Higher-fat diets are a more effective treatment for diabetes than low-fat diets

This study was published in Diabetes Research and Clinical Practice 2004 Sep;65(3):235-41

Study title and authors:

Beneficial effect of low carbohydrate in low calorie diets on visceral fat reduction in type 2 diabetic patients with obesity.

Miyashita Y, Koide N, Ohtsuka M, Ozaki H, Itoh Y, Oyama T, Uetake T, Ariga K, Shirai K.

Center of Diabetes, Endocrine and Metabolism, Sakura Hospital, School of Medicine, Toho University, 564-1 Shimoshizu, Sakura-City, Chiba 285-0841, Japan.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/15331203

The aim of this 4 week study was to compare the effects of a low calorie high fat diet and a low calorie low-fat diet in obese subjects with type II diabetes.

22 diabetics received diets of either:
(i) 1000 calories per day, 65% carbohydrate, 25% protein, 10% fat (low-fat diet).
(ii) 1000 calories per day, 40% carbohydrate, 25% protein, 35% fat (higher-fat diet).

The study found:
(a) The harmful fasting high blood insulin levels were reduced by an extra 20% in the higher-fat diet group compared to the low-fat diet group.
(b) The beneficial high-density lipoprotein (HDL) cholesterol increased in the higher-fat diet group by 15% but did not increase in the low-fat diet group.
(c) There was a four-fold larger decrease in visceral fat area in the higher-fat diet group compared to the low-fat diet group. (Abdominal, or visceral, fat is of particular concern because it’s associated with a variety of health problems, such as high blood pressure, diabetes, heart disease and stroke — much more so than subcutaneous fat, which is found just under the skin. Visceral fat, on the other hand, lies out of reach, deep within the abdominal cavity, where it pads the spaces between the abdominal organs).
(d) The ratio of visceral fat area to subcutaneous fat area did not change in the low-fat diet group, but it decreased significantly in the higher-fat diet group.

The results of the study suggest that, a low-calorie/higher-fat diet might be more effective treatment for a reduction of visceral fat, improved insulin sensitivity and an increase in high-density lipoprotein (HDL) cholesterol levels than a low calorie/low-fat diet in obese subjects with type II diabetes.

Links to other studies:
Diabetes treated successfully by high fat, low carbohydrate diets
High fat/low carbohydrate diet decreases risk of heart disease
The case for high fat/low carbohydrate diets in diabetes management