Healthy eating in pregnancy

Most pregnant woman want to know the best foods to eat and what to avoid. The possible dangers of eating liver, the need to avoid unprocessed cheeses and too much tuna, and, above all, the importance of folate supplements are widely appreciated. Two linked papers from Australia (Dodd and colleagues; doi:10.1136/bmj.g1285) and Norway (Englund-Ogge and colleagues; doi:10.1136/bmj.g1446) have explored whether eating “healthily” can improve clinically important pregnancy outcomes.1 2

Dodd and colleagues looked at the global prevalence of overweight and obesity among women in antenatal care and the associated complications, including risks of gestational diabetes and delivery of overlarge infants. Women in their LIMIT trial were advised to maintain a balance of carbohydrates, fat, and protein in their diet; to reduce consumption of foods rich in refined carbohydrates and saturated fat; and to increase intake of fruit, fibre, and vegetables; a regimen that should reduce insulin resistance, central to the complications of obesity in pregnancy. They were also encouraged to take physical exercise. This randomised controlled trial of a lifestyle intervention in overweight and obese women was adequately powered to address clinical outcomes. Previously small and often poorly designed studies have been undertaken with a surrogate clinical endpoint, notably gestational weight gain. Meta-analysis of these has shown no evidence for …