Fatty Food Not so Bad for Diabetes?

Type 2 diabetes patients may improve blood sugar through low carbohydrate diet

(RxWiki News) We are usually told to steer clear of fatty foods, especially those us with type 2 diabetes. This is generally good advice. Yet one team of researchers found that high fat foods may not be all that bad for diabetes patients.

People with type 2 diabetes who ate food with lots of fat but few carbohydrates had better blood sugar control than those who ate a low-fat diet.

"Eat more good cholesterol while avoiding bad cholesterol."

Obesity is one of the main causes of diabetes around the world. For this reason, people with diabetes or pre-diabetes are told to avoid fatty foods in order to lose weight.

However, results from a study led by Hans Guldbrand, M.D., a general practitioner, show that controlling diabetes may have more to do carbohydrates than fats.

Dr. Guldbrand and colleagues wanted to see what kind of diet was better for diabetes patients. They split up 61 people with type 2 diabetes into two groups: one that ate a low-fat diet and one that ate a low-carbohydrate diet.

While both groups lost about the same amount of weight, the low-carbohydrate group had much better blood sugar control than the low-fat group after six months.

Even though the low-carbohydrate group ate much higher levels of fat, they did not have worsening levels of lipoproteins, or molecules made of proteins and fat. High levels of lipoproteins can raise the heart disease, a condition for which diabetes patients already have an increased risk.

In comparison to the low-carbohydrate group, the low-fat group did not gain better blood sugar control nor improved lipoprotein levels.

"We have known for some time that low-fat diets are not effective -- it is the quality of fats consumed that is key," explains Timothy S. Harlan, M.D., of the Tulane University Multispecialty Clinic in New Orleans.

"At the same time we also know that lower carbohydrate diets are beneficial for diabetics but this level of carbohydrate consumption is too low to be sustainable by most people. This is an interesting, small study but doesn't advance the science further than information that was already available to us," says Dr. Harlan, who was not involved in the study.

"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 [sugar] levels," says Fredrik Nyström, Ph.D., professor at Linköping University and one of the study's authors.

Through eating a high-fat, low-carbohydrate diet, diabetes patients had a drop in average blood sugar levels from 58.5 to 53.7 mmol/mol. Someone with a blood sugar level of more than 42 mmol/mol is considered to have diabetes.

Because patients in the low-carbohydrate group saw such improvements to their blood sugar, they were able to lessen the intensity of their treatment. That is, they did not need to take as much insulin. In fact, the amount of insulin used in treatment was lowered by 30 percent.

"In contrast to most other studies of this type, we lost no patients at all, which vouches for the good quality of our data," says Dr. Guldbrand.

This research received funding from the University Hospital of Linköping Research Funds, Linköping University, the County Council of Östergötland, and the Diabetes Research Center of Linköping University.

It is published in the journal Diabetologia.

Review Date: 
May 11, 2012