Low-carbohydrate, ketogenic diet in diabetes

 Does a low carbohydrate, keotgenic diet result in improved diabetes control in overweight people with type 2 diabetes mellitus?

Researchers from Duke University Medical Center in Durham, North Carolina compared a low-carbohydrate, ketogenic diet to a low-glycemic, reduced-calorie diet.

First, the details.

• 84 obese people with type 2 diabetes were randomly assigned to a diet for 24 weeks.
• A low-carbohydrate, ketogenic diet (less than 20 grams of carbs daily)
• A low-glycemic, reduced-calorie diet (500 kcal/day less than needed for weight maintenance).
• Both groups participated in group meetings and received nutritional supplementation and exercise recommendations.
• The main outcome was blood sugar control, measured by hemoglobin A1c.
• The A1c test shows the average amount of sugar in the blood over the last 3 months.
• Ketogenic diets are high fat, adequate protein, and low in carbohydrates.

And, the results.

• Both treatments improvemed A1c, fasting blood sugar levels, fasting insulin, and weight loss.
• The low-carb ketogenic diet group had significantly greater improvements in A1c, body weight, and HDL (good) cholesterol vs the low glycemic diet.
• Diabetes medications were reduced or eliminated in 95% of low-carb group vs. 62% with the low glycemic diet.

The bottom line?
Both diets led to better diabetes control, less need for anti-diabetic drugs, and weight loss over 24 weeks. However, the low-carb, ketogenic diet was most effective.

The greater effect of the low-carb ketogenic diet appeared to be due to the lower carbohydrate intake,” concluded the authors, “because statistical significance remained after adjustment for weight loss.

Long-term compliance is a problem with any diet. This is particularly true with the ketogenic diet. In 1 study, only 50% of children receiving the ketogenic diet remained on the diet after 1 year.

Similarly, in this study, 45% of those on the low-carb, ketogenic diet dropped out compared to 37% in the low-glycemic, reduced-calorie diet group.

With so many lifestyle changes required of people with diabetes, are the added benefits of a low-carb ketogenic diet — which are considerable — worth the effort? And at what point in treatment should patients be introduced to it?

1/7/09 20:42 JR