"When asked about the sources of cholesterol, most, more than three-quarters of respondents incorrectly identified the diet as the main source of the cholesterol in the body," Dr. David Cohen of Brigham and Women's Hospital in Boston told United Press International in a telephone interview. "In fact, three times the amount of cholesterol is naturally produced by the body than is obtained in the diet each day."
The survey by Harris Interactive included 1,118 people who reported they had high cholesterol -- 566 of them were being treated with medication to reduce cholesterol levels.
Cholesterol is a form of fat or lipid and is found in all body cells, including blood cells. It is critical to the maintenance of general health but excess low density lipoprotein -- the LDL or bad cholesterol -- can, over time, adhere to the inner walls of arteries supplying blood to the heart. It forms plaque deposits that narrow arteries, restrict blood flow and increase the risk of heart attack.
American Heart Association guidelines in place at the time of the survey prescribed an optimal level for LDL cholesterol of less than 100 milligrams per deciliter of blood.
Cohen said 85 percent of survey respondents claimed they were aware there were national guidelines for cholesterol levels in the blood but only 26 percent actually knew what they were.
Shortly before the results of the Harris survey were released, the American Heart Association came out with updated guidelines that said patients who have more than a 20 percent risk of heart attack in the next decade should reduce LDL cholesterol to below 70.
Risk level is calculated by a physician, using factors such as prior heart attack or stroke, heart disease or diabetes, family cardiovascular history, high blood pressure and smoking.
"In terms of public health, cardiovascular disease is the leading cause of death of Americans, and high cholesterol is a well established risk factor for heart attacks and strokes," Cohen said. "Numerous large, well designed clinical trials have proven that lowering LDL or 'the bad' cholesterol reduces the risk of these events."
Cohen said reducing the "cholesterol awareness gap" identified in the Harris survey "represents one way to improve cardiovascular health through education.
"If patients are made aware of the two sources of cholesterol, as well as their optimal goals for LDL cholesterol, they can better participate in strategies designed to reduce the morbidity and mortality related to cardiovascular disease," he added.
Bonna Kol, executive director of Mended Hearts, a survey co-sponsor, told UPI: "The survey revealed a surprising degree of confusion about the sources of cholesterol. But another finding that concerns us is that 92 percent of respondents not currently taking prescription medication indicated they think their cholesterol needs to be lowered.
"These were patients who reported having high cholesterol levels. These findings underscore the need, more than ever, for patients to be informed and discuss with their physicians a cholesterol-lowering plan that is best for them," Kol said.
Cohen said diet and exercise are critical to cardiovascular health but added: "In the setting of a healthy lifestyle, the only way to determine whether genetic factors are contributing to elevated cholesterol levels is to have a blood test. If cholesterol levels are still elevated, then a physician and patient can construct a strategy for minimizing this risk factor, which may involve the use of a cholesterol lowering medication."
Merck/ Schering-Plough Pharmaceuticals, in partnership with Mended Hearts Inc. of Dallas, sponsored the survey.