High cholesterol can be inherited. Here’s what you can do about it

Most people associate high cholesterol with an unhealthy diet and a sedentary lifestyle—a condition that develops over many years and you only need to worry about as you get older.

However, this isn’t always the case. For some, high cholesterol isn’t the result of their habits, but rather their genetics—a disease called familial hypercholesterolemia (FH).

“In this condition, people have a genetic mutation that causes high LDL cholesterol levels in a lifelong manner,” says Ashish Sarraju, a preventive cardiologist at the Cleveland Clinic. The U.S. Centers for Disease Control and Prevention reports that 1 in 250 people have FH. Sarraju estimates that 70 percent or more of them may be undiagnosed—while some research suggests the number is upward of 90 percent.

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Recognizing the signs and symptoms of high cholesterol is crucial so you can take steps to manage it. National Geographic spoke with three cardiologists to explain what you need to know about inherited high cholesterol.

What is cholesterol—and what makes it so dangerous?

Cholesterol is a fatty, waxy compound that every cell in our body needs multiple doses of every day to function, according to Stephen Kopecky, a cardiologist at the Mayo Clinic and author of Live Younger Longer.

“Our cell walls are made of cholesterol, our hormones use cholesterol to be made,” Kopecky says. “A human adult has about 30 trillion cells in their body. And basically, every one of them needs tens of thousands of doses of cholesterol a day. So there’s a huge amount of cholesterol going around our body—and it’s essential.”

To transport cholesterol around your body to your cells, it’s packaged in particles called lipoproteins, according to Gregory Katz, a cardiologist at NYU Langone Health.

Most people have heard of “good cholesterol” (high-density lipoprotein, or HDL) and “bad cholesterol” (low-density lipoprotein, or LDL), which everyone has in their body. But cholesterol itself isn’t good or bad, Katz explains—the term refers to how the cholesterol is packaged and how it’s being transported around the body.

HDL cholesterol carries LDL cholesterol away from your arteries and into your liver, where it’s then broken down and excreted, according to the American Heart Association (AHA). But if there are too many LDL lipoproteins floating around, they can get stuck in the walls of your arteries and cause inflammation. And the artery wall isn’t made to be a storage receptacle for cholesterol—it’s a foreign substance, Kopecky says. 

“Think of a splinter in your hand—it turns red, it turns hot. It’s the same thing with the cholesterol in your artery wall,” Kopecky says. “Your artery wall gets warmer because the body sends white blood cells in there to get rid of it. And as it does that, it can tear the lining of the artery. And if it tears the lining, it can expose the blood beneath it. And the blood thinks, ‘Oh my god, our whole artery is torn through, let’s clot.’ And when it clots, that’s what causes a heart attack or stroke.”

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High cholesterol doesn’t typically cause symptoms before you get to that point, Katz says, which is what makes it so dangerous. Most people find out they have high cholesterol through routine bloodwork. “There are instances of people going to the orthopedic surgeon with Achilles injuries and, for the first time in their life, are found to have high cholesterol,” Kopecky says.

But there are a subset of people whose cholesterol is so high they can actually have signs of elevated cholesterol either depositing in their tendons, on their skin in plaque-like skin tags, or in their eyes in the form of a white ring where the iris meets the white of the eye, according to Kopecky.

How to find out if your high cholesterol is inherited

Lifestyle factors like lack of exercise, an unhealthy diet, and obesity are the most common causes of high cholesterol levels, according to the AHA. This typically means a total cholesterol amount above 200 milligrams per deciliter of blood, or mg/dL. Optimal cholesterol is around 150 mg/dL.

When high cholesterol is caused by lifestyle factors, you can reverse it with healthier choices. But that’s not an option for people with familial hypercholesterolemia, which can occur if one or both of your parents has a genetic mutation, according to Sarraju. But it’s still incredibly important to diagnose it early as there are things you do to prevent the worst outcomes.

Some pediatric guidelines recommend cholesterol testing for children between nine and 11 years old if the parents have FH, but kids could be screened earlier in some instances, Sarraju says. He recommends talking to a specialist for individual recommendations.

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As an adult, however, there’s “no age that is too early to be tested,” Sarraju says. If you have a family history of high cholesterol, heart attacks, or strokes, but no one was screened for a condition like FH, you should get your cholesterol checked as an adult right away.

It’s worth noting that a large portion of people who have FH also have elevated lipoprotein(a), according to the American College of Cardiology. Lipoprotein(a) is another particle that carries cholesterol and causes heart disease, and is also largely genetic, Sarraju explains. Research suggests that elevated levels of lipoprotein(a) increases risk of heart disease in those with FH.     

What to do if you have inherited high cholesterol

Once you find out you have FH, your doctor will likely advise paying attention to your diet and exercise habits, according to Kopecky. These lifestyle changes won’t actually change your LDL cholesterol because your high cholesterol is driven by genetics, Kopecky explains. However, living a healthy lifestyle does lower your cardiac risk by up to 80 percent, he says.

The AHA recommends eating fruits, vegetables, whole grains, poultry, fish, and nuts, and limiting sodium, added sugars, and red and processed meats. Additionally, you should get at least 150 minutes of moderate-intensity aerobic exercise a week—in the form of walking, running, cycling, swimming, or even yard work, according to the AHA. Kopecky warns against smoking as well.

Katz says it’s a good idea to keep up with cholesterol screenings every year or every other year—and to consider medication like statins—based on your individual risk level and family history.

A diagnosis of FH can actually be good news because it means you can ultimately prevent the dangers that high cholesterol poses. “In most cases, I consider high cholesterol treatable and a winnable battle,” Sarraju says.