There are two different kinds of cholesterol, sometimes referred to as “good” and “bad”. People are aware that too much “bad” cholesterol may be dangerous. What people may not know is that too little “good” cholesterol can also be dangerous. Knowing the difference between good and bad cholesterol is very important.
What Is “Bad” Cholesterol?
LDL (low-density lipoprotein) cholesterol is often referred to as “bad” cholesterol.
LDL cholesterol acts as a reckless taxi driver in the body. It picks up the cholesterol and drives it to the arteries and leaves it to adhere to the walls, thus forming plaque. These plaque formations eventually clog the arteries leading to heart attacks and strokes.
What Is “Good” Cholesterol?
HDL (high-density lipoprotein) cholesterol is considered good for your body because it carries cholesterol away from the arteries to the liver for elimination as bile acids thru the colon, referred to as “reverse cholesterol transport”. HDL contains an apolipoprotein subfraction, called apolipoprotein A1. The activity of apolipoprotein A1 helps retard atherosclerosis by preventing the fatty buildup of plaque on the arteries. This allows more blood flow thus reducing the incidence of heart attacks and strokes.
What Should My HDL Cholesterol Level Be
There is a high incidence of heart disease in individuals with low levels of HDL cholesterol. How low is too low? Levels of less than 35 mg/dl are definitely too low, but anyone whose HDL is below 55 should make every effort to raise it.
Four studies–the Prospective Cardiovascular Munster (PROCAM) Trial, Framingham, Tromso, and Honolulu Heart studies–reported an inverse relationship between concentrations of HDL cholesterol and CHD.
The Prospective Cardiovascular Munster (PROCAM) Trial focused on the importance of cholesterol in predicting the risk of heart attack. Study results showed that low HDL cholesterol is common among heart attack victims–nearly two thirds of men, aged 40 to 65 years, who had heart attacks in this study had a low level of HDL cholesterol. The PROCAM study found that low HDL cholesterol was the most pronounced risk factor and best predictor.
The world famous Framingham Heart Study was the first study to identify HDL cholesterol as a distinct, independent predictor of atherosclerotic cardiovascular risk. This divided participants into four categories based on their HDL. For both men and women, the highest rate of heart attacks occurred in the groups with the lowest HDL’s. This study also showed that HDL is inversely related to the development of MI, particular in women, and even in the presence of normal total cholesterol levels, low HDL increased risk of CHD.
The Tromso Heart Study supported indications that a low HDL concentration is an important factor in accelerating the progression of atherosclerosis.
The Honolulu Heart Study revealed a strong inverse pattern of coronary heart disease and stroke with optimal HDL cholesterol levels.
Can Increasing My Low HDL Make A Difference?
The landmark Helsinki Heart Study (HHS), found that every 1% increase in HDL cholesterol was linked to a 3% reduction in heart disease in patients with low HDL cholesterol and high LDL cholesterol.
The Framingham Heart Study in a control study showed that after one year both exercisers and dieters showed significant increases in HDL cholesterol compared with the control group. They concluded that the results provide evidence that weight loss through dieting or exercise is responsible for the elevations in HDL, thus reducing heart disease.
Women tend to have higher levels of HDL while their bodies are still ovulating. If women take estrogen when their bodies no longer produce it, their HDL levels tend to remain high. This is not reason enough for estrogen therapy; it is a highly individual decision that a patient and her doctor need to make together.
How Do I Raise My HDL
The same heart healthy advise applies as that used to lower total serum cholesterol:
- Stop smoking
Smoking not only increases your risk of heart disease and cancer, it raises the risk for those around you. If you stop smoking, your HDL will probably rise.
- Start exercise
Regular aerobic exercise will make you feel better, look better, and decrease your risk for diseases such as heart disease, diabetes, and obesity. A loss of body fat has been shown to increase levels of HDL cholesterol in obese patients. Exercise raises your HDL.
- Eat less fat
Lowering the total fat in your diet usually lowers your LDL, or bad cholesterol. When your LDL goes down, your HDL usually goes up.
- Control your weight
If you are above your ideal body weight, weight loss will probably increase your HDL.
- Ask your doctor
Drugs are a last resort. Drugs are not a substitute for a healthy lifestyle. The benefits of diet and exercise have positive effects on very aspect of your life.
Source: Lipid Digest, Vol. 1, Issue 3, DEC 1988. Parke-Davis Handout 1990