreted with caution in view of the evidence of heterogeneity across studies, limited number of trials, and possible publication bias.
News Source: Zhang R, Han S, Chen GC, et al. Effects of low-glycemic-index diets in pregnancy on maternal and newborn outcomes in pregnant women: a meta-analysis of randomized controlled trials. European Journal of Nutrition. 2016;9:1-1.