Cholesterol has become a bad word in recent years, in large part because of its link with heart disease -- and there is definitely a connection. Too much cholesterol in your blood raises your risk of heart attack, stroke, and other problems.
But not all cholesterol is bad. There is so-called “good” cholesterol that your body needs to be healthy. And your cholesterol levels are only a piece of the puzzle that forms the picture of a healthy heart.
What We Know About Cholesterol and Heart Disease
Cholesterol is a waxy substance that you get from two sources -- your liver and the food you eat. It travels through the bloodstream in fatty bundles called lipoproteins. Low-density lipoprotein (LDL) cholesterol is the "bad" kind in your blood and can clog up your arteries, slow blood flow, and create dangerous blood clots. The higher your LDL levels, the higher your risk for heart disease.
But you also have high-density lipoprotein (HDL) or “good” cholesterol in your blood, which removes LDL and carries it back to your liver. A high HDL cholesterol level lowers your risk of heart problems.
But while cholesterol levels are generally a good measure of heart health, the relationship between them is not hard and fast. “In some people, high cholesterol doesn’t seem to have an effect,” says Alice Lichtenstein, spokesperson for the American Heart Association. “In general, we have a lot of data that if we reduce our LDL cholesterol, we reduce our risk of heart disease.” But, she says, there are other risks for heart disease.
Things We Can Control
Lichtenstein says one reason doctors single out our cholesterol levels as the key to heart health is that they’re something we can usually control through diet and exercise. “And it’s targeted for treatment because it’s the one we have drugs to treat,” she says. But there are other things that we have the power to change, too:
- Triglycerides. Often linked with cholesterol, these fats in the blood come from your food. They can cause a sticky buildup that can block your arteries.
- Smoking. Cigarette smoke not only raises cholesterol, but it forces your heart to work harder.
- Blood pressure. If it’s too high, it can make your heart muscles stiff.
- Obesity. Lichtenstein says that waist size in particular can make heart disease more likely, even in people with no other risks for heart disease.
- Physical inactivity. Regular exercise can lower blood pressure and strengthen your heart.
- Diabetes. Even if you have a grip on your blood sugar, having diabetes ups your chances of heart disease.
“We can’t really isolate single factors for heart disease,” Lichtenstein says. Many of them tend to overlap. People who are obese generally have higher triglyceride levels, lower HDL cholesterol levels, and a bigger waist.
What You Can’t Control
On top of all the ways you can try to stave off heart disease, there are a few risks that you are simply born with. They include:
- Gender. Men have a greater chance of having a heart attack, and at younger ages. For women, the risk of heart disease goes up after menopause.
- Age. The older you are, the greater your risk. Most people who die from heart disease are older than 65.
- Race. African-Americans, Native Americans, Mexican-Americans, and some populations of Asian-Americans seem to be at greater risk than whites.
- Family history. If your parents or grandparents had heart disease, you’re more likely to have it, too.
Even though there’s nothing you can do about these factors, it’s still good to know you have them. “For instance, if your family has a history of early heart disease, it’s important to have your levels of cholesterol measured at an early age,” says Donna Arnett, PhD, professor of epidemiology at the University of Alabama at Birmingham. “That way you can have it treated effectively.”
Changes to Your Genes
Beyond your family history of heart disease, there are other genetic signs that can mean you’re at high risk. Changes in certain genes can predict higher levels of cholesterol. Your doctor can also test your blood for proteins that have been linked to heart disease.
But Arnett, a former president of the American Heart Association, says that while these genetic signs help doctors recognize risk of heart disease, the research is still fairly new. “We are just now beginning to understand the genes that contribute to these conditions,” she says. “These blood tests are not widely available. In the near future -- 5 years, maybe -- we’ll have widely available tests that can see these markers. But in the meantime, knowing your family history and knowing your cholesterol levels is very important.”