When it comes to cholesterol, most people think lower is better. But it isn’t so simple. While all the cholesterol you eat is the same, cholesterol in the blood travels in different types of packages. The two basic kinds are LDL (low-density lipoprotein, the "bad" type), which promotes atherosclerosis, and HDL (high-density lipoprotein, the "good" type), which helps protect against this. So while you want to keep your LDL and total cholesterol low, you want to keep your HDL high.
HDL is turning out to be even more cardio-protective than previously thought. Not only does it help remove cholesterol from artery walls, but recent research indicates that it also acts as an antioxidant, reduces inflammation and blood clotting, and helps blood vessels to dilate and stay flexible. Low HDL is a part of the metabolic syndrome, a cluster of conditions that greatly increases the risk of heart disease, stroke, and Type 2 diabetes.
It’s estimated that for every 1 mg/dl increase in HDL, the risk of cardiovascular disease drops by 2 to 3%. Low HDL is now considered as important an indicator of cardiovascular risk as high LDL. In fact, if you’re over 70, HDL may be an even stronger indicator than LDL, according to a study in Circulation in 2005. Women tend to have higher HDL than men, since estrogen raises it. Low HDL for women is thus defined as less than 50 mg/dl (1.3 mmol/L), while for men it is less than 40 mg/dl (1.0 mmol/L). HDL over 60 mg/dl (1.6 mmol/L) is considered protective, even though it adds to your total cholesterol reading. (Note: in the U.S. cholesterol is measured in milligrams per deciliter [mg/dl] of blood; in Canada and most other countries, in millimoles per liter [mmol/L].)
For all these reasons, drug companies have turned their attention to the development of new drugs to raise HDL, having had great success with medication (notably statins) that lowers LDL. Though Pfizer had to halt a major study on a promising HDL booster in December because it actually increased death rates, other drugs are still being tested.
What you can do
Your HDL level depends primarily on your genes. It’s harder to increase HDL than to lower LDL. Unfortunately, some measures modestly.
• Lose weight if you’re overweight. Losing weight by exercising and cutting calories is more likely to help than losing it only by dieting. This is especially important if you carry most of your excess weight in your abdomen (that is, your body is apple-shaped). For every 10 pounds of weight lost, HDL rises 2 mg/dl, on average, according to one analysis.
• Don’t smoke. Smoking lowers HDL by an average of 5 mg/dl. Even secondhand smoke lowers it.
• Consider a drink a day. Alcohol can raise HDL, especially the larger, more beneficial particles. But keep your intake moderate: no more than one drink a day for a woman, two drinks for a man. Alcohol has health risks, so most people shouldn’t start drinking for the potential cardiovascular benefits. In addition, many people with low HDL also have high triglycerides, and alcohol can increase the level of these fats in the blood.
• Limit your intake of starchy or sugary foods, as well as trans fat. Instead, eat more high-fiber foods and healthy fats, such as omega-3s (in fish) and monounsaturates (as in nuts and olive or canola oil), along the lines of a Mediterranean diet. A recent review of 27 studies, published in the American Journal of Cardiology, confirmed that omega-3s can boost HDL. And several studies have shown that various nuts can do so, too.
• Talk to your doctor about medication, if necessary. Several drugs, notably high-dose niacin, boost HDL significantly, and more powerful ones are on the horizon. Statin drugs help maintain HDL or raise it modestly—usually by no more than 5 to 10%. For some people, it may take two drugs to lower LDL and raise HDL sufficiently.
• Avoid dietary supplements that claim to raise HDL. While some studies suggest that arginine, red rice yeast, guggulipid, garlic, and policosonal, for instance, can raise HDL levels, the evidence is mixed, and any effect is likely to be small. Some supplements, such as HDL Booster, contain a variety of such compounds, plus vitamins and minerals. There are no published studies on these formulas, and you have no idea what you’re getting, other than wishful thinking.
