Niacin (also known as vitamin B3 or nicotinic acid), is one of the water-soluble B-complex vitamins that provides a range of health benefits, including reducing your level of "bad" LDL cholesterol while raising your level of "good" HDL cholesterol. The body uses niacin, as it does the other B vitamins, to convert food into energy and maintain a healthy nervous system. Niacin also plays a key role in the metabolism of fats, including the synthesis of such fat-based hormones as androgens, estrogens, progestins and stress-related hormones.
The benefit of niacin to healthy brain function has been demonstrated by a study showing its effectiveness in helping protect against age-related cognitive decline and Alzheimer's disease. Researchers from the Centers for Disease Control and Prevention conducted a study on nearly four thousand elderly residents of a Chicago community. Over a period of almost six years, the residents' dietary data was collected and cognitive assessments were conducted. The results found a definite positive correlation between niacin intake and reduction in mental impairment.
A derivative of niacin, niacinamide, is often useful in the treatment of osteoarthritis and rheumatoid arthritis. Dr. William Kaufman has been studying the use of niacinamide in the treatment of arthritis since the 1950s and writes of its benefits, "It measurably improves joint mobility, muscle strength, decreases fatigability. It increases maximal muscle working capacity, reduces or completely eliminates arthritic joint pain."
As the body is unable to absorb more than 250 mg of niacinamide at a time, it is more effective to take smaller does more often (perhaps every one to three hours) than one large dose per day. It is estimated that nearly 70 percent of arthritis patients will experience increased joint mobility after four weeks of treatment.
Though niacin deficiency is uncommon, it tends to occur most often in populations that suffer from poverty, malnourishment or chronic alcoholism. This deficiency can lead to a disease called pellagra, in which the patient suffers from dermatitis, diarrhea and dementia. A severe lack of niacin can be deadly, if left untreated. Populations who use corn products (such as cornmeal) as the main staple of their diet often suffer from pellagra, as the niacin in corn is not easily absorbed by the body. Interestingly, adding limestone during cooking (often just by cooking food in high calcium content water) helps to make the vitamin bio-available, and Native Americans have incorporated ash from their cooking fires into their corn-based dishes for generations.
The recommended daily intake of niacin is 14-16 mg per day for adults, which can be easily achieved from eating a balanced diet. The food sources highest in niacin are yeast, meat, poultry, tuna, salmon, whole grain cereals, legumes and seeds. Other good sources are green leafy vegetables, coffee, tea and milk.