Niacin (Vitamin B3)

The niacin or nicotinic acid form of vitamin B3 has been known to be an effective method for lowering blood cholesterol levels since the 1950s. In the 1970s, the famed Coronary Drug Project demonstrated that niacin was the only cholesterol-lowering agent to actually reduce overall mortality. Niacin typically lowers LDL cholesterol levels by 16 to 23 percent while raising HDL cholesterol levels by 20 to 33 percent. These effects, especially the effect on HDL, compare quite favorably to conventional cholesterol-lowering drugs.

Inositol hexaniacinate, a form of niacin that has been used in Europe for over thirty years, has been shown not only to lower cholesterol but also to improve blood flow in the treatment of Raynaud’s phenomenon (a painful response of the hands or feet to cold exposure, due to constriction of blood vessels supplying the hands) and intermittent claudication (a painful cramp in the calf produced when walking, a result of decreased oxygen supply to the calf muscle). Double-blind studies have verified the beneficial effects of this form of niacin in these peripheral vascular disorders.

Available Forms

Vitamin B3 is available as niacin (nicotinic acid or nicotinate); inositol hexaniacinate; and niacinamide. Niacin and inositol hexaniacinate are useful in lowering blood cholesterol levels, while niacinamide is useful in arthritis and early-onset type 1 diabetes.

Niacin is available as pure crystalline niacin and in sustained- or timed-release preparations. Because of the significant risk of liver toxicity, sustained-release niacin should not be used unless prescribed by a physician. Inositol hexaniacinate yields slightly better results than standard niacin but is much better tolerated in terms both of flushing and, more important, long-term side effects.

Cautions and Warnings

Because niacin can damage the liver, periodic checking (minimum every three months) for liver enzyme levels in the blood is indicated. Please tell your physician that you are taking niacin and wish to be monitored.

Because niacin can impair glucose tolerance, it should probably not be used in diabetics unless they are under close observation.

Niacin should not be used in patients with preexisting liver disease or elevation in liver enzymes, gout, or peptic ulcers.

Doses in excess of 50 mg of niacin typically produce a transient flushing of the skin. Other occasional side effects of niacin include gastric irritation, nausea, and liver damage. To get around the problem of skin flushing, drug and supplement manufactures have developed time-release products. However, while these preparations may effectively eliminate the problem of skin flushing, they are associated with greater liver dest4ruction and serious side effects. A better recommendation to eliminate the problem of skin flushing is to use inositol hexaniacinate. Both short- and long-term studies have shown it to be virtually free of side effects other than an occasional person experiencing mild gastric upset or mild flushing of the skin.

Drug Interactions

Niacin has been shown to potentiate the cholesterol-lowering effects of other lipid-lowering drugs, especially the statin drugs, such as atorvastatin (Lipitor), gemfibrozil (Lopid), lovastatin (Mevacor), pravastatin (Pravachol), and simvastatin (Zocor).

Because niacin can impair glucose tolerance, it may interfere with drugs used in the treatment of diabetes. If you are diabetic, consult a physician to discuss proper monitoring of blood sugar levels before taking niacin at therapeutic levels.

Aspirin and other nonsteroidal anti-inflammatory drugs can blunt the flushing effect of high-dosage niacin.

Usual Dosage

Niacin is generally recommended at a dosage of 20 to 50 mg for general health purposes and to prevent deficiency. When being used to lower cholesterol levels, the dosage recommendation for crystalline niacin is to start with a dose of 100 mg three times a day and carefully increase the dosage over a period of four to six weeks to the full therapeutic dose of 1.5 to 3 g daily in divided dosage or as a single dosage at night. If inositol hexaniacinate is being used to lower cholesterol or improve blood flow in Raynaud’s phenomenon or intermittent claudication, begin with 500 mg three times daily for two weeks and then increase to 1,000 mg three times daily. Either crystalline niacin or inositol hexaniacinate is best if taken with meals. Sustained-release niacin should not be used unless prescribed by a physician.

Osteoarthritis and rheumatoid arthritis

In the 1940s and 1950s, Doctors reported very good clinical results in the treatment of hundreds of patients with rheumatoid arthritis and osteoarthritis using high-dose niacinamide (900 to 4,000 mg per day in divided doses). Doctors documented improvements in joint function and range of motion, increased muscle strength and endurance, and reduction in the sedimentation rate. Most patients achieved noticeable benefits within one to three months of use, with peak benefits noted between one and three years of continuous use.

These clinical results were upheld in a more recent double-blind study in patients with osteoarthritis. Researchers found that niacinamide produced a 29 percent improvement in all symptoms and signs compared to a 10 percent worsening in the placebo group. Pain levels did not change, but hose on niacinamide reduced their use of pain-relieving drugs.