High-fat diet lowers blood glucose, improves HDL in diabetics

Eating food with a lot of fat and few carbohydrates can lower blood glucose levels and improve blood lipids in people with diabetes, according to a study from Linköping University.

The two-year dietary study included 61 patients with type 2 diabetes. They were randomly assigned to follow either a low-carbohydrate, high-fat diet or a low-fat diet.

The low-carbohydrate group showed significant improvement in glycemic control after six months. The average blood sugar level for that group decreased from 58.5 to 53.7 mmol/mol (the unit for average blood glucose). As a result, that group needed 30 percent less insulin to treat their diabetes.

Researchers also discovered that good cholesterol or HDL increased in the group consuming the high-fat diet. This result contradicts the assumption that a diet with a larger portion of saturated fatty acids would increase lipoproteins.

Participants in both groups lost an average of about 8.8 pounds over the two-year period. However, individuals in the low-fat group did not show any significant improvements in glycemic control or lipoproteins as a result of their weight loss.

However, conventional wisdom advises managing diabetes with diet and weight control. Mayo Clinic states that losing 5 to 10 percent of body weight for an overweight person can significantly improve blood sugar control.

Mayo Clinic also recommends a diet with limited amounts of saturated fats and heavy in fruits, vegetables, whole grains and legumes.

“You could ask yourself if it really is good to recommend a low-fat diet to patients with diabetes, if despite their weight loss they get neither better lipoproteins nor blood glucose levels,” said Fredrik Nyström, professor of Internal Medicine at Linköping University and co-lead on the study.

The low-carbohydrate diet consisted of 50 percent fat, 30 percent protein, and 20 percent carbohydrates. The low-fat diet consumed 55-60 percent carbohydrates, 30 percent fat, and 10-15 percent protein.

The study is being published in the journal Diabetologia.

Source: Linköping University, Mayo Clinic

Photo by John Nyboer