At the risk of sounding like a certain 20-something socialite, HDL is hot! Advances in research have brought more attention to the blood lipid (or fat) we often call "good" cholesterol.
"Good" cholesterol doesn't refer to the cholesterol we eat in food, but to the high density lipoprotein cholesterol circulating in our blood. It's one of the blood fats measured in the lipid panel blood test doctors perform. And it's the component you want more of, because increasing HDL helps lower your risk of heart disease.
Experts of the National Cholesterol Education Program (NCEP) notes that although LDL or "bad" cholesterol has gotten most of the attention, there's growing evidence that HDL plays an important role.
Facts About "Good" Cholesterol
- HDL cholesterol normally makes up 20%-30% of your total blood cholesterol.
- There's is evidence that HDL helps protect against the accumulation of
plaques (fatty deposits) in the arteries.
- Research suggests that a five-point drop in HDL cholesterol is linked to a
25% increase in heart disease risk.
- In prospective studies - that is, studies that follow participants for a
certain period to watch for outcomes -- HDL usually proves to be the lipid risk
factor most linked to heart disease risk.
- HDL cholesterol levels are thought to have a genetic factor in some people.
- Women typically have higher HDL cholesterol levels than men. About a third of men and about a fifth of women have HDL levels below 40 mg/dL. Doctors consider levels of less than 40 mg/dL to be low.
Researchers from the Netherlands who analyzed 60 studies concluded that the ratio of total cholesterol to HDL (in which your total cholesterol number is divided by your HDL number) is a better marker for coronary artery disease than LDL measurement alone.
"Boosting HDL is the next frontier in heart disease prevention," says P.K. Shah, MD, director of cardiology at Cedars-Sinai Medical Center in Los Angeles. Shah says that if the new drugs designed to increase HDL levels prove effective, they could potentially reduce the number of heart attacks and strokes by 80% to 90% -- and save millions of lives. HDL-boosting drugs are now being tested.
How Does HDL Cholesterol Help Your Heart?
Experts aren't yet sure exactly how HDL cholesterol helps reduce the risk of heart disease. But a few possibilities have emerged.
The NCEP says that high HDL levels appear to protect against the formation of plaques in the artery walls (a process called atherogenesis), according to studies in animals.
Lab studies, meanwhile, suggest that HDL promotes the removal of cholesterol from cells found in abnormal tissues, or lesions, in the arteries.
"Recent studies indicate that the antioxidant and anti-inflammatory properties of HDL also inhibit atherogenesis," says the NCEP report.
Quick GuideLower Your Cholesterol, Save Your Heart
10 Ways to Increase HDL Cholesterol
What many people don't know is that some diet and lifestyle changes may help to increase HDL cholesterol levels.
Here are some of the contenders:
- Orange Juice. Drinking three cups of orange juice a day increased HDL
levels by 21% over three weeks, according to a small British study (at 330
calories, that's quite a nutritional commitment). This study could be
highlighting an effect from high-antioxidant fruits and vegetables. Stay tuned
in the years to come.
- Niacin. There is some evidence niacin (vitamin B3) helps increase HDL. Michael Poon, MD, chief of cardiology at the Cabrini Medical Center in New York, says people with low HDL levels might benefit from taking 500 milligrams of niacin each day, building up to 1,000 milligrams a day. But he warns that supplemental niacin "can have some side effects and is not for everybody, particularly for people who already have high HDL levels. "He says anyone taking niacin supplements should be monitored by a doctor. Short of supplements, many foods contain niacin as well. Here are a few:
Foods That Contain Niacin
|Food||Amount of niacin|
|White-meat chicken, 3.5 oz cooked||13.4 mg|
|Mackerel, 3.5 oz cooked||10.7 mg|
|Trout, 3.5 oz, cooked||8.8 mg|
|Salmon, 3.5 oz cooked||8 mg|
|Veal, 3.5 oz cooked||about 8 mg (ranges from 6.4-9.3)|
|Dark-meat chicken, 3.5 oz cooked||7.1 mg|
|Lamb, 3.5 oz cooked||6.6 mg|
|White-meat turkey, 3.5 oz cooked||6.2 mg|
|Ground beef, 3.5 oz cooked||5.3 mg|
|Peanuts, 1/4 cup||5.3 mg|
|Pork, 3.5 oz cooked||about 4.8 mg (ranges from 4.1-5.4)|
|Peanut butter, 2 tablespoons||4.4 mg|
|Beef steak, 3.5 oz cooked||about 4.1 mg (ranges from 3.6-4.5)|
- Glycemic Load. The glycemic load is basically a ranking of how much a
standard serving of a particular food raises your blood sugar. And as the
glycemic load in your diet goes up, HDL cholesterol appears to go down,
according to a small recent study. Along these lines, the NCEP report recommends
that most of our carbohydrate intake come from whole grains, vegetables, fruits,
and fat-free and low-fat dairy products. These foods tend to be on the lower end
of the glycemic scale.
- Choosing Better Fats. Replacing saturated fats with monounsaturated fats
can not only help reduce levels of "bad" cholesterol, it may also increase
levels of "good" cholesterol, according to the Food &
Fitness Advisor newsletter
from Cornell University's Center for Women's Healthcare.
- Soy. When substituted for animal-based products,
soy foods have heart
health benefits. Soy products are high in saturated fats and low in unsaturated
fats. Soy products are also high in
fiber. An analysis found that soy protein,
plus the isoflavones found in soy "raised HDL levels 3%, which could reduce
coronary heart disease risk about 5%," says Mark Messina, PhD, a nationally
known soy expert. Messina notes that soy also may lead to a small reduction in
LDL cholesterol and triglycerides (another type of blood fat), and a possible
enhancement in blood vessel function. Other studies have shown a decrease in LDL
cholesterol (about 3%) and triglycerides (about 6%) with about three servings of
soy a day. That adds up to 1 pound of tofu, or three soy shakes.
- Enough Time. Make sure you give soy some time. An analysis of 23 studies
on soy found that improvements in HDL cholesterol were only seen in those
studies lasting longer than three months.
- Alcohol in Moderation. Drinking moderate amounts of alcohol, especially
with meals, appears to do two things to help reduce heart disease risk.
According to researcher Byung-Hong Chung, PhD, it increases HDL cholesterol
levels, and enhances the movement of cholesterol deposits out of cells in the
- Aerobic exercise. At least 30 minutes on most days of the week is the
exercise prescription that can help raise your HDL, according to many health
- Stopping smoking. Experts agree that kicking the habit can increase your
HDL numbers a bit, too.
- Losing weight. Being overweight or obese contributes to low HDL cholesterol levels, and is listed as one of the causes of low HDL, according to the NCEP.
Environmental Nutrition, December 2005.
American Journal of Clinical Nutrition, 2005; vol 81; February 2005; September 2003; May 2003; and November 2000.
Final Report of the National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults) September 2002.
Evidence Report/Technology Assessment, Health & Human Services' Agency for Healthcare Research and Quality, August 2005.
Food & Fitness Advisor, Cornell University Center for Women's Healthcare, September 2002.
Prediman K. Shah MD, director of cardiology, Cedars-Sinai Medical Center, Los Angeles.
Michael Poon, MD, chief of cardiology, Cabrini Medical Center, New York. Mark Messina, PhD, adjunct associate professor, Nutrition Department, Loma Linda University; president, Nutrition Matters. Byung-Hong Chung, PhD, nutrition science professor emeritus, University of Alabama.
Reviewed by Robert J Bryg, MD on February 21, 2010
© 2010 WebMD, LLC. All rights reserved.
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