Vitamin B-3 is made up of niacin (nicotinic acid) and its amide, niacinamide, and can be found in many foods, including yeast, meat, fish, milk, eggs, green vegetables, and cereal grains. Dietary tryptophan is also converted to niacin in the body. Vitamin B-3 is often found in combination with other B vitamins including thiamine, riboflavin, pantothenic acid, pyridoxine, cyanocobalamin, and folic acid.

Evidence

These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Uses based on scientific evidence

High cholesterol (niacin)

Niacin is a well-accepted treatment for high cholesterol. Multiple studies show that niacin (not niacinamide) has significant benefits on levels of high-density cholesterol (HDL or "good cholesterol"), with better results than prescription drugs such as "statins" like atorvastatin (Lipitor®). There are also benefits on levels of low-density cholesterol (LDL or "bad cholesterol"), although these effects are less dramatic. Adding niacin to a second drug such as a statin may increase the effects on low-density lipoproteins.The use of niacin for the treatment of dyslipidemia associated with type 2 diabetes has been controversial because of the possibility of worsening glycemic control. However, a recent randomized controlled multicenter trial reports that of 148 patients, only 4 discontinued niacin because of inadequate glucose control. Doses of 1000-1500 mg per day (in a controlled release formulation) were reported as a potential treatment option for type 2 diabetics with dyslipidemia by these researchers. Patients should check with a physician and pharmacist before starting niacin.

Pellagra (niacin)

Niacin (vitamin B-3) and niacinamide are FDA approved for the treatment of niacin deficiency. Pellagra is a nutritional disease that develops due to insufficient dietary amounts of vitamin B-3 or the chemical it is made from, tryptophan. Symptoms of pellagra include skin disease, diarrhea, dementia and depression.

Atherosclerosis (niacin)

Niacin decreases blood levels of cholesterol and lipoprotein (a), which may reduce atherosclerosis ("hardening" of the arteries). However, niacin also can increase homocysteine levels, which may have the opposite effect. Overall, the scientific evidence supports the use of niacin in combination with other drugs (but not alone) to decrease cholesterol and slow the process of atherosclerosis. More research is needed in this area before a firm conclusion can be drawn.

Prevention of a second heart attack (niacin)

Niacin decreases levels of cholesterol, lipoprotein (a), and fibrinogen, which can reduce the risk of heart disease. However, niacin also increases homocysteine levels, which can increase this risk. Numerous studies have looked at the effects of niacin, alone and in combination with other drugs, on the prevention of heart disease and fatal heart attacks. Overall, this research suggests benefits of niacin, especially when combined with other cholesterol-lowering drugs.

Osteoarthritis (niacinamide)

Preliminary human studies suggest that niacinamide may be useful in the treatment of osteoarthritis. Further research is needed before a recommendation can be made.

Alzheimer's disease/ cognitive decline

Dementia can be caused by severe niacin insufficiency, but it is unknown whether variation in intake of niacin in the usual diet is linked to neurodegenerative decline. One study examined whether dietary intake of niacin was associated with incident Alzheimer's disease (AD) and cognitive decline in a large, prospective study. The authors conclude that dietary niacin may protect against AD and age related cognitive decline. Further research is needed to confirm these results.

Uses based on tradition or theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.

Acne, age-related macular degeneration, alcohol dependence, anti-aging, anxiety, arthritis, Bell's palsy, blood circulation improvement, blood vessel spasms, bone marrow damage from chemotherapy, cancer prevention, cataract prevention, central nervous system disorders, cholera diarrhea, chronic diarrhea, confusion, depression, diagnostic test for schizophrenia, digestion improvement, drug-induced hallucinations, ear ringing, edema, glucose intolerance, hearing loss, heart attack prevention, HIV prevention, high blood pressure, hypothyroidism (reduced thyroid function), insomnia, intermittent claudication (painful legs from clogged arteries), "ischemia-reperfusion injury" prevention, kava-related skin disorders, leprosy, liver disease, low blood sugar, memory loss, Meniere's syndrome, migraine headache, motion sickness, multiple sclerosis, non-ST-segment elevation acute coronary syndromes, orgasm improvement, painful menstruation, peripheral vascular disease, photosensitivity, pregnancy problems, premenstrual headache prevention, premenstrual syndrome, prostate cancer, psoriasis, psychosis, Raynaud's phenomenon, schizophrenia, scleroderma, sedative, seizure, skin disorders, smoking cessation, stomach ulcer, tardive dyskinesia, taste disturbances (diminished/distorted sense of taste), tuberculosis, tumor detection, vertigo.

Tags: Herbal Medicine, Vitamins

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