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.
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.
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.
Read More: https://time.com/6287926/cholesterol-myths-debunked/