Quick, what's your LDL, HDL and total cholesterol? If you draw a blank, you're not alone: A survey by the Society for Women's Health Research revealed that women were more likely to remember what they weighed in high school than the results of their latest cholesterol test.

"One of my patients had never even had her cholesterol checked until she came to see me," says Tracy L. Stevens, MD, medical director of the Muriel I. Kauffman Women's Heart Center at Saint Luke's Mid America Heart Institute in Kansas City, Missouri. "She was 28, an athlete, and she ate healthy, so she didn't think she had to worry about it." But her total cholesterol was 300. "Her mother also had high cholesterol, but the daughter didn't realize that she might have a genetic risk."

So why does cholesterol matter for every woman? When it's too high, cholesterol (a substance that causes plaque to build up on the artery walls, leading to blockages) is a major risk factor for heart disease, the number-one killer of women in this country. And there are no symptoms, so you won't know what your numbers are until you roll up your sleeve. "Knowing and managing your cholesterol levels long before your risk of heart disease goes up at menopause can help prevent heart attacks and strokes decades later," says Robert O. Bonow, MD, chief of cardiology at Northwestern Memorial Hospital in Chicago.

But being aware of your numbers isn't enough: It's crucial to understand the best ways to keep them at healthy levels. "There's so much to know—and doctors may not take the time to explain unless you ask," says Dr. Bonow. That's why we asked Drs. Stevens and Bonow and other cardiologists on the Woman's Day Heart Health Advisory Board to clear up the most common myths and misconceptions.

MYTH: Your total cholesterol is most important.
FACT: "It's the whole profile that matters," says Nieca Goldberg, MD, clinical associate professor of medicine at the New York University School of Medicine. That includes total cholesterol, HDL ("good" cholesterol), LDL ("bad" cholesterol), and the ratio of HDL to total cholesterol. It also includes triglycerides, another fatty substance in your bloodstream. In fact, high triglycerides are a stronger risk factor for heart disease in women than in men, and low HDL carries an even higher risk for cardiovascular disease than high LDL does.

MYTH: If your HDL is high, you've got nothing to worry about.
FACT: "No matter how good your HDL is, you can't just ignore LDL and other potential risk factors," says Dr. Stevens. High HDL is protective, but it can't cancel out other heart attack and cardiovascular disease risk factors including smoking, high blood pressure, diabetes and just plain getting older.

MYTH: To lower your cholesterol, you just need to change the way you eat.
FACT: Diet is important, but other lifestyle factors, such as exercising, losing weight and not smoking, are just as crucial. "I had a patient who quit smoking, cut down on carbs and started a moderate to vigorous walking program four days a week," says Dr. Goldberg." After four and a half months, she lowered her triglycerides from 250 to 130 and raised her HDL cholesterol from 39 to 52. Most people don't know that smoking lowers your HDL cholesterol in addition to the other terrible things it can do." That said, don't overestimate the power of diet and exercise to lower LDL. "If you have other risk factors, you may have to bring your LDL down to a level that's difficult to do with just lifestyle changes," says Dr. Goldberg. For example, if you already have heart disease and diabetes, it should be less than 70, which is extremely difficult to do without drugs.

MYTH: If you eat a healthy diet, aren't overweight and exercise regularly, you're not at risk for high cholesterol.
FACT: Genetics and age play a role, too. "Some people could eat nothing but celery and sawdust and their cholesterol would still be high because of a genetic predisposition," adds C. Noel Bairey Merz, MD, director of the Women's Heart Center at Cedars-Sinai Medical Center in Los Angeles. And your risk of developing high cholesterol goes up with age—no matter what, says Dr. Amparo Villablanca, MD, director of the Women's Cardiovascular Medicine Program at the University of California, Davis. "Just because it was normal when you were young doesn't mean it will stay that way.

MYTH: The worst foods for cholesterol are those that are high in cholesterol.
FACT: Eggs, shrimp and other high-cholesterol foods aren't great, but fried foods, red meat and full-fat dairy products are just as bad or worse. "Saturated fat will raise your bad cholesterol more than dietary cholesterol," says Lori Mosca, MD, director of preventive cardiology at New York-Presbyterian Hospital in New York City. It's also important to cut down on trans fats (found in some packaged baked goods) and simple carbohydrates like cakes, cookies and soda—which will help raise HDL and lower LDL and triglycerides.

MYTH: If you're taking medication, you don't have to make lifestyle changes.
FACT: If you're on a cholesterol- lowering drug but don't exercise and keep eating foods high in saturated fat and/or continue to smoke, you're still at an increased risk for a heart attack, not to mention stroke and diabetes. "The combination of lifestyle changes and medication can improve your cholesterol more than either drugs or lifestyle changes alone," says Dr. Goldberg. "Plus it can mean you can take a lower dose of the drug, which is always ideal." Eating well and exercising regularly can also reduce your heart disease risk by helping you maintain a healthy weight (or lose weight if you need to).

MYTH: It's OK to take an over-the-counter supplement to help lower cholesterol.
FACT: Just the opposite: OTC aids, such as red yeast rice, haven't been proven to lower heart disease risk, aren't regulated, and may not be safe, says Dr. Mosca. Even niacin, a type of B vitamin that can raise HDL levels and lower triglycerides, is best given in a prescription form rather than over the counter, says Dr. Goldberg. That way, you can be sure that the dosage is consistent from one bottle of pills to the next.

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