When it comes to total cholesterol and LDL (the "bad" type of cholesterol), having extremely high levels can mean serious risk for early heart attack and stroke. Read on to discover how high cholesterol levels can actually go, what causes this and what you can do about it.
Read more: What You Need to Know About Cholesterol
Video of the Day
The Lowdown on High Cholesterol
"I would say that there is probably no upper end" for cholesterol levels, says cardiologist Eugene Yang, MD, MS, a cardiologist and professor of medicine at the University of Washington, Bellevue.
Usually, he says, very high cholesterol levels occur in people who have an inherited condition called familial hypercholesterolemia (FH). "In those patients, you can have total cholesterol levels that are over 1,000," Dr. Yang says. "And you can have those patients who have LDL, or 'bad cholesterol,' levels of over 500."
According to the FH Foundation, a genetic mutation makes it difficult for the bodies of people with FH to remove low-density lipoprotein (LDL) from their bloodstreams. LDL can build up on artery walls, causing atherosclerosis (sometimes referred to as hardening of the arteries), which can lead to a heart attack or stroke.
Because of their higher cholesterol levels, people with FH develop heart disease at much younger ages. Without treatment, the American Heart Association (AHA) says, men with FH will get coronary heart disease up to 20 years earlier than normal, while women with FH will get coronary heart disease up to 30 years earlier.
"With patients who have very high cholesterol levels — close to 1,000 — we will see those individuals have heart attacks before the age of 20," says Dr. Yang. "So, it's very dangerous, and it's something that needs immediate involvement by a cardiologist or somebody who specializes in treating lipid disorders."
The good news is that FH is treatable. As the FH Foundation notes, lowering cholesterol levels can help prevent or slow heart disease. While the diet and lifestyle measures typically recommended for lowering cholesterol levels play a role, they aren't enough for people with FH. Cholesterol-lowering medications known as statins are a mainstay of treatment, and many people with FH take more than one type of medication.
Children can be started on cholesterol-lowering medication as young as age 8 or 10, according to the AHA. For people with a rare and more severe form of FH, advanced treatment may include apheresis, a procedure similar to dialysis in which LDL cholesterol is removed from the blood.
Other Causes of High Cholesterol
While extremely high cholesterol levels are typically a sign of FH, Dr. Yang says there have been cases where eating habits have been the cause — particularly since the growth in popularity of ketogenic diets for weight loss.
"Individuals are eating lots of red meat, saturated fat from dairy products and avoiding simple carbohydrates," he says. "And we have seen, in isolated cases, individuals having cholesterol levels that approach 800 or 900 — so they're similar to what we see in patients who have familial hypercholesterolemia."
If tests show you have extremely high cholesterol levels and you're following this kind of diet, Dr. Yang recommends that you let your doctor or health care provider know what you've been eating.
Healthy Cholesterol Levels
"In general, the lower LDL (bad cholesterol) and total cholesterol, the better — there's no doubt about that," says Dr. Yang. But he adds that "it's very hard to say specific age-related levels."
Instead, he says, doctors use what they call risk-stratification tools. These take a number of factors — including your age, your cholesterol and your blood pressure — and calculate what your risk is of having a heart attack or stroke. "Based on that, we can decide what an optimal level of cholesterol level is and whether treatment with medication is necessary," he says.
The AHA endorses this approach, saying cholesterol levels should be considered as part of the overall picture of your heart disease risk. Your doctor can evaluate your specific risks and make recommendations that are best for you.
- Eugene Yang, MD, MS, cardiologist, internal medicine, professor of medicine, University of Washington, Bellevue
- FH Foundation: “What Is Familial Hypercholesterolemia?”
- American Heart Association: “Familial Hypercholesterolemia (FH)”
- FH Foundation: “FH Treatments”
- American Heart Association: “What Your Cholesterol Levels Mean”
Is this an emergency? If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911.