According to the CDC, 2 in 5 adults in the US are living with high cholesterol, putting them at increased danger of serious health conditions such as heart attack and stroke. Not all cholesterol is the same—HDL cholesterol is good, LDL cholesterol is bad. “HDL is responsible for reverse cholesterol transport, which means it removes bad cholesterol from the bloodstream and takes it to the liver, which gets rid of it,” says Joe Miller III, MD, a cardiologist and expert in preventative medicine at Piedmont Heart Institute. LDL cholesterol leads to plaque buildup in the arteries, which can lead to coronary artery disease. “HDL is a vacuum cleaner and LDL is fuel for the fire.” An LDL level below 130 mg/dL is ideal, while an HDL level below 40 mg/dL for men, or 50 mg/dL for women, is considered low.

“So most people do not have genetically high cholesterol,” says cardiologist Leslie Cho, MD. “Most people get it the good old fashioned way, which is diet, which is lack of exercise, and also the whole beautiful process of aging. There are those of us that are genetically inclined to have high cholesterol. The worst case scenario is something called familial hypercholesterolemia, and people who have that have heart attacks at the age of 18 and they have LDL, the bad cholesterol, the lousy cholesterol, that are greater than 200 at a very, very young age. And those are people that we put on medicines aggressively because they tend to have very bad outcomes. 

“Now, some people can have something called the heterozygous FH. That means you have a milder version of that genetic cholesterol defect, and those people, their LDL is somewhere hanging out in the high one hundreds. So they can have somewhere around one seventies and above. And those people come to us usually in their 30s and 40s, because they’ve had a cholesterol screening from their job or when they were trying to get life insurance and they were astounded to find their cholesterol level so high.” While cholesterol levels can’t be diagnosed without a full lipid panel, there are certain factors strongly linked to dangerously high cholesterol. Read on—and to ensure your health and the health of others, don’t miss these Sure Signs You’ve Already Had COVID.

Smoking not only raises bad LDL cholesterol and makes it stickier (and therefore more dangerous), it also lowers good HDL cholesterol. According to Johns Hopkins Medicine, smokers are 2 to 4 times more likely to get heart disease and at doubled risk for having a stroke. “We know that smoking is a risk factor for cardiovascular disease and that cessation leads to decreases in cardiovascular disease and the risk of death,” says Dr. Mayank Sardana, a cardiac electrophysiology fellow at the University of California San Francisco School of Medicine. “But only a minority of smokers are receiving counseling in cardiology clinics and assistance in trying to quit.”6254a4d1642c605c54bf1cab17d50f1e

“My experience has been that for cardiologists, tobacco has sort of been the forgotten risk factor,” says Dr. Nancy Rigotti, a professor of medicine and internist at Harvard Medical School and Massachusetts General Hospital. “They’re aggressive about taking care of high cholesterol and high blood pressure, and we have medicines that are very effective for that. But with smoking cessation it’s more of a chronic problem that takes a long time to work. It’s not a simple fix… Someone who has newly diagnosed heart disease or just had a heart attack may be scared and willing to make behavioral changes that maybe they didn’t think they needed to do before.”

Lack of exercise can impact cholesterol levels, doctors say. “Exercise can definitely impact your cholesterol level, especially your HDL and your triglycerides,” says Dr. Cho. “It has a dramatic impact on your good cholesterol and your triglyceride. Exercising is amazing for your blood pressure, which is an important, important risk factor. Exercising has a dramatic impact on whether you get diabetes or not, another amazing benefit of exercise. Most people, most societies, so American Heart Association, the American College of Cardiology recommend that you get about 30 minutes most days of the week. Now, that number seems like a ridiculously high number for those of us that don’t exercise. But what I want everyone to remember is that you don’t start at 30 minutes. You start maybe at five minutes, and you do what you can. And then maybe in two weeks, you go to 10 minutes.”

According to Dr. Cho, you don’t need to join a gym or even do “regular” workout sessions—just make a point to be as active as possible. “Maybe exercising means you get off one floor before your destination off the elevator and walk up that extra flight of stairs,” she says. “Maybe it means parking further away and you walk rather than try to fight for the nearest parking spot at work. These little things make a very big difference. But exercise, we always think of exercises as yet another chore in our very, very busy day, but it really has an amazing, amazing benefit. And if we can bottle exercise and sell it, it would be the best, best, the most effective pill that we’ve ever made.”

