Healthy foods

A study run for the National Institutes of Health (NIH) shows low carbohydrate diets to be better for weight loss and for heart health than low fat diets.

The study reviewed 148 men and women over a 12 month period. Participants selected were between 22 and 75 years old, with a BMI between 30 and 45 and no history of conditions such as heart disease, diabetes or thyroid disease.

The participants were randomly assigned to either a low carbohydrate or a low fat diet. The low carbohydrate diet involved a carbohydrate intake of less than or equal to 40g of carbohydrate per day. The low fat diet involved a intake of under 35% of calories from total fat and under 7% of calories coming from saturated fat.

At the end of 12 months, participants in the low carb group had lost 3.5kg more than those in the low fat group. The low carb group also experienced greater improvements in the following markers of heart health compared with the low fat dieters:

  • 0.18 mmol/l (7.0 mg/dl) higher level of HDL cholesterol
  • 0.16 mmol/l (14.1 mg.dl) lower level of triglyceride levels
  • 0.44 lower ratio of total cholesterol over HDL cholesterol

The study will be of interest to people with diabetes because, whilst studies of low carb diets have previously shown benefits in terms of blood glucose control for people with diabetes, there have been questions about whether low carb diets are safe in terms of heart health.

The fact that the results of the study show clear advantages in terms of weight loss and cardiovascular health benefits, opens the chance of further National Institutes of Health run trials into people with diabetes.

It should be noted that low carbohydrate diets presents extra complexity in people with diabetes, particularly those on medication that can cause hypos. People with diabetes should consult their doctor if considering a significant change of diet.