LDL and HDL are both lipoproteins; they’re made up of fat (lipid) and proteins. LDL is low-density lipoprotein, and HDL is high-density lipoprotein. Since good and bad cholesterol can’t dissolve in blood, lipoproteins carry it to and from your cells. This cholesterol is made by your liver and also comes from the food you eat.
We hear a lot of bad things about cholesterol, but our bodies actually need some of it. Cholesterol helps produce hormones, cell membranes, vitamin D and bile acids, which help digest fat. Both HDL and LDL, as well as triglycerides, have different effects on your body.
This “bad” cholesterol can damage the thin layer of cells that line your arteries. These blood vessels carry blood from the heart throughout your body. After the layer of cells is damaged, LDL enters the wall of the artery. White blood cells also enter, trying to digest the LDL.
This combination of cells and LDL accumulates over time, forming plaque— a thick, hard deposit—that clogs arteries and makes them less flexible.
When blood isn’t allowed to flow freely, it causes serious health problems. If a clot forms and blocks a narrowed artery, you could have a stroke or heart attack. Heart attacks are unpredictable, but if your LDL is too high, your risk of having heart disease increases.
Plaque can also cause peripheral artery disease if an artery that supplies blood to one of your legs becomes partially blocked. Depending on the degree of blockage, you could develop pain, sores, and have difficulty walking. If circulation is totally blocked, you could eventually lose your limb.
Your doctor will take into account a variety of factors to determine where your LDL levels should be. These will help him or her gauge your risk of having a heart problem or stroke. Several factors, such as high blood pressure and smoking, can raise your risk of heart disease. Generally, most people should try to have an LDL level below 130 milligrams per deciliter (mg/dL).
Your doctor will help you develop a plan to lower your LDL. This may include one or more of the following:
- Diet: You’ll need to lower the amount of saturated fat you eat.
- Exercise: Regular exercise not only lowers LDL, but also raises HDL.
- Medication: One or more medicines can be prescribed if needed.
This “good” cholesterol performs several important functions:
- It removes some of the LDL.
- It helps keep the walls of your arteries free from plaque.
- It takes some of the LDL back to the liver, where it can be broken down and removed from your body.
If you have a healthy level of HDL, you’ll be somewhat protected against heart attack and stroke, since your arteries will be less vulnerable to plaque and clots. If you have a low level of HDL, however, your risk of developing heart disease grows.
HDL levels greater than 80 milligrams per deciliter (mg/dL) are considered good. Anything lower than 40 mg/dL is considered low.
You can increase your HDL level in the following ways:
- Exercise: Get moving for at least 30 minutes for five or more days a week.
- Stop smoking: Smoking lowers HDL levels.
- Maintain healthy weight: This not only improves your HDL levels, it independently helps reduce your risk of heart disease.
Your body converts calories that it doesn’t need right away into triglycerides. These fats are stored in your blood until your body needs them for energy between meals. Too many calories, as well as a high number of calories from carbohydrates and fats, can make your triglyceride levels high. This can raise your overall cholesterol level and your risk of heart disease.
Triglyceride levels below 150 mg/dL are considered normal. Borderline high is 150-199 mg/dL, high is 200-499 mg/dL, and anything above that is very high.
The following lifestyle changes often are very effective at bringing your numbers down:
- Diet: Avoid simple carbohydrates like sugar. Limit saturated fats in your diet, such as whole-milk products, ice cream, high-fat meats, lard and hydrogenated or partially hydrogenated oils.
- Weight loss: If you’re overweight, losing just five to ten pounds can help.
- Exercise: Aim for 30 minutes a day most days of the week.
Work with your doctor and healthcare team to address your specific good and bad cholesterol and triglyceride issues.