You have two main kinds of cholesterol. Low-density lipoprotein, or LDL cholesterol, is the sticky type that can attach to artery walls and clogs them up. High-density lipoprotein, or HDL, is the good kind of cholesterol that helps clean out your arteries.
Avoiding things that raise your LDL or lower your HDL cholesterol can help keep your levels in a healthy range. What you eat, how much weight you gain, your stress level, and lack of exercise are just a few of the things that can throw your numbers out of whack.
Food is the most obvious cause of unhealthy cholesterol levels. Your liver makes most of your body's cholesterol. But much of the cholesterol that you do get from your diet comes from foods that are high in saturated fats, such as:
- Red meat
- Whole milk and other full-fat dairy products
Trans fat is even worse for your heart. It both raises LDL cholesterol and lowers HDL cholesterol. This type of fat is so unhealthy that the FDA has banned it in the United States. But a few foods might still contain small amounts of trans fat, including cookies, cakes, crackers, and margarine.
People of any size can have high cholesterol, but it's more common when you're overweight.
Fat changes the way your body makes and removes cholesterol. Excess weight also slows its removal from your body.
Lack of Exercise
The chemicals in tobacco smoke damage blood vessel walls and make it easier for LDL cholesterol to stick to them. Smoking also lowers HDL cholesterol levels. It narrows blood vessels and thickens the blood, forcing your heart to work harder to pump enough blood out to your body.
A few chronic diseases cause too much inflammation in your body. At healthy levels, inflammation is your immune system’s natural response to injury or disease. In the short term, it helps your body heal. But when it continues long term, inflammation can lower your HDL cholesterol and raise your LDL.
All of these inflammatory conditions can affect cholesterol levels:
During pregnancy, your liver makes extra cholesterol to nourish your growing baby. By the third trimester, your cholesterol levels might be two to four times higher than they were before you got pregnant.
Cholesterol levels stay high for about a month after childbirth. Then they drop back down to prepregnancy levels.
If you started your pregnancy with low HDL and high LDL cholesterol, you could be at higher risk for pregnancy problems or heart disease later in life. It's important to work with your doctor to get your cholesterol levels into a healthy range before you try to get pregnant.
When you're under stress, your body releases cortisol, a hormone that can increase your cholesterol levels. Stress affects your cholesterol levels in other ways, too. Some people deal with stress by eating comfort foods, not exercising, or smoking, which all can affect cholesterol levels.
Type 2 Diabetes
Diabetes lowers HDL cholesterol. It can also increase LDL cholesterol, even if your blood sugar is under control. It also boosts levels of very-low-density lipoprotein, or VLDL, which carries a type of fat called triglycerides to your body’s tissues.
Some people have high LDL cholesterol because of their genes. Familial hypercholesterolemia (FH) is a condition that runs in families. FH makes it harder for your body to remove LDL cholesterol from your blood.
About 90% of people with FH don't know they have it. It’s a good idea to know your family history and have your doctor check your cholesterol levels regularly. Though you can't change your genes, you can control other risk factors.
Your Age and Gender
As you get older, your body can't remove cholesterol from your blood as well as it once could. That's one reason your risk for heart disease rises as you age.
Women tend to have lower LDL cholesterol and higher HDL cholesterol than men when they're younger. After menopause, their LDL levels rise.