Vitamin B3, also called niacin and nicotinic acid, is a water-soluble B vitamin. As with the rest of the B-vitamin family, niacin is involved in many aspects of energy metabolism and nervous system function. It plays a role in over 200 enzyme systems that release energy from carbohydrates and fats, metabolize proteins, make certain hormones, and assist in the formation of red blood cells, and perform many other functions. Niacin is thought to lower cholesterol and triglycerides; prevent and treat diabetes (as niacinamide); improve circulation (as inositol hexaniacinate); and relieve arthritis (as niacinamide).
A frank niacin deficiency causes pellagra, a condition that affects the skin and GI tract (diarrhea, nausea, vomiting and swollen tongue) and nervous system, (headache, depression, impaired memory, hallucinations and dementia). Niacinamide (nicotinamide) is the biologically active form of niacin. It is the preferred form of supplementation because it lacks the flushing effects of niacin. However, the flushing action may be necessary for its action of lowering cholesterol.
In the mid-1950s, research showed that that high doses of niacin (as nicotinic acid) could lower cholesterol levels by a still-unknown mechanism. The other form of niacin (nicotinamide or niacinamide) does not provide a cholesterol-lowering effect, but it may help prevent the development of childhood diabetes (Type I) in high-risk children. Cholesterol and triglyceride levels, heart attacks and strokes are all significantly reduced with niacin therapy (sometimes used alone and sometimes used along with other drug therapy). Overall, the beneficial use of niacin (nicotinic acid, but not niacinamide) to prevent or treat elevated blood lipids and reduce cardiovascular disease risk is well documented. Nicotinic acid consistently lowers total and LDL (“bad”) cholesterol (by about 15-20%) and triglycerides (by 10-25%), while increasing levels of HDL (“good”) cholesterol (by 15-25%). Unfortunately, the amount of niacin needed to lower cholesterol levels also tends to result in “niacin intolerance” in 15-40% of people who try it and the unpleasant side effect of “skin-flushing” (similar to hot flashes).
Dietary Sources: Rich dietary sources of niacin include many high-protein foods such as meat, chicken, tuna and other fatty fish, peanuts, pork and milk.
Dosage: The RDA for niacin is only 13-18 mg. The “cholesterol-lowering” dose of niacin (as nicotinic acid) is typically in the range of 250-2000mg/day. Dosing is usually started at the low-end (250mg/day) with increasing doses of 250mg each week or two until blood lipid levels start to normalize (or side effects develop).
Side Effects: In the high doses used for controlling cholesterol levels (anything above 100mg/day), nicotinic acid can cause skin flushing and itching of the skin as well as headaches and hypotension (lightheadedness and low blood pressure). The slow-release versions of niacin supplements for controlling blood lipids have the potential for causing liver damage (even at “lower” doses of 500mg/day) – so blood tests to monitor for liver damage are recommended and slow-release, high-dose niacin supplementation should only be undertaken on the advice and guidance by a physician.
The following citations present evidence of ongoing research on niacin for dyslipidemia and migraine and experimental investigation in cancer, lung disease, and skin disease. Earlier research with nicotinamide for the treatment of schizophrenia and mental disorders showed evidence of great therapeutic value. However, there is very little current research using in this important non-toxic modality. There is some research in “nicotinic systems in central nervous systems disease.”
1. Dyslipidemia, alone or in combination with statin drugs – hundreds of studies are evidenced in the literature.
3. Skin diseases
4. Oral niacin prevents photocarcinogenesis and photoimmunosuppression in mice.
5. Niacin attenuates acute lung injury induced by lipopolysaccharide in the hamster.
6. Early onset juvenile diabetes mellitus controlled with nicotinic acid therapy.
7. Nicotinamide may extend remission phase in insulin-dependent diabetes.
8. Attenuation of amiodarone-induced lung fibrosis and phospholipidosis in hamsters by taurine and/or niacin treatment.
9. Improved skin flap survival with nicotinic acid and nicotinamide in rats.
10. Effects of nicotinate ethyl ester treatment on gingival blood circulation of experimental gingivitis in monkeys.
11. Nicotinic acid in the treatment of chronic circulatory failure in patients with ischemic heart disease.
12. Nicotinamide is a potent inhibitor of proinflammatory cytokines.
13. Nicotinic treatment for degenerative neuropsychiatric disorders such as Alzheimer's disease and Parkinson's disease.
14. Nicotinamide in the treatment of schizophrenia.
Vitamin B3 Citations (372)