Very Low-Calorie Diet Can Reverse Type 2 Diabetes

A new trial has found that 8 weeks on a very low calorie diet can reverse all signs of type 2 diabetes mellitus (T2DM) in many patients for at least 6 months.

Investigators recruited 30 patients and measured their glucose control, insulin sensitivity, insulin secretion, hepatic fat content and pancreas fat content. The patients then discontinued all medications and began a 700-calorie-per-day diet that consisted of 3 diet milkshakes and 200 g of non-starchy vegetables. After a gradual return to an isocaloric diet, the investigators took new measurements and provided each individual with a structured program for weight maintenance.

Mean patient weight fell from 98.0 kg ± a standard deviation of 2.6 kg at baseline to 83.8 kg ± 2.4 kg after 8 weeks, and it remained stable until the end of the 6-month study, when average patient weight was 84.7 kg ± 2.5 kg.

More importantly, blood tests performed immediately after the return to a normal diet found fasting blood glucose levels < 7 mmol/L in 12 of the 30 patients, while blood tests performed at the end of the 6-month study found fasting blood glucose levels < 7 mmol/L in 13 of the 30 patients.

Responders, who were characterized by a return to first-phase insulin response, had a shorter duration of diabetes and a higher initial fasting plasma insulin level than non-responders.

HbA1c fell from 7.1% ± 0.3% to 5.8% ± 0.2% (55 mmol/mol ± 4 mmol/mol to 40 mmol/mol ± 2 mmol/mol) in responders (P < 0.001) and from 8.4% ± 0.3% to 8.0% ± 0.5% (68 mmol/mol ± 3 mmol/mol to 64 mmol/mol ± 5 mmol/mol) in non-responders. Those levels remained constant at the end of 6 months: 5.9% ± 0.2% (41 mmol/mol ± 2 mmol/mol) in responders and 7.8% ± 0.3% (62 mmol/mol ± 3 mmol/mol) in non-responders.

“A robust and sustainable weight loss program achieved continuing remission of diabetes for at least 6 months in the 40% who responded to a VLCD by achieving fasting plasma glucose of <7 mmol/L,” the study authors wrote in Diabetes Care. “T2DM is a potentially reversible condition.”

The authors of the new study are not the first to make such a conclusion, but the 6-month remission rates are higher than those found studies of less drastic diets. A 2012 study published in JAMA, for example, reported the results of a 4-year intensive lifestyle intervention (ILI) that included both diet and exercise. Just 11.5% (95% confidence interval [CI], 10.1%-12.8%) of more than 2,000 ILI group members experienced partial or complete remission after 1 year and just 7.3% (95% CI, 6.2%-8.4%) of group members experienced it after 4 years.

“In these exploratory analyses of overweight adults, an intensive lifestyle intervention was associated with a greater likelihood of partial remission of type 2 diabetes compared with diabetes support and education,” the authors of that study wrote. “However, the absolute remission rates were modest.”

Bariatric surgery, on the other hand, has consistently demonstrated the ability to produce significant remission rates, even in the long term. An analysis of a Swedish registry of obese patients found that, among 343 surgery patients who had T2DM at baseline, 72.3% were in remission after 2 years and 30.4% were in remission after 15 years.