Metastudy affirms low-carb diets can reverse type 2 diabetes

A new systematic review and meta-analysis published in the British Medical Journal has concluded adhering to a low-carbohydrate diet for six months is the most effective dietary strategy to put type type 2 diabetes into remission.

A number of studies over the past few years have found dietary changes can be the most effective first-line treatment for those diagnosed with type 2 diabetes. Low-calorie diets, fasting diets and plant-based diets have all been shown to be potentially helpful in controlling, or even reversing, type 2 diabetes, and the new research set out to better understand what specific type of dietary intervention is best for type 2 diabetics.

A low-carbohydrate diet was defined in the new study as, “diets with less than 130 g/day or less than 26 percent of calories from carbohydrates based on 2,000 kcal/day.” This was compared to a control group composed of subjects consuming a similarly calorie-controlled diet prioritizing low-fat foods.

"We used the most robust scientific methods to examine the combined effects of 23 published clinical trials from across the world, involving 1,357 participants, including additional data from five of those clinical trials on markers of blood sugar status," explains Joshua Goldenberg, co-lead on the study. "By examining the totality of evidence on the effects of low carb diets against clinical targets, this study will help clinicians and patients to better understand how this dietary approach can be used to treat type 2 diabetes, which remains a significant and worsening problem worldwide, despite numerous pharmaceutical developments.”

The research found after six months following a low-carb diet subjects achieved higher rates of diabetes remission than those following other diets. Pooling together eight trials in particular the meta-analysis suggested a low-carb diet led to a 32 percent greater rate of disease remission compared to the controls.

The research also looked at longer-term effects of low-carb diets, investigating a number of studies with follow-up periods of 12 months. Importantly, the results revealed many clinically significant benefits from low-carb diets were seen to diminish around the 12-month mark.

Questions over the long-term safety of low-carbohydrate diets are not new. It has been suggested low-carb diets eliminate important food groups leading to adverse health effects in the long-term. One recent study in particular suggested too few carbohydrates in a person’s diet could be as detrimental over a long period of time as too many carbohydrates.

The team behind this new study point out the long-term data on this question is not clear and there are few clinical trials with robust data on the effect of carbohydrate restriction over a period of years. As far as this new review can ascertain, after 12 months on a low-carb diet some benefits do diminish and, “some evidence shows clinical worsening of quality of life and low density lipoprotein cholesterol.”

The ultimate conclusion offered by the current study is that, at least in the short-term, a low-carb diet looks to be the most effective dietary strategy to manage type 2 diabetes. Grant Brinkworth, a researcher from Australia’s CSIRO working on the study, says more work is still needed to offer clarity over the long-term effects of this dietary strategy as a therapeutic approach for diabetes.

"These results show low carb diets can be a really effective dietary approach for type 2 diabetes management, however, the challenge is to provide patients with easy-to-use support tools and convenient product solutions to help them adhere to it long-term to gain these greater health improvements," Brinkworth says. "In the future, having clearer a definition of type 2 diabetes remission and more rigorous studies examining the long-term safety and satisfaction of low carb diets will also help to confirm the strength of this therapeutic approach."

The new study was published in the BMJ.

Source: CSIRO