Try to survive on a corn-based diet, and you run the risk of getting pellagra, a disease caused by niacin deficiency. Corn lacks niacin. Years ago, people in the South who depended on corn grits as a diet staple suffered from this body-wide disease that leads to dermatitis, diarrhea, and depression. It can even lead to death, if deprivation continues long enough.
Today, nearly everyone gets sufficient niacin. Meat, poultry, and fish are rich in this B vitamin, and it’s also added to flour and other cereal products to help ensure that our needs are met. Pellagra, for the most part, is a thing of the past.
Like most of the other B vitamins, niacin assists enzymes, the catalysts that help spark chemical reactions. An all-around booster shot for enzymes, it helps many of them do their jobs properly.
Niacin is also a major player in the process of breaking down food into a form of energy that the cells in our bodies can either use or store for future use. Niacin-dependent enzymes help "package" this energy and then release it in an orderly fashion as it’s needed.
The niacin-dependent enzymes also play an important role in the body’s handling of fat and cholesterol and the production of many biochemicals, including some hormones.
Confusingly, niacin has several different chemical structures, which also have different names. One of the forms prescribed by doctors is nicotinic acid. A second form is called niacinamide—also known as nicotinamide. And there’s yet a third form—different from the other two—called inositol hexaniacinate.
Some forms are recommended for certain conditions but not for others. Niacinamide, for instance, is used to treat osteoarthritis and rheumatoid arthritis. Other forms may be selectively prescribed in large doses to treat high cholesterol and Raynaud’s disease, a circulatory problem that causes cold hands and feet.
Clobbering Cholesterol
Large doses of nicotinic acid and inositol hexaniacinate do a good job of lowering cholesterol, possibly by affecting liver function.
Niacin also raises "good" HDL cholesterol. In fact, it does this better than any drug on the market. Several studies also show that regular doses of niacin can reduce the risk of death from heart disease. It is thus considered a good treatment choice when someone needs more than diet to control cholesterol, says Martin Milner, N.D., a naturopathic doctor who teaches at the National College of Naturopathic Medicine in Portland and Bastyr University in Bothell, Washington.
This is one treatment, however, for which knowledgeable medical supervision is a top priority. In the large doses needed to lower cholesterol—1,500 to 3,000 milligrams a day—niacin can cause liver problems. In fact, problems can start with doses as low as 500 milligrams, although some effects might not show up for years.
SUPPLEMENTSNAPSHOT
| Niacin Supplement forms: Nicotinic acid, niacinamide (nicotinamide), and inositol hexaniacinate; also known as vitamin B3. May help: Niacin and inositol hexaniacinate may help high cholesterol and Raynaud’s disease; Niacinamide may help osteoarthritis, rheumatoid arthritis, and diabetes. Daily Value: 20 milligrams. Special instructions: Take with food to minimize side effects whenever you’re taking high doses. Who’s at risk for deficiency: Alcoholics and people taking isoniazid (Laniazid) for long periods of time. Good food sources: Meat, milk, eggs, fish, poultry, peanuts, and enriched breads and cereals. Coffee and tea also contain appreciable amounts. Cautions and possible side effects: Do not take more than 35 milligrams a day of any form without medical supervision; do not take more than 35 milligrams daily if you have a history of gout, liver damage, peptic ulcers, gallbladder disease, or heart rhythm disturbances. Taking niacin in addition to certain cholesterol-lowering drugs (“statin” drugs) increases risk of liver damage. High doses can cause drops in blood pressure and can raise blood sugar in people with diabetes. May cause flushing and allergic reactions. |
Anyone who is taking high doses must have regular blood tests to measure three essential liver enzymes, says Dr. Milner. You may find timed- release forms of niacin on your drugstore shelf, but immediate-release niacin is less likely to cause liver damage.
Dr. Milner uses inositol hexaniacinate (Niacinol) because studies show that it is also less likely than the timed-release form to cause liver damage. There’s also less chance of this form causing niacin flush, the characteristic reddening of the skin and itching that some people experience after taking niacin. Even though it’s readily available from naturopathic doctors and at some health food stores, however, it’s not something that you should try without regular monitoring, Dr. Milner says.
With inositol hexaniacinate, the doctor might start you on a dose of 1,500 milligrams. If you take regular niacin, your doctor will begin with a much lower dose and increase it gradually over a period of weeks to help minimize flushing, says Dr. Milner.
Helping Vessels and Joints
Niacin can help people with Raynaud’s disease for reasons that are related to the way it causes blood vessels to expand. For someone with Raynaud’s, the blood vessels in the hands essentially clamp down, cutting off a warming blood supply. When it’s severe, the hands literally turn white with cold.
Because niacin helps blood vessels expand, it seems to be just what the doctor ordered for Raynaud’s. Some doctors, usually naturopaths, do prescribe it for this condition. "Niacin’s ability to dilate the superficial blood vessels of the skin, mostly around the chest and face but also in the hands, helps to stop bouts of Raynaud’s," Dr. Milner says.
The rationale for using niacinamide for arthritis is based mostly on the work of William Kaufman, M.D., Ph.D., a doctor who pioneered nutritional therapy for people with the joint inflammation caused by this disease. Some naturopathic doctors recommend up to 500 milligrams twice a day. "This form acts differently in the body than niacin does," Dr. Milner says. "It’s thought to improve certain functions in the cells. It does seem to be safe at these amounts, though."
