In general, you want low cholesterol -- the lower, the better. HDL, however -- commonly called "good" cholesterol -- should be as high as possible. In fact, if your HDL levels are too low, you're at increased risk for heart disease. There are some things you can do to raise dangerously low HDL.
Cholesterol
In common parlance, there are two "types" of cholesterol -- good and bad. The reality, however, is that there's only one kind of cholesterol, but there are two types of cholesterol transporter particles. "Good" cholesterol is HDL, or high-density lipoprotein, while "bad" cholesterol is LDL, or low-density lipoprotein. Both are particles made up of cholesterol and other kinds of fats, plus many types of protein, according to Drs. Reginald Garrett and Charles Grisham in their book "Biochemistry."
HDL
Even though it's unhealthy for your heart to have a high cholesterol level, you actually want high HDL. This is because the HDL transporter particle carries excess cholesterol out of the body cells and back to the liver for excretion. HDL is essentially a cholesterol removal system, and the more you have, the better. The American Heart Association recommends that your HDL be higher than 60 mg/dl of blood.
Low HDL
If your HDL is low -- less than 50 mg/dl for women, or 40 mg/dl for men -- you're at increased risk of cardiovascular disease, according to the American Heart Association. This is true even if your other cholesterol levels -- LDL and triglycerides -- are low, which they should be. Heart conditions you're at risk for include atherosclerosis, which is hardening of the arteries, as well as arterial narrowing. You're additionally at risk for heart attack and stroke.
Raising HDL
If your HDL is dangerously low, there are a few things you can do to increase it. The single most effective way to increase your HDL is to exercise regularly. Moderate alcohol consumption also increases HDL -- one drink per day for women, and one to two drinks per day for men. You should also avoid saturated and trans fats -- these can decrease your HDL, while plant-based oils like olive oil do not.
References
- "Biochemistry"; Reginald Garrett, Ph.D. and Charles Grisham, Ph.D.; 2007
- American Heart Association: HDL
