Issue 177 Item 4 Carbohydrate-Rich Diet Associated With Lower (HDL) High-Density

An elevated glycemic load is an independent risk factor for future coronary events in patients with coronary heart disease (CHD), results of the Long-term Intervention with Pravastatin in Ischaemic Disease(LIPID) study. Reported at the 13th International Symposium on Atherosclerosis. Kirsty Mehalski, MD, the National Health and Medical Research Council (NHMRC) Clinical Trials Centre, University of Sydney, Sydney, Australia, investigated the effect of dietary carbohydrates expressed as glycemic index (GI), and glycemic load (GL) on lipids and lipoproteins in patients with CHD.

The researchers defined glycemic index as the measure of blood glucose after consumption of carbohydrate-containing foods, ranging in values from 1 to 100. Glycemic load was defined as the carbohydrate content of a food multiplied by the glycemic index and servings per week.

As a subset of the Long-Term Intervention with Pravastatin in Ischaemic Disease (LIPID) study, 1,077 patients were assessed for dietary intake over a 5-year period. Participants were allowed a maximum of 30% of calories from fat, with 10% being saturated fat. They maintained a dietary cholesterol intake of less than 300 mg/day.

During the run-in period, patients completed a food frequency questionnaire of more than 170 foods. All carbohydrate foods consumed were allocated a glycemic index, and the glycemic load was calculated.

Results showed an inverse relationship between high-density lipoprotein (HDL) cholesterol level and both the glycemic index and glycemic load.
She explained that glycemic index and glycemic load are significantly related to HDL cholesterol such that eating a diet with large amounts of high glycemic index cholesterol is associated with a lower HDL concentration.

It was suggested that physicians should instruct patients with CHD to choose carbohydrate rich foods with low glycemic values including pasta, wholegrain breads and cereals, legumes, fruits, and vegetables.

Dr. Mehalski said that reducing saturated fat, lowering cholesterol levels, and increasing fiber content can result in the reduction of coronary events in patients with CHD.

[Study title: Glycaemic Load and Glycaemic Index are Determinants of HDL Cholesterol Levels in Patients With Coronary Heart Disease: Results From the LIPID Study. Abstract 4P-0950]