In response, researchers sought to compare the effects of low versus high carbohydrate consumption on glucose, insulin, and blood lipid levels. "Blood lipids" typically refers to triglycerides and the various forms of cholesterol, including low-density lipoprotein (LDL). These blood lipids are considered harmful when elevated.
For six weeks, 42 diabetic patients consumed a high-carbohydrate diet containing 55% carbohydrates and 30% fats followed by a high-monounsaturated fat diet containing 40% carbohydrates and 45% fats for an additional six weeks. Blood samples were frequently obtained for the assessment of cholesterol, triglyceride, and insulin levels.
Upon completion of the study, results demonstrated that "Compared with the high-monounsaturated-fat diet, the high-carbohydrate diet increased fasting plasma triglyceride levels by 24%...and LDL cholesterol levels by 23%."
Dr. Garg and colleagues stated that "[This] study, therefore, further substantiates the fact that high-carbohydrate diets offer no advantage in lowering LDL cholesterol levels in NIDDM patients compared with high-fat diets that are low in saturated fats." In conclusion, "Diets with higher proportions of...monounsaturated fats may be advantageous in reducing the long-term complications, particularly coronary heart disease, in [type 2 diabetic] patients."