Reducing Carbs in GDM Doesn’t Prevent the Need for Insulin

Randomized control trial looked at patients with gestational diabetes who followed a low carb diet and those who ate a normal diet, comparing the need for insulin….

It was found the low carb diets are not effective in stalling the need for insulin in gestational diabetic patients. Carbohydrates may not be a key issue for nutritional therapy for gestational diabetes.

The percentage of patients who were started on insulin was 54.7% both among those who ate a low-carbohydrate diet and among those who ate a diet with a normal level of carbohydrates (P=1.00), according to Didac Mauricio, MD, PhD, of the University of Lleida in Spain, and colleagues.

Pregnancy and neonatal outcomes were similar in the two groups as well, the researchers reported

Nutritional therapy has been the treatment of choice for gestational diabetes. The therapy has been focused on reducing the carbohydrate consumption to maintain glycemic control.

The current study was a randomized controlled trial that included 152 women with gestational diabetes who were pregnant with a single child. The mean age of the participants was roughly 33.

The women were randomized to a low-carbohydrate diet in which 40% of calories came from carbohydrates or a control diet in which 55% of calories came from carbohydrates. Protein made up 20% of the total calories in both diets, whereas fat made up 40% of the low-carbohydrate diet and 25% of the control diet.

The women in this study all had 3 meals and 3 snacks daily and were randomized to either a normal diet or low carbohydrate diet. All the patients tested their own blood sugar levels.

During the study they found that regardless of diet there was no significant difference in the percentage of patients who needed to start insulin therapy. They also found that there were no difference in maternal weight gain, hypertension, need for cesarean delivery, gestational age, stillbirth, birth size and newborn hypoglycemia.

Overall it was determined that a low carbohydrate diet in gestational diabetic patients will not reduce the need for possible insulin therapy.

Practice Pearls:

• Be aware that pregnancy outcomes were similar in both groups as well.
• Note that this was a small randomized study

Moreno-Castilla C, "Low-carbohydrate diet for the treatment of gestational diabetes: a randomized controlled trial" Diabetes Care 2013; DOI: 10.2337/dc12-2714/-/DC1.