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Misconceptions about cholesterol

From TV commercials to cereal boxes, the warnings about high cholesterol are hard to ignore. But they can also be hard to understand. We’re told LDL is “bad,” for example, and HDL is “good,” but did you know that neither of them is actually cholesterol?

Then there’s the distinction between dietary cholesterol – the kind you eat – and blood cholesterol, which exists in every cell of your body. The latter, produced in the liver and other organs, regulates metabolism and hormones. This precious substance gets transported around the bloodstream via LDL and HDL, which are actually low-density and high-density lipoproteins.

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“When LDL levels are high and HDL levels are low, cholesterol accumulates and plaque forms within the blood vessel walls, which can constrict blood flow, causing a heart attack,” says cardiologist Michael McConnell of Stanford University School of Medicine.

Dietary cholesterol, meanwhile, is found in eggs and other animal proteins. The amount you ingest has less of an impact on cardiovascular health than you might think. Here, we clear up the misconceptions so you can maximize your heart health.

THE MAIN CAUSE OF HIGH TOTAL CHOLESTEROL IS EATING A LOT OF CHOLESTEROL-RICH FOODS.

“This is one of the most persistent misconceptions,” says registered dietitian Janet de Jesus. The biggest culprit behind elevated LDL (the bad kind) is saturated fat, found in meats and high-fat dairy foods. Trans fats like hydrogenated oils also raise LDL levels.

YOU ONLY HAVE TO BE CONCERNED ABOUT HIGH CHOLESTEROL IF YOU’RE OVERWEIGHT.

“Being normal weight doesn’t mean you don’t need to worry about heart disease,” says registered dietitian Elisabetta Politi. “I have seen clients who are 400 pounds and have normal cholesterol and slender people with dangerously elevated numbers.”

SOME FOODS CONTAIN “GOOD” CHOLESTEROL.

“There’s no such thing as good cholesterol in food,” says Politi. But there are foods that can lower LDL. The most potent are those with soluble fiber – beans, whole grains, and some fruits and vegetables.

WITH A FAMILY HISTORY OF HIGH CHOLESTEROL, YOU NEED MEDication TO BRING IT DOWN.

“I hear this a lot from patients,” says McConnell. “Genetics definitely play a part, with 1 in 500 Americans having familial hypercholesterolemia — typically, total cholesterol over 290 or LDL over 190 — warranting thorough evaluation and family screening. Some people do need to take medications, such as statins, that lower cholesterol. But choosing healthy foods, losing excess weight and being more active can go a long way to bring cholesterol levels into line, even in people with a family history.”

FOODS LABELED “ZERO CHOLESTEROL” ARE ALWAYS GOOD FOR YOUR HEART.

Many foods with this label are loaded with saturated fats or too much salt, which can raise blood pressure and up the risk of heart disease. Some contain a lot of sugars, which increases the odds of diabetes, another threat to the heart.

IF CHOLESTEROL LEVELS ARE NORMAL, YOU DON’T HAVE TO WORRY ABOUT HEART DISEASE.

This is one of the most dangerous myths around. Cholesterol levels are just one of several risk factors for heart disease. Others include high triglycerides (fat particles in the bloodstream), insulin resistance, and high blood pressure. If you smoke or are sedentary, you run a big risk of heart disease even if your cholesterol levels seem ideal.

Adapted from Martha Stewart Living.
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