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How Vitamin B3 Works

Benefits of Vitamin B3
Vitamin B3 is available in three forms: nicotinic acid (also called nicotinate) and niacinamide (also called nicotinamide), both found in food and supplements; and inositol hexaniacinate, a form available only in supplements. Nicotinic acid and inositol hexaniacinate are both useful in reducing blood cholesterol levels. Niacinamide is helpful for some people with insulin-dependent diabetes and perhaps for arthritis sufferers.

Large doses of nicotinic acid -- 100 mg to 1,000 mg (1 g) daily -- are effective in lowering blood levels of triglycerides and the "bad" low-density lipoprotein (LDL) cholesterol, while increasing blood levels of the "good" high-density lipoprotein (HDL) cholesterol. This makes niacin an important tool in preventing or reversing heart disease. Niacin raises HDL cholesterol levels significantly more than the commonly used drug lovastatin. Although lovastatin lowers LDL cholesterol levels more than niacin does, the niacin also lowers blood levels of another lipid factor called Lp(a); researchers believe that elevated Lp(a) levels are an additional risk for cardiovascular disease.

When oat bran is added to the niacin regime, most people get even more impressive results. Kidney transplant patients, who often have high cholesterol levels, also see dramatic benefits from taking niacin. But niacin (as nicotinic acid) in doses higher than 500 mg daily can cause severe side effects, including liver damage, diabetes, gastritis, and an elevation in blood levels of uric acid (which can cause gout). So researchers and nutrition experts developed inositol hexaniacinate. Inositol hexaniacinate acts like niacin to lower cholesterol but without the severe side effects. People are able to supplement daily with doses up to 3000 mg (3 g) without risk of liver or stomach inflammation, nor does the supplement increase the risk of diabetes or gout.

Niacin is used to treat many ailments, including insulin-dependent diabetes.
©2007 Publications International, Ltd.
Niacin is used to treat many
ailments, including high

Insulin-dependent diabetes usually starts before the age of 20. Experts currently believe that diabetes can sometimes be caused as a result of an autoimmune response. The body attacks the insulin-making cells of its own pancreas, destroying them and robbing the body of insulin production. Sometimes prednisone is used to suppress the immune system and stop or slow down this process. Prednisone is a steroid drug and has many unwanted side effects, including elevating blood glucose levels. Researchers report that niacin, in the niacinamide form, may be even more effective than prednisone and much safer. Niacin blocks certain immune factors from destroying the crucial insulin-releasing cells. It also improves insulin production and sensitivity.

Numerous clinical studies show great promise for niacinamide. When given early during the onset of diabetes, it seems to help restore the insulin-producing cells. Patients go longer without needing insulin, use less insulin when it is needed, and have better blood glucose control. Other studies combined niacinamide with various immunosuppressive drugs, but results were not as good as with niacin alone. Since niacin can interfere with glucose tolerance, people with diabetes should not self-medicate. Work with a nutritionally trained medical doctor or registered dietician to be on the safe side.

Niacinamide may also help arthritis patients, particularly those with osteoarthritis, the most common form of this disease. Hundreds of patients report improvement after taking large doses -- up to 200 mg daily.

Some headache specialists prescribe Vitamin B3 in daily doses of 150 mg to help treat migraines, in the hopes that the dilating effects of niacin will help stabilize the overdilating-constricting cycle of cerebral blood vessels.

In the past, it was thought that Vitamin B3 might be beneficial for schizophrenia. Treatment results were so inconsistent, however, that niacin therapy is no longer attempted except in therapeutic trials while patients are in the hospital or other long-term care facility.

The best sources of Vitamin B3 are foods with a high protein content, such as meat, eggs, and peanuts. Go to the next page to learn more about foods that are rich in niacin.

Niacin isn't the only nutrient you need to maintain good health. Check out these links to learn more about vitamins that need to be part of your diet.
  • Vitamin A, or retinol, plays a vital role in vision. Learn more in How Vitamin A Works.
  • A vitamin B1, or thiamin, deficiency results in the disease beriberi. Learn more in How Vitamin B1 Works.
  • In How Vitamin B2 Works, read about how B2, or riboflavin, works in concert with its B-complex relatives to metabolize carbohydrates, fats, and proteins.
  • In How Vitamin E Works, learn about this important antioxidant with far-reaching health benefits.
  • Vitamin K is important in allowing your blood to clot properly. Learn more in How Vitamin K Works.

  • To learn about the many vitamins in our diet, how much you should be eating, and where to find them, go to our general Vitamins page.
  • To find the best prices on B vitamin supplements, click here.
This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.