High-carbohydrate, low-fat diets increase the risk of heart disease in diabetic patients

This study was published in Diabetes Care 1989 Feb;12(2):94-101

Study title and authors:

Persistence of hypertriglyceridemic effect of low-fat high-carbohydrate diets in NIDDM patients.

Coulston AM, Hollenbeck CB, Swislocki AL, Reaven GM.

Department of Medicine, Stanford University School of Medicine, California.

This study can be accessed at: http://www.ncbi.nlm.nih.gov/pubmed/2539286

Coulston notes that although low-fat high-carbohydrate diets are recommended for patients with diabetes in an effort to reduce the risk of coronary artery disease, the results of short-term studies have shown that these diets can actually lead to an increased risk of heart disease.

In this study Coulston observed the effects of such diets compared to higher-fat diets over a longer period of 6 weeks in diabetic patients.

 

The diets were either:

• 60% carbohydrate, 20% protein, 20% fat (high-carbohydrate diet).
• 40% carbohydrate, 20% protein, 40% fat (high-fat diet).

The study found:

• The (bad) blood glucose and insulin concentrations were significantly elevated throughout the day when patients consumed the high-carbohydrate diet.
• The (bad) triglyceride concentrations increased by 30% when patients consumed the high-carbohydrate diet.
• The (bad) Very low density lipoprotein (VLDL) cholesterol was significantly increased when patients consumed the high-carbohydrate diet.
• The (good) High density lipoprotein (HDL) cholesterol levels were significantly decreased when patients consumed the high-carbohydrate diet.

This study shows that a high-carbohydrate, low-fat diet increases the risk of heart disease in diabetic patients.