Apr 10, 2013
Vitamin B3—also called niacin or nicotinic acid—has been safely used for 60 years to control cholesterol, with some 42,000 scientific papers in PubMed describing its benefits and effects.
“Unlike statin drugs, which mainly reduce LDL cholesterol, niacin is a very safe, effective treatment for all lipid issues, improving levels of both good and bad cholesterol and triglycerides, ” says Bradley Bale, MD, medical director of the Heart Health Program for Grace Clinic in Lubbock, Texas.
One landmark study published in Journal of the American College of Cardiology found that at therapeutic doses, niacin boosted HDL by up to 35 percent and cut triglycerides by as much as 50 percent.
Most remarkably, when the researchers tracked the 8,431 participants—all of whom had suffered heart attacks prior to enrolling in the study—for 15 years, those on niacin had a 26 percent lower risk for both heart attacks and strokes, even after treatment was discontinued, compared to those taking a placebo.
Highly Effective, But Often Overlooked
Despite some 42,000 scientific papers in PubMed describing niacin’s effectiveness and medical uses, it’s remained the ugly duckling of heart medicines, for a variety of reasons.
“The simple answer is to follow the money,” contends OMNS. “Cholesterol-controlling drugs [such as statins] are cash cows for the trillion-dollar-per-year pharmaceutical industry,” while there’s no marketing push to persuade medical providers to recommend a cheap, OTC remedy like niacin.
In his practice, Dr. Bale typically recommends niacin for the following patients, if medically appropriate:
- People with high cholesterol who can’t tolerate statin drugs. About 20 percent of statin users quit taking their medication due to side effects.
- Patients with complex lipid issues, such as low levels of heart-protective HDL (good) cholesterol and high triglycerides (a type of blood fat).
- People with inherited cholesterol disorders, such as elevated levels of lipoprotein (a), a type of cholesterol that triples heart attack risk and does not respond to statins. Taking niacin can reduce lipoprotein (a) levels by up to 40 percent, according to the European Atherosclerosis Society.
- Patients whose cholesterol problems aren’t responding to statins. Several studies show that statins plus niacin is more effective than statins alone.
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Side Effects of Niacin
In doses typically used to control cholesterol the vitamin can have an annoying side effect known as “the niacin flush,” a temporary and sometimes itchy or tingling redness of the skin that lasts about 30 to 60 minutes.
“Doctors know that if they advise niacin, they get calls from patients complaining about flushing, particularly at first,” says Dr. Bale. “However, this problem is harmless and can often be avoided by starting with a low dose that’s gradually increased.” Patients who experience flushing initially will typically find that the problem disappears or greatly diminishes over time.
While “non-flush” and extended-release forms of niacin are available, they appear to be less effective or may even have dangerous side effects, Dr. Bale adds. “There are two pathways through which the body can metabolize niacin, and the one that doesn’t cause flushing is more likely to harm the liver.”
Dr. Bale advises avoiding non-flush or extended-release formulations. In addition, niacin should only be used under the supervision of a healthcare provider, after a full discussion of the potential risks and benefits.
Like statins, niacin can cause muscle problems in some patients. It can also spark flare-ups in people with gout, and may contribute to GI bleeding in patients with ulcers, cautions Dr. Bale. “Any cholesterol treatment can cause side effects, but compared to statins, niacin is relatively safe.”
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A Controversial Niacin Study
In March, results of a highly publicized study of Tredaptive, an experimental drug containing extended-release niacin plus an anti-flushing drug called laropiprant, were interpreted by the media as showing that niacin may have dangerous side effects.
In the study, 25,673 patients who were already being treated with statins were randomly divided into 2 groups. One group took a statin drug plus Tredaptive and the other group received the same dose of statin along with a placebo.
Patients taking Treadaptive had higher rates of bleeding (2.5 percent vs. 1.9 percent) and infections (8 percent vs. 6.6 percent), as well as higher rates of new onset diabetes (9.1 percent vs. 7.3 percent). Nor did the patients on the experimental drug have lower rates of heart attack or stroke.
The study was halted prematurely, after four years, due to these problems and the maker of the experimental drug, Merck, announced that it wouldn’t be seeking FDA approval.
While media reports blamed these problems on niacin, Dr. Bale and other experts point out these adverse effects haven’t been seen in numerous previous studies of the vitamin on its own, so the anti-flushing drug is the likely culprit.
“Niacin is being thrown under the bus when it’s an inexpensive, effective treatment that’s been used very safely for decades,” says Dr. Bale. “What this study is telling us is that this particular no-flush combination drug doesn’t work and can have significant side effects.”
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