7 Myths About Cholesterol, Debunked

10 minute read

You may not recall every lab value from your last physical, but you probably remember one: Your cholesterol level.

If it’s higher than ideal, you’re not alone. According to the U.S. Centers for Disease Control and Prevention, between 2015 and 2018, almost 12% of U.S. adults ages 20 and up had high total cholesterol, defined as above 240 mg/dL. The type that physicians mostly worry about is LDL (or “bad”) cholesterol, which is one component of that total.

Why do doctors care so much about cholesterol? First, “it predicts risk,” says Dr. Jeffrey Berger, a cardiologist and director of the Center for the Prevention of Cardiovascular Disease at NYU Langone in New York City. “It’s been shown in probably hundreds of studies that higher levels of LDL cholesterol is associated with a higher risk of having a heart attack, stroke, or early death.” And, crucially, it’s possible to modify this risk factor. “Numerous studies have shown that when you lower cholesterol, you decrease the risk of a cardiovascular event,” Berger says.

Doctors’ understanding of cholesterol, including how to best manage it, has evolved over the years. Read on for the latest information from experts.

The myth: Cholesterol is always harmful.

The facts: Cholesterol, which is often described as a fat-like, waxy substance, is essential to the human body, including playing a key role during fetal development. It’s part of cell membranes and prompts production of crucial hormones. But too much can cause problems, namely contributing to clogged arteries and raising the risk of heart problems. When physicians and researchers talk about cholesterol’s harms, they’re usually referring specifically to low-density lipoprotein. LDL transports cholesterol around the body, depositing it in blood vessels, explains Nathalie Pamir, an associate professor in preventive cardiology at the Oregon Health & Science University in Portland. Its smaller cousin, high-density lipoprotein (HDL), has long been thought of as the “good” cholesterol because it typically ferries cholesterol away from other parts of the body to the liver.

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Because LDL and HDL are different, doctors no longer focus so closely on the total amount of cholesterol. Instead, they generally ask people to aim for lower levels of LDL (optimally, below 100 mg/dL) and higher levels of HDL (at least 60 mg/dL, and not below 40 md/dL).

The myth: ‘Good’ cholesterol is always protective.

The facts: The story has gotten more complicated. LDL is still considered to be a bad actor: “Based on current research, there is no level where having it really low is dangerous,” says Dr. Leslie Cho, section head of preventive cardiology and rehabilitation at the Cleveland Clinic. In fact, people with heart disease should aim for less than 70 mg/dL, and people with diabetes and those at very high risk of coronary artery disease are advised to aim for less than 55 mg/dL, she says.

But the HDL story is more complex. Trials of experimental drugs for increasing HDL have not actually reduced heart events, and research has cast doubt on the idea that the higher the HDL levels, the better. Pamir and colleagues published a study in November in the Journal of the American College of Cardiology that followed nearly 24,000 adults without heart disease over about a decade to measure biomarkers and track heart attacks and heart attack-related deaths. While LDL, as well as another form of lipid, triglycerides, “modestly predicted” risk in white and Black adults, low HDL levels were associated with increased risk only in white adults. And high levels of HDL weren’t protective for either white or Black adults.

One potential explanation, Pamir says, is that the quality of the HDL’s functioning may matter more than the sheer quantity. There’s some evidence that high levels may indicate harmful inflammation, Wright adds. And excessive alcohol use or metabolic disorders may lead to higher HDL levels but not to better health. For now, there’s no test for the quality of HDL. Research into the intricacies of HDL by Pamir and others continues. Until there are more definitive answers, it’s important for people with high levels of HDL not to assume it will protect them from heart problems, to take the lifestyle steps that are known to improve heart health, and to talk with their physicians about medication if other factors suggest a higher heart disease risk, cardiologists say.

Read More: What to Know About High Cholesterol in Kids

The myth: You don’t need to get your cholesterol checked until you reach the average age for heart attacks.

The facts: Recommendations vary on when to start, but the AHA recommends that all low-risk adults ages 20 and older have their levels checked every four to six years. Screening will likely be more frequent if you have a family history or a personal history of heart disease. And the American Academy of Pediatrics recommends all children be screened for high cholesterol between the ages of 9 and 11—earlier if they have risk factors like a family history of early heart disease.

Cholesterol is measured using a blood draw. According to guidelines published in 2016, it’s usually not necessary to fast before your test. (Ask your doctor ahead of time to make sure.)

The myth: You have no control over your cholesterol levels.

The facts: To be sure, some influences on cholesterol are beyond your control. Infants are born with very low LDL cholesterol and levels “keep going up and up” as we age, Cho says. When women hit menopause and estrogen—which helps regulate lipid levels—wanes, their levels of LDL and triglycerides increase. “It’s an aging process. It’s not a moral failure,” Cho says. There are also racial differences. About 9.2% of Black male adults and 10.5% of Black female adults had high cholesterol between 2015-18, compared to 10.1% for white men and 13.1% for white women, according to a report from the American Heart Association.