Sugar is strongly linked with lowering good cholesterol and making LDL cholesterol worse. “Standard cholesterol measurement reveals your total cholesterol level broken down by LDL (bad cholesterol), HDL (good cholesterol) and triglycerides,” says Spencer Kroll, MD, PhD. “LDL elevation, which is linked in part to saturated fat intake, is only one type of cholesterol problem. How is sugar a major culprit in cholesterol problems? Eating sugar and other carbohydrates raises triglycerides and lowers HDL. It also causes dysfunctional alterations in LDL molecules. LDL levels may seem normal, but this dysfunctional LDL can cause rapid clogging of arteries and increased risk for thrombosis.”

Dr. Kroll recommends anyone worried about their cholesterol levels to be mindful of their sugar and refined carbohydrate intake. “Generally speaking, the goal for many people is to reduce daily sugar intake and realize that carbohydrates must also be reduced to impact your cholesterol problems,” Dr. Kroll says. “Avoid high fructose corn syrup. The brain cannot sense this form of sugar like it does regular table sugar and this will cause you to eat more before feeling full. After about five days of living on fewer carbohydrates, my patients report feeling much more energy, less stress and even craving healthier food choices. So give your body a gift that will keep on giving. Dump the sugar and reduce the carbs. Your cholesterol, heart, mind and body will thank you for it.”

It’s important to understand that eating foods high in cholesterol (for example eggs) does not lead to high cholesterol. “However, people with certain health problems, such as diabetes, should continue to avoid cholesterol-rich foods,” says cardiologist Steven Nissen, MD. Dr Nissen recommends avoiding foods high in trans fats. “Those often appear on food labels as hydrogenated oils or partially hydrogenated vegetable oil,” he says. “Those types of fats do tend to raise cholesterol and do tend to increase the risk of heart disease.”

What about saturated fat? “Saturated fat is a bigger culprit for raising blood cholesterol in general than dietary cholesterol,” says Dr. Stephen Devries, a preventive cardiologist and executive director of the educational nonprofit Gaples Institute in Deerfield, Illinois. “The risk of every dietary factor has been in turns both exaggerated and other times minimized, and that’s definitely the case with saturated fat. If saturated fat is replaced with refined carbs, like sugar or white bread, then there’s been shown to be no net health benefit. If saturated fat is replaced with other healthier fats, then there’s a clear health benefit with a lower rate of heart disease. It’s most important to focus on the categories of healthful foods, rather than discussing individual nutrients like saturated fat or cholesterol. Most people don’t look at (nutrition) labels and what I’m trying to encourage people to do is to eat more food that doesn’t have labels.”

Obesity is strongly linked to high LDL cholesterol, experts warn—but the good news is by losing weight, you can bring cholesterol levels down. “[Obesity] can change your cholesterol levels,” says Penn Medicine. “Most of us know that obesity can cause a spike in bad cholesterol and triglyceride levels, but did you know it can also lower good high-density lipoproteins (HDL) cholesterol? HDL cholesterol is important for removing bad cholesterol and working to reduce the risk for heart disease.”

“If you lose weight, your HDL will go up and your LDL will come down. Now, probably the total cholesterol, if you lose like the 5-10 pounds can be lower by about 5%-10%,” says Dr. Cho. “Most of us are carrying extra weight. And if you lose around five to 10 pounds, you can have a dramatic impact on your blood pressure, your risk of diabetes, and your cholesterol level. It really does make a dramatic impact… And if we think about diet, we go on these restrictive diets and once we stop the diet, we gain weight and it’s like a yoyo—actually yo-yoing is really bad for your body, because it really does mess up your metabolism. It really has an adverse effect on your metabolism. But if you can try to think of it as making not a diet, but lifestyle modification changes, where you start eating more healthy, exercising just a little bit more, I think that’s a better way to think about ‘diet.’ We usually recommend losing one pound a week.”