MONDAY, Nov. 1 (HealthDay News) -- The success of a low-cholesterol diet can be improved by adding monounsaturated fat (MUFA), which are commonly found in nuts, seeds, avocados, and oils such as olive oil, canola oil and sunflower oil, new research suggests.

In the study, researchers randomly assigned 17 men and seven postmenopausal women with mild to moderate elevated cholesterol levels to either a high-MUFA diet or a low-MUFA diet.

Both groups consumed a vegetarian diet that 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.

In the high-MUFA group, levels of "good" cholesterol (high-density lipoprotein cholesterol, or HDL) increased 12.5 percent while levels of "bad" cholesterol (low-density lipoprotein cholesterol or LDL) decreased 35 percent, according to the report in the Nov. 1 issue of CMAJ, the Canadian Medical Association Journal.

People with low HDL levels and high LDL levels are at increased risk for cardiovascular disease, Dr. David Jenkins of the Clinical Nutrition and Risk Factor Modification Center at St. Michael's Hospital in Toronto, and colleagues explained in a news release from the journal's publisher.

"The addition of MUFA increased [HDL] and therefore may further enhance the cardioprotective effect of the cholesterol-lowering dietary portfolio without diminishing its cholesterol-lowering effect," Jenkins and colleagues wrote.

Monounsaturated fats are commonly consumed in what is known as the Mediterranean diet, noted the researchers, who added that exercise, moderate alcohol consumption, not smoking and weight loss can also help raise "good" HDL cholesterol.

More information

The American Heart Association has more about cholesterol.