But there are definitely some things you can do to keep your cholesterol in check, such as exercising. Regular high-intensity workouts, including running or biking at a good pace, can lower cholesterol by at least 10%, Wright says. Exercise also helps people sleep better and reduce stress, which can improve your heart and overall health. “No medication can replicate the physiological benefits of exercise,” Wright says.

And while weight loss can be difficult, you don’t have to lose much to see a positive effect. A 2016 review of weight-loss studies found that even losing 5-10% of your weight—so 10 to 20 pounds for a 200-pound person—resulted in “significant” reductions in total cholesterol, LDL cholesterol, and triglycerides. (Losing more weight was associated with larger improvements.)

The myth: If you have low cholesterol, you won’t have a heart attack.

The facts: This is “not at all” true, Cho says. Cholesterol is an important risk factor, but it’s not the only one, nor is it a perfect indication. Other heart risk factors include age (older people are more at risk), male gender, diabetes, tobacco use, and obesity, according to the American Heart Association (AHA). And an estimated 20% of total risk for what causes someone to have a heart attack isn’t known,” says Dr. R. Scott Wright, professor of cardiology at Mayo Clinic in Rochester, Minn. So don’t get too laser-focused on that number. “If you could choose between a life of high cholesterol yet a low risk of heart attack and stroke, or the opposite—low circulating LDL cholesterol yet a high risk of heart disease—you’d pick the first one,” Berger says. “You care about whether you’re going to have a heart attack or stroke.”

The myth: To keep your cholesterol low, you should avoid eggs.

The facts: If you’re a certain age, you may remember when “cholesterol-free” was plastered all over food packages. The U.S. Department of Agriculture used to recommend consuming less than 300 mg per dietary cholesterol per day. It stopped recommending a specific level in the 2015-20 nutrition guidelines, in part because Americans were, on average, not significantly exceeding that. In addition, the American Heart Association noted in a 2019 scientific advisory on dietary cholesterol that “evidence from observational studies conducted in several countries generally does not indicate a significant association with cardiovascular disease risk.”

Moreover, eating more cholesterol in your diet doesn’t necessarily translate to higher blood cholesterol for most people. The body also makes its own and can adjust to compensate if you eat more or less. That said, some people are highly sensitive to changes in their dietary cholesterol, and blood levels will fall dramatically if they lower their consumption, Cho says.

What does seem to increase LDL cholesterol are the types of fat that are “solid at room temperature,” Cho says. Those include saturated fats from animal products including meat, butter, and dairy. By contrast, unsaturated fats—which are liquid at room temperature—are beneficial. And eating too many simple carbs can lead to weight gain, Wright says. Rather than singling out specific foods, cardiologists now recommend a healthy eating pattern that incorporates plenty of fruits and vegetables, more healthful proteins such as fish, and monounsaturated fats. The Mediterranean diet fits the bill, cardiologists say, and has been associated with protection against other diseases, including diabetes and cancer.

Read More: How to Lower Your Cholesterol Naturally

The myth: You can always control your cholesterol level without help from medications.

The facts: Not all risk factors can be addressed. You can’t do anything about your age; nor can you change your genetic makeup. An inherited disorder called familial hypercholesterolemia causes about 1 in 200 people to be born with high LDL cholesterol levels, which will continue to rise throughout childhood and adulthood. It usually leads to heart disease, according to the AHA, though it can be treated with lifestyle measures and medications. While it’s a rare condition, other risk factors—such as weight and body type—also have genetic influences.

Even with weight loss and exercise, your physician may advise medications to keep your cholesterol in check. The most common are called statins, which decrease LDL levels. They are routinely prescribed to people who have already had a cardiac event to prevent another one, and also for preventing a heart event in the first place in those who are at increased risk. An updated evidence report from the U.S. Preventive Services Task Force, published in August 2022, found that using statins in at-risk populations was associated with a lower risk of cardiac events and death. The benefits occurred “across diverse demographics and clinical populations,” the review said.

Statins are “by far the most well-known [medication], and have the most amount of data,” Berger says. There are also newer drugs, he says, such as ezetimibe and PCSK9 inhibitors. The decision to prescribe medication is often based on risk calculators that gauge the 10-year risk of heart disease; most recent guidelines put the threshold at a 7.5% risk over the next decade, or 5% if the person has other high-risk features, he says. You should have a detailed conversation with your physician about the benefits and risks of medications.

Still, Berger emphasizes, exercise and diet are the first things to try, not just because they can improve your cholesterol, but because they improve overall health. A study published in the New England Journal of Medicine found that among people with a high genetic risk of heart disease, a healthy lifestyle (including diet and exercise) was associated with a 46% lower relative risk of coronary events than an unfavorable one.

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