Monounsaturated fatty acids in diet improve cholesterol levels
Posted Nov 15 2010 12:00am
CMAJ.ca - Adding monounsaturated fats (MUFA) to a cholesterol-lowering dietary portfolio in patients with mild to moderate elevated cholesterol levels increased HDL by 12.5 percent and lowered LDL levels by 35 percent, according to a study published in CMAJ (Canadian Medical Association Journal).
Low HDL-C levels and high LDL-C levels are a risk factor for cardiovascular disease. The addition of dietary monounsaturated fatty acids, common in the Mediterranean diet, is a current approach to raising HDL-C levels.
The randomized, controlled trial (pilot study) included 24 patients (17 men and 7 postmenopausal women) who completed a very low saturated fat diet before being assigned to either a high-MUFA diet or a low- MUFA diet. Both groups of patients were assigned to a specific vegetarian diet which included oats, barley, psyllium, eggplant, okra, soy, almonds and a plant sterol enriched margarine. In the high-MUFA group, the researchers substituted 13 percent of calories from carbohydrates with a high-MUFA sunflower oil, with the option of a partial exchange with avocado oil.
They found significant reductions in blood cholesterol levels over the two month study period for participants.
“The replacement of 13 percent of total calories from carbohydrate by monounsaturated fats in the dietary portfolio resulted in a 12.5 percent greater increase in HDL-C over the four weeks, while not altering the substantial LDL-C reduction,” writes Dr. David Jenkins, Clinical Nutrition and Risk Factor Modification Centre, St. Michael’s Hospital, Toronto, with coauthors.
Other strategies to raise HDL-C include exercise and moderate consumption of alcohol as well as weight loss and smoking cessation.
“The addition of MUFA increased HDL-C and therefore may further enhance the cardioprotective effect of the cholesterol-lowering dietary portfolio without diminishing its cholesterol-lowering effect,” state the authors.
However, they state that the long-term effect on diets that are self-directed by patients needs to be determined as do cardiovascular outcomes.
The abstract of the study is available here:
Reference: David J.A. Jenkins, et al. “Adding monounsaturated fatty acids to a dietary portfolio of cholesterol-lowering foods in hypercholesterolemia” Published online ahead of print November 8, 2010. CMAJ 10.1503/cmaj.092128