A multinational team of researchers has put forward a comprehensive case for recommending dietary carbohydrate restriction as the default intervention in managing diabetes mellitus.
The critical review, which has been published online by the Nutrition Journal, presents 12 points to support the use of a low carbohydrate diet in people with type 2 and type 1 diabetes. In people with type 2 diabetes, the review recommends a low carbohydrate diet as the first intervention. In type 1 diabetes, a low carb diet is advised as the default diet in addition to taking insulin.
The 12 points listed by the researchers are backed up by results of clinical studies:
High blood sugar is the most important feature of diabetes control.
Increase in calorie intake and obesity has been driven by increases in carbohydrate intake.
Carbohydrate restriction provides benefits regardless of weight loss.
Carb restriction is the most reliable dietary intervention for weight loss.
Adherence to low carb diets in type 2 diabetes is as strong as other dietary interventions, and is often significantly stronger.
Generally, replacing carbs with protein is beneficial.
Increased total fat and saturated fat intake are not associated with increased heart disease risk.
Triglycerides are controlled by carbohydrate intake more than by lipids (LDL, HDL).
HbA1c is the greatest predictor of microvascular and macrovascular complications in patients with type 2 diabetes.
Lowering carb intake is the most effective method for decreasing triglyceride levels and raising levels of ‘good’ HDL cholesterol.
Patients with diabetes reduce their dependence o, or doses of, medication when following a low carb diet.
Intensive blood glucose reduction though carb restriction has negligible side effects compared with use of medication for the same effect.
Within the review, the researchers draw attention to the fact that the studies, aimed to show safety and effectiveness of a low fat diet in improving heart health, have universally failed to show benefit. The review also criticises the use of total and LDL cholesterol as markers of heart health, arguing that other markers have been consistently been shown to be stronger. Other markers include the ratio of total cholesterol over HDL and the ratio of triglycerides over HDL, both of which are easy to measure clinically.
The researchers call upon governments and health agencies to hold hearings on the issues presented in the review, adding that vigorous scrutiny should be part of the process.