Most people who have undesirable cholesterol levels and can’t improve them sufficiently via diet and exercise are prescribed statin drugs. But there’s also a vitamin, niacin—known as B3—that in very large doses can improve cholesterol levels and reduce the risk of heart attacks. When niacin’s beneficial effect was discovered in 1955, it became the first treatment for high cholesterol.
Who wouldn’t prefer to take a vitamin over a prescription drug, you might ask. But it’s not that simple. Though classified as a dietary supplement, high-dose niacin, in effect, is a drug, whether you buy it over the counter or by prescription. And like any drug, it has potential side effects and should be taken under medical supervision. In addition, there are different forms of niacin on the market, which vary in effectiveness and risks, so shopping for it in the health-food store or drugstore can be confusing.
What’s more, niacin’s anti-cholesterol credentials were tarnished in May 2011, when disappointing results from a major study were released, making some people wonder if they should stop using niacin (see box below).
Here are answers to some questions you may have.
What are niacin’s benefits?
The main goal of cholesterol treatment is to lower LDL (“bad”) cholesterol. Statins do this much better than niacin does. But niacin has the advantage of raising HDL (“good”) cholesterol much more than statins do. It also lowers triglycerides, fats in the blood that can increase the risk of heart disease. For these reasons, niacin may be a good option for people who can’t tolerate statins well and for those who have very low HDL and/or high triglycerides. Moreover, niacin helps people who have elevated levels of small, dense LDL particles, which increase coronary risk.
What are the risks of high-dose niacin?
The chief problem is that it often causes intense flushing (mostly on the face and upper body). This is not harmful or long-lasting, but many people find it hard to put up with and thus stop taking the pills. The flushing usually decreases with continued use. Niacin can, in rare cases, cause liver damage. It can raise blood sugar slightly, but is considered safe for people with diabetes. It can also increase the risk of gout and flare-ups of peptic ulcer disease.
What are the different forms of niacin?
The form that improves cholesterol levels is called nicotinic acid. The standard dose for treating cholesterol is 1 to 3 grams daily, 50 to 150 times more than what’s in a basic multivitamin. But you’ll also find other forms for sale, such as niacinamide and inositol hexanicotinate, which have little or no effect on cholesterol.
In addition, there are three categories based on the rate of release of the niacin:
• Immediate-release niacin is effective and least expensive, but causes more flushing. It has to be taken two or three times a day.
• Sustained-release/extended-release niacin causes less flushing. However, some over-the-counter formulations may be less effective and increase the risk of liver toxicity. The extended-release form sold by prescription (Niaspan is the best-known brand) is effective, least likely to cause in¬¬tense flushing and safer for the liver—but it costs even more than brand-name statins. An over-the-counter sustained-release preparation called Slo-Niacin is similar to Niaspan but much less expensive.
• No-flush niacin (inositol hexanicoti¬¬nate) has no “free” nicotinic acid, so it has little or no effect on cholesterol. Still, some labels say “supports normal cholesterol.”
How can you reduce the flushing?
Besides taking an extended-release product, take niacin with food—preferably after dinner or a bedtime snack. Avoid hot drinks or alcohol near the time you take niacin. Also, take aspirin (or a related drug, such as ibuprofen or naproxen) before the meal; even a “baby” aspirin may help. But check with your doctor before taking aspirin regularly, since it is contraindicated for some people.
Bottom line: Statins remain the first-line choice because they are most effective at lowering LDL, are proven to prevent heart attacks and rarely cause side effects. If you also have low HDL and/or high triglycerides, you and your doctor may decide to add niacin to your regimen. Talk to your doctor or pharmacist about the various forms, and take niacin under medical supervision. As with other cholesterol-lowering drugs, you’ll need to be monitored to make sure it is achieving the desired re¬¬sults and isn’t harming your liver.
Niacin + statin = surprising results
Doctors often prescribe both a statin and niacin when either drug by itself fails to have sufficient effect, or when patients have low HDL and/or high triglycerides as well as high LDL. The combination improves cholesterol levels more than either drug alone, but it has not been clear whether it is better at preventing heart attacks than a statin alone.
Preliminary results from a long-awaited federal study have now called into question the notion of adding niacin to statin therapy—at least in some people. The study, called AIM-HIGH, was halted early and has not been published yet; only sketchy data have been released.
The study involved 3,400 people with a history of cardiovascular disease who were already taking a statin to lower their LDL but still had low HDL and high triglycerides. Their statin doses were adjusted so they achieved the LDL target of less than 80. Some subjects were then also given high-dose extended-release prescription niacin (Niaspan), with the expectation that it would offer extra protection by raising HDL and lowering triglycerides.
The study was stopped after 32 months when, surprisingly, it became clear that the combination group, despite its higher HDL levels, did not have fewer heart attacks or other cardiovascular events than the statin-only group—and had slightly more strokes.
If you are taking niacin, don’t stop because of this study, at least not without consulting your doctor. This was a select group of older patients with existing coronary heart disease who had already achieved very low LDL levels. It’s possible that once LDL is so low, raising HDL may not matter much—that is, there may be little room for further reduction in cardiac risk. Niacin may still provide added benefits for people with a different risk profile or those who have not reduced their LDL level so dramatically. Moreover, none of the previous studies on niacin found an increased risk of stroke, and many experts believe this was a statistical fluke in the new study.
A much larger study of a niacin/statin combination is now underway and the results may clarify matters. Results are expected in 2013.
Source: Berkeley Wellness Letter December 2011
http://www.wellnessletter.com/ucberkeley/dietary-supplements/niacin-for-cholesterol-an-update/#
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