Low-glycaemic index foods help improve outcomes in women at high risk of GDM

Women who are at high risk of gestational diabetes mellitus (GDM) appear to benefit from having a low-glycaemic index (GI) or low glycaemic load diet, with a recent study showing that such a diet can control maternal weight gain and reduce the incidence of adverse neonatal outcomes.

For the study, researchers conducted a systematic review and meta-analysis to examine the impact of low GI or low glycaemic load diets in pregnant women at high risk of GDM. Multiple online databases were searched for relevant randomized controlled trials of low GI dietary interventions.

The initial search yielded 2,131 articles, among which 1,749 titles and abstracts were analysed. A total of 71 documents met the eligibility criteria, of which 10 studies involving 2,304 participants were retained and included in the meta-analysis.

Compared with control, a low GI diet had favourable effects in terms of controlling the range of weight gain (weighted mean difference [WMD], –1.01, 95 percent confidence interval [CI], –1.41 to –0.61), reducing the incidence of excessive weight gain (odds ratio [OR], 0.69, 95 percent CI, 0.54–0.87).

Regarding neonatal outcomes, a low GI diet lowered the incidence of large-for-gestational-age (OR, 0.32, 95 percent CI, 0.16–0.62) and preterm birth (OR, 0.45, 95 percent CI, 0.29–0.71).

The present data provide evidence of the benefit of low GI or low glycaemic load diets for pregnant women at high risk of GDM. However, the effects of the diets on the prevention of GDM, insulin levels, and neonatal head circumference, among others, are less certain, according to the researchers. Given the limited number of studies, more evidence from high-quality studies is warranted.