Boosting your "good" HDL cholesterol is not as easy as lowering LDL cholesterol, but there are a number of ways to make a modest improvement. HDL cholesterol of less than 40 mg/dL increases cardiovascular risk independent of levels of LDL cholesterol. For example, the Framingham Heart Study suggests that every 1 mg/dL increase in HDL cholesterol reduces the risk of cardiovascular disease by 2% to 3%. Strategies for raising HDL levels fall into three main categories—nonpharmacological (lifestyle changes), pharmacological, and novel.
Lifestyle changes are the mainstay for raising HDL cholesterol. Exercise should be your first move. According to a 2008 review article in the journal Heart, aerobic exercise can elevate HDL cholesterol levels by 5% to 10%, with the increase related to the frequency and intensity of the exercise. Men with low HDL cholesterol, high triglycerides, and abdominal obesity gain the greatest benefit.
Stopping smoking can also raise HDL levels. While smoking reduces HDL cholesterol, quitting can increase it by 4 mg/dL. According to the Framingham study, former smokers have HDL cholesterol levels similar to those of nonsmokers.
Weight loss is especially important in people with abdominal obesity associated with metabolic syndrome. Studies cited in the Heart review demonstrate that a weight loss of about 22 pounds can increase HDL cholesterol levels by 20%. Dietary changes can improve your HDL cholesterol in other ways too; for instance, increasing intake of omega-3 fatty acids or going on a low-carbohydrate diet.
If you like a drink of wine, beer, or spirits now and then, it's good to know that mild to moderate drinking can elevate HDL cholesterol by 9 to 13 mg/dL, but stay within the guidelines of no more than one drink per day for women and two for men (see "Alcohol and heart disease").
When it comes to medication, niacin is the most effective option for raising HDL cholesterol. Niacin can raise HDL levels by 15% to 35%. But make sure to ask your doctor for the prescription version, which has fewer side effects than over-the-counter options.
Statin drugs have generally been found to have only a moderate effect on HDL, but in the ASTEROID trial, treatment with rosuvastatin raised HDL cholesterol by the largest margin yet seen, 14.7%. In the AFCAPS/TexCAPS trial, lovastatin increased it by 6% in patients without heart disease. This finding was associated with a 37% reduction in risk for a first major coronary event.
Bile acid binders in high doses can lower LDL cholesterol significantly, but have only a minor effect on HDL cholesterol (5%). Ezetimibe has a similar small effect on HDL cholesterol, raising it by 5%. That number, however, may be increased by combining the drug with a statin or fibrate. That said, the AIM-HIGH study showed that even though niacin and a statin taken together did increase HDL cholesterol and decrease triglycerides more than a statin alone did, the combination did not affect heart attack and stroke risk in a group of people who already had low LDL levels (see "Drug combinations").
Novel strategies. Several novel approaches to raising HDL are being developed. Efforts to augment levels of apoA1, the protein carried by HDL cholesterol, are under way. One possible approach in people with severe heart disease is intravenous administration of a synthetic form of a particular type of apoA1, called apoA1 Milano. Data indicate that apoA1 Milano can raise HDL levels and reverse atherosclerosis. Other potential ways to increase HDL cholesterol under study include the use of peptides that mimic the benefits of apoA1.
Research into CETP inhibitors (see "HDL cholesterol") is also continuing despite the failure of torcetrapib to safely increase HDL levels. Several reasons for that outcome have been suggested, and there is speculation that the problem was limited to torcetrapib rather than the whole class of drugs.
Two other CETP inhibitors, anacetrapib and dalcetrapib, are now well along in clinical trials, though not yet approved by the FDA. These drugs do not have the adverse blood pressure effect that torcetrapib had, but they do significantly lower LDL cholesterol and raise HDL. Both drugs will have to show that they actually improve cardiovascular health before the FDA will approve them, so it remains to be seen if they will ever reach the pharmacy.