A randomized control trial was performed by Didac Mauricio, MD, PhD, of the University of Lleida in Spain, and colleagues for 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 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, included 152 women with mean age of 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.

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.