The study, published in the December 2002 issue of Metabolism, is the first to examine the effects of these dietary components in combination. Scientists have known for many years that, individually, soy proteins, nuts, viscous fibres such as those found in oats and barley, and plant sterols (a substance found in vegetable oils and also in leafy green and non-starch vegetables) have the ability to reduce blood cholesterol levels by approximately four to seven per cent. However, the study found that mixing these components together in a "combination diet" reduced levels of LDL cholesterol - the so-called "bad" cholesterol believed to clog coronary arteries - by a dramatic 29 per cent. The finding suggests this combination diet may be as effective as the first generation of a class of drugs known as statins, which have been the standard drug therapy for high cholesterol for the last 15 years.
"This opens up the possibility that diet can be used much more widely to lower blood cholesterol and possibly spare some individuals from having to take drugs," said lead author David Jenkins, a professor in U of T's Department of Nutritional Sciences and director of the Clinical Nutrition and Risk Factor Modification Centre at St. Michael's Hospital.
Jenkins and his research colleagues measured the cholesterol levels of 13 people who went on the combination diet for a month. The diet followed a seven-day plan using foods available in supermarkets and health food stores, including vegetables such as broccoli, carrots, red peppers, tomato, onions, cauliflower, okra and eggplant; oats, barley and psyllium; vegetable-base
Contact: Jessica Whiteside
University of Toronto