In motivated people who are overweight and have type 2 diabetes, a low-carbohydrate diet with some caloric restriction has lasting benefits on body weight and blood sugar control, Swedish researchers report.

Dr. Jorgen Vesti Nielsen and Dr. Eva A. Joensson from Blekingesjukhuset, Karlshamn, previously reported that 16 obese patients with type 2 diabetes who followed a low carbohydrate diet achieved significantly better diabetes control and body weight over 6 months than did 15 patients who followed their usual diet.

Follow-up data at 22 months for the low-carbohydrate group now show “stable improvement” of body weight and glucose control, the investigators report in the journal Nutrition and Metabolism.

At the start of the study, the average body weight of the participants was 100.6 kg in the low-carbohydrate group. At 6 months, they were down to 89.2 kg, and by 22 months they were at 92.0 kg.

Moreover, hemoglobin A1c, an indicator of ongoing blood glucose control, dropped from 8.0 percent in the low-carbohydrate group to 7.0 percent after a year, and at 22 months it was still down, at 6.9 percent.

The low-carbohydrate and high-carbohydrate diet contained about the same amount of calories (1800 kcal for men and 1600 kcal for women), but the proportions of carbohydrates, protein, and fat were different: 20 percent, 30 percent, and 50 percent, respectively, for the low-carb diet versus 55-60 percent, 15 percent, and 25-30 percent, respectively, for the higher-carb control diet.

In comments to Reuters Health, Nielsen said: “There is no such thing as one diet that all patients should adapt to. Some prefer to eat as they are used to and treat the blood glucose with medications. Others are willing to make quite substantial changes in their lives in order to get healthier (and in some cases to get cured of their diabetes).”

When it comes to diet and diabetes, Nielsen acknowledges that “we know very little and patients should be informed about our lack of knowledge so they can make their own choices. And then they should get our full support in whatever they chose.”

SOURCE: Nutrition and Metabolism 2006.