Niacin belongs to the family of B vitamins (B3), along with others such as cyanocobalamin, thiamine, riboflavin and folic acid. General health benefits of Vitamin B include supporting metabolism, function of immune and nervous system, cell growth and division. Niacin can be found in many food sources, ranging from legumes to a variety of meat products. It can also be synthesized by our liver from 60mg of tryptophan amino acid to yeild 1mg of niacin.
The only legume that is low in niacin content is maize. Dietary deficiency typically occurs in developing countries where mazie is the main staple food. As well, our bodies cannot store excess niacin for later uses as it is water-soluble and secreted through urine. Hence, continuous supply of niacin is needed to avoid deficiency. Manufacturing process called nixtamalization can increase the bioavailablily of niacin in maize products. Severe deficiency in niacin causes the disease pellagra. Symptons include digestive problems, inflamed skin, mental impairment, diarrhea, dementia, and anemia. Pellagra also leads to psychiatric symptoms such as irritability, poor concentration, anxiety, fatigue, restlessness, apathy and depression. If left untreated, it could lead to death. A genetic disorder resulting in the deficiency of niacin is called Hartnup’s disease. The livers and lungs of patients with Hartnup’s disease have a significantly lowered ability to break down and absorb dietary tryptophan.
Some pharmacology research has shown that niacin may be effective in reducing total cholesterol, triglyceride, very-low density lipoprotein (VLDL), and low-density lipoprotein (LDL), as well as increasing high-density liprotein (HDL), which are known as “good” cholesterols in our blood. In order for these effects to be observed, clinically prescribed doses of 1-2g are taken three times daily.
The recommended daily allowance of niacin is 2 ~ 12mg/day for children, 14mg/day for women, 16mg/day for men,and 18mg/day for pregnant or lactating women. A person should not exceed consumption of 35mg/day or side effects such as flushing may start to appear.
References:* (1) http://en.wikipedia.org/wiki/Niacin (2) http://www.nlm.nih.gov/medlineplus/ency/article/002409.htm
