Gestational diabetes affects pregnant women. Treatments typically include dietary changes and/or insulin treatment. In patients requiring insulin treatment, changing to a low-carb diet did not decrease the need for insulin therapy, according to a trial published in the journal Diabetes Care.

The trial involved about 150 pregnant women diagnosed with gestational diabetes during a singlet pregnancy. The average age during pregnancy was 33. Study participants were split into two groups – low-carbohydrate (40% of calories from carbs) and normal-carbohydrate diet (55% of calories from carbs). The low-carb dieters consumed 40% of calories from fat where as normal-carb dieters consumed 25% of calories from fat. All women were fed three meals and three snacks per day. Food journals were used to track carbohydrate intake and the pregnant women self-tested blood glucose levels for the sake of the study.

Women who tested above target blood glucose levels (5.3 mmol/L fasting or before meal or 7.8 mmol/L after meal) were started on insulin. Relatively the same number of women in the low-carb diet and normal-carb diet were started on insulin. Insulin dose and time in pregnancy when insulin was started were also comparable.

Despite the results of the study, experts are not sold on the accuracy of the findings. Consuming 40% of calories from carbohydrates is not considered a low-carb diet by most medical professionals. Patients with type 2 diabetes are typically advised to consume about 150 grams of carbohydrates per day. That accounts for 30% of a 2,000 calorie diet – not 40%. The Dietary Guidelines for Americans suggests consuming 50% of daily calories from carbohydrates for healthy individuals. According to this study, reducing carbohydrate intake by just 10% over suggested intake is considered following a low-carb diet.

Further research could be needed to address the impact of a low-carbohydrate diet and very low carbohydrate diet on gestational diabetes and insulin need. No such study plans are addressed by authors of the study published in Diabetes Care.

Source: Moreno-Castilla C, Hernandez M, Bergua M, Alvarez MC, Arce MA, Rodriguez K, Martinez-Alonso M, Iglesias M, Mateu M, Santos MD, Pacheco LR, Blasco Y, Martin E, Balsells N, Aranda N, Mauricio D. Low-Carbohydrate Diet for the Treatment of Gestational Diabetes: A randomized controlled trial. Diabetes Care. 2013 Apr 5. doi: 10.2337/dc12-2714.