And by the way: HDL varies in size, and the larger the particle, the more protective it is. If you are at high risk for heart disease, your doctor may want to measure the size of your HDL as well as LDL particles, though such testing is not routinely used.
UC Berkeley Wellness Letter, February 2007
HDL is turning out to be even more cardio-protective than previously thought. Not only does it help remove cholesterol from artery walls, but recent research indicates that it also acts as an antioxidant, reduces inflammation and blood clotting, and helps blood vessels to dilate and stay flexible. Low HDL is a part of the metabolic syndrome, a cluster of conditions that greatly increases the risk of heart disease, stroke, and Type 2 diabetes.
It’s estimated that for every 1 mg/dl increase in HDL, the risk of cardiovascular disease drops by 2 to 3%. Low HDL is now considered as important an indicator of cardiovascular risk as high LDL. In fact, if you’re over 70, HDL may be an even stronger indicator than LDL, according to a study in Circulation in 2005. Women tend to have higher HDL than men, since estrogen raises it. Low HDL for women is thus defined as less than 50 mg/dl (1.3 mmol/L), while for men it is less than 40 mg/dl (1.0 mmol/L). HDL over 60 mg/dl (1.6 mmol/L) is considered protective, even though it adds to your total cholesterol reading. (Note: in the U.S. cholesterol is measured in milligrams per deciliter [mg/dl] of blood; in Canada and most other countries, in millimoles per liter [mmol/L].)
For all these reasons, drug companies have turned their attention to the development of new drugs to raise HDL, having had great success with medication (notably statins) that lowers LDL. Though Pfizer had to halt a major study on a promising HDL booster in December because it actually increased death rates, other drugs are still being tested.
What you can do
Your HDL level depends primarily on your genes. It’s harder to increase HDL than to lower LDL. Unfortunately, some measures modestly.
• Lose weight if you’re overweight. Losing weight by exercising and cutting calories is more likely to help than losing it only by dieting. This is especially important if you carry most of your excess weight in your abdomen (that is, your body is apple-shaped). For every 10 pounds of weight lost, HDL rises 2 mg/dl, on average, according to one analysis.
• Don’t smoke. Smoking lowers HDL by an average of 5 mg/dl. Even secondhand smoke lowers it.
• Consider a drink a day. Alcohol can raise HDL, especially the larger, more beneficial particles. But keep your intake moderate: no more than one drink a day for a woman, two drinks for a man. Alcohol has health risks, so most people shouldn’t start drinking for the potential cardiovascular benefits. In addition, many people with low HDL also have high triglycerides, and alcohol can increase the level of these fats in the blood.
• Limit your intake of starchy or sugary foods, as well as trans fat. Instead, eat more high-fiber foods and healthy fats, such as omega-3s (in fish) and monounsaturates (as in nuts and olive or canola oil), along the lines of a Mediterranean diet. A recent review of 27 studies, published in the American Journal of Cardiology, confirmed that omega-3s can boost HDL. And several studies have shown that various nuts can do so, too.
• Talk to your doctor about medication, if necessary. Several drugs, notably high-dose niacin, boost HDL significantly, and more powerful ones are on the horizon. Statin drugs help maintain HDL or raise it modestly—usually by no more than 5 to 10%. For some people, it may take two drugs to lower LDL and raise HDL sufficiently.
• Avoid dietary supplements that claim to raise HDL. While some studies suggest that arginine, red rice yeast, guggulipid, garlic, and policosonal, for instance, can raise HDL levels, the evidence is mixed, and any effect is likely to be small. Some supplements, such as HDL Booster, contain a variety of such compounds, plus vitamins and minerals. There are no published studies on these formulas, and you have no idea what you’re getting, other than wishful thinking.
And by the way: HDL varies in size, and the larger the particle, the more protective it is. If you are at high risk for heart disease, your doctor may want to measure the size of your HDL as well as LDL particles, though such testing is not routinely used.
UC Berkeley Wellness Letter, February 2007
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