High-fat, low-carbohydrate diet may improve beta-cell function in patients with type 2 diabetes

People with type 2 diabetes on a high-fat, low-carbohydrate diet may have a better chance of reversing their diabetes than those on a low-fat diet, according to a small study published in the Journal of the Endocrine Society.

Type 2 diabetes is a disease where the beta cells in the pancreas cannot secrete enough insulin to control blood sugar.

We showed that three months of a ketogenic diet was able to improve beta-cell function in patients with type 2 diabetes, and these improvements were associated with changes in the proinsulin-C-peptide ratio, a biomarker of pancreas stress. Other than bariatric surgery or large-volume intentional weight loss, interventions for improving beta-cell function in type 2 diabetes do not currently exist."

Marian Yurchishin, M.S., University of Alabama at Birmingham in Birmingham, Ala.

A ketogenic diet is a high-fat, low-carbohydrate eating plan that shifts hepatic metabolism to favor the burning of fat over the storage of fat. The biochemical changes involved ultimately yield numerous health benefits that may include improved beta-cell function and can occur without substantial weight loss.

The authors studied 51 people with type 2 diabetes (71% female) between 55 and 62 years old on either a ketogenic or low-fat diet, both prescribed to be weight-maintaining, and compared the changes in their proinsulin to C-peptide ratio. The proinsulin to C-peptide ratio reflects beta-cell stress and has been shown to decrease following diet-induced weight loss.

They found that although both groups lost on average a modest amount of weight, a ketogenic diet decreases the proportion of proinsulin secreted to a greater extent than a low-fat diet in patients with early type 2 diabetes, a change that was associated with an improvement in beta-cell function.

"We suggest that a ketogenic diet may reduce stress on the pancreas and improve the ability of beta-cells to secrete insulin in patients with type 2 diabetes," Yurchishin said.

Other authors are Amanda Finn, Lauren Fowler and Barbara Gower of the University of Alabama at Birmingham; and Sara Vere-Whiting of the University of Glasgow in Glasgow, U.K.

The study was funded by the National Institute of Diabetes and Digestive and Kidney Diseases, the Nutrition Obesity Research Center of the University of Alabama at Birmingham, the Diabetes Research Center of the University of Alabama at Birmingham, and the National Heart, Lung, and Blood Institute.

"Greater Reduction in the Proinsulin-C-Peptide Ratio with a Ketogenic vs. Control Diet in Patients with Type 2 Diabetes" was published online.