Spotlight on HDL
Produced by our bodies and absorbed from the food we eat, cholesterol is a waxy, fat-like substance that's vital for our brain function, hormone production, cellular activity -- every aspect of life.
When it comes to heart health, cholesterol is a double-edged sword. Most of us know by now that there are two main cholesterol carriers with very different roles. Low-density lipoproteins (LDL) transport cholesterol to the body's tissues and arteries. At high levels, LDL leads to plaque buildup in the arteries; this can lead to a sudden blockage or narrowing in an artery that may slow or stop blood flow to the heart (hence LDL's reputation as "bad" cholesterol). High-density lipoproteins (HDL), which carry cholesterol back to the liver to be removed from the body, protect against heart disease (and are thus called "good" cholesterol). "It's kind of the yin and the yang of atherosclerosis," says Superko. "Cholesterol is always being deposited in the artery and always being taken out."
Despite the fact that HDL's importance has been known for two decades, it's still upstaged by "bad" cholesterol. This isn't surprising, says Superko, since drugs to lower LDL are effective, and they bring in upwards of $20 billion to pharmaceutical companies each year -- creating a large incentive for further research and development, not to mention the ad campaigns. Drugs for raising HDL, on the other hand, have largely proven unsuccessful; clinical trials of one such drug, torcetrapib, were halted last year because it seemed to increase the risk of death.
Whereas until now the majority of data has revolved around LDL, that's changing, says Dr. Elsa-Grace Giardina, a cardiologist and director of the Center for Women's Health at Columbia University. "Recently we've seen that there are populations who have low 'good' cholesterol, and if you raise the good cholesterol in that population, you can actually make them live longer." Every 1-mg increase in HDL appears to correlate with a 2 percent to 3 percent drop in risk of heart disease -- similar to the results seen for every 1-mg decrease in LDL.
The Bottom Line
Both LDL and HDL are critically important for heart health. Your LDL-to-HDL ratio should be about 3.5 to 1, ideally, with an HDL level above 60 mg. And lifestyle is essential to both levels. Although dietary changes can help lower LDL, exercise and maintaining a healthy weight are key for raising HDL. In general, women tend to have higher HDL numbers than men, but postmenopausal women need to stay especially vigilant. "After you've gone through menopause, good cholesterol decreases," says Giardina. If you smoke, you can raise your HDL significantly just by quitting.
Rather than another prescription, the best pill for boosting HDL may be a vitamin. "Niacin (vitamin B3) is the most effective treatment at raising HDL," says Dr. Stephen Devries, preventive cardiologist at the Center for Integrative Medicine at Northwestern Memorial Hospital. Studies show that taking large doses (1 to 2 grams) of niacin daily can raise HDL by up to 30 percent. Because of potential side effects -- flushing, in which your skin turns red and you feel very warm, and liver problems -- it's essential to work closely with a doctor.
If only cholesterol were as simple as one hero and one villain. In fact, scientists have identified several types of LDL and HDL particles, along with other lipoproteins, like lipoprotein-a, or Lp(a). Physicians don't generally look this closely at their patients' cholesterol makeup, says Superko; because of a lack of standardization in labs, the tests aren't always reliable and aren't yet recommended for routine screening. But for high-risk individuals, especially those with a family history of heart disease, preventive cardiologists often recommend them.
LDL and HDL particles come in different sizes, from small, dense particles to lighter, larger particles (think marbles versus ping pong balls), with bigger particles being the healthiest. "Your cholesterol numbers can look good, but if your cholesterol is made up of the small particles, you could still be at risk," notes Devries. As for Lp(a), a 2006 study found that women who had very high levels as well as high LDL levels were at greater risk for heart disease than women with high LDL and low Lp(a).
The Bottom Line
For now, the take-away for most of us is the same as for any other aspect of cholesterol: Good numbers could belie hidden problems and are no excuse for neglecting other aspects of your health. If you have a family history of heart disease, talk to your doctor to identify your risks and determine whether you should consider additional lipid tests.
Among the most widely prescribed drugs in the world, statins are used by 10 percent to 15 percent of American adults over age 20. Although they have a good record for reducing heart attack and stroke risk, Devries notes that "they're never a complete solution." What's more, people with a lower risk of heart disease can often be treated with natural approaches, including diet, exercise, and, under a doctor's supervision, supplements. Superko says the glowing statistics on statins can be misleading. When you hear that in a study of 4,000 people, there was a 25 percent reduction in heart attacks due to statins, you might assume that 1,000 people were saved. But the 25 percent is actually a relative risk reduction, says Superko, meaning that of the patients who would have had a heart attack, 25 percent won't. If, for example, 400 people had heart attacks in the placebo group, then 300 had a heart attack in the statin group. In other words, 100 people -- not 1,000 -- were saved. "A 25 percent relative risk reduction with cholesterol-lowering alone helps a few people, but it misleads an awfully large number of people into thinking they're safe when they're not," he says.
The latest controversy surrounding statins is the new ultra-low levels recommended for people at high risk for heart disease -- levels difficult to attain without the use of prescription drugs. Whereas an LDL level below 100 was once considered optimal for those at high-risk, the new level to shoot for is 70. "However, you can't extrapolate that to everyone," notes Devries. "It doesn't mean that everyone should be at that level."
The Bottom Line
If you take statins, remember that they're no substitute for a healthy lifestyle. And talk to your doctor about a combination approach: Recent studies indicate that the relative risk reduction goes up to 90 percent when physicians combine statins that lower LDL levels with high doses of niacin, which raises HDL levels.
As research continues to develop, experts agree that heart health -- and heart disease -- encompass far more than cholesterol. Too often, people think if they control their cholesterol they have nothing else to worry about, says Dr. Mimi Guarneri, founder and medical director of the Scripps Center for Integrative Medicine. "But cholesterol is just a piece of the puzzle," she says.
The past decade has seen many studies showing the importance of conditions such as inflammation and insulin resistance, both of which increase your risk of heart disease, even independently of cholesterol levels.
Here, too, there's good news. The lifestyle "prescription" for healthy cholesterol levels -- to eat well, move often, and reduce stress -- improves many other heart-disease risk factors, too. And the benefits go on. A heart-healthy lifestyle "will not only help you live longer," says Devries, "but it will also help you lead a fuller, richer life."
Spotlight on HDL