The role of niacin is inextricably linked to pellegra, where a deficiency of this water-soluble B3 vitamin brings about a disease that is potentially fatal. Since niacin was not officially recognized as a vitamin until 1937, not much attention was given to it pertaining to pellegra, but once they discovered it could cure black tongue (canine version of pellegra) in a dog, by 1941, scientists and manufacturers saw fit to start fortifying cereals, breads, and pasta with niacin. Since then, the plague of pellegra has become almost non-existent in America.
Niacin is important in the body as a component of two co-enzymes that do the work of utilizing proteins/carbohydrates/fats, all macro-nutrients that release energy to the body, as well as being involved in the synthesis of fatty acids and steroids. As the amino acid tryptophan can also be converted to one form of niacin (nicotinic acid), eating foods high in tryptophan can compensate for a lack of niacin as it provides approximately 2/3 of the recommended daily allowance (16 mg for men, 14 mg of niacin for women). By eating a diet that includes meat, green vegetables, yeast, most grains, nuts and legumes can dramatically help cure pellegra. Turkey and milk are also good sources of tryptophan.
Niacin is a vitamin that is readily absorbed by the stomach and small intestine, while the main storage organ for this important nutrient is the liver. However, with certain grains like corn or wheat, where niacin is bound to components in cereal products, makes it bio-unavailable for absorption. For that reason, many countries that use maize as a staple without first treating it with lime water are at risk for pellegra. Therefore, in modern day, manufacturers have seen fit to use lime water in the manufacturing process, when making tortillas for use in Mexico and Central America.
A marginal deficiency in niacin can cause a plethora of symptoms: from insomnia to weight/strength loss; digestive problems and abdominal pain; nervous system issues to mental affectations that include poor concentration, confusion, and forgetfulness.
When severe deficiency leads to pellegra, the main symptoms are dermatitis, diarrhea, and dementia. A lack of niacin attacks the skin, especially in parts of the body frequently exposed to the sun. A person often experiences a pigmented rash on skin; pellegra is the Italian term meaning raw skin. In turn, pellegra manifests in the digestive system by a person showing a bright red tongue, stomatitis, vomiting, and diarrhea. Stomatitis is a symptom that involves inflammation of the mucous lining of the mouth, tongue, lips, cheeks, etc.
Since pellegra also affects the mind, in the old days, people were often placed in mental institutions, as well as hospitals when ravaged by this disease. Symptoms include headache, fatigue, depression, apathy, and loss of memory, all neurological signs of pellegra. When symptoms of pellegra are left untreated, it can be fatal.
Since other B vitamins are needed for the production of niacin through tryptophan, a deficiency of B6 and riboflavin can also lead to pellegra. Furthermore, people with Hartnup’s Disease, a genetic disorder that affects absorption of tryptophan can contribute to development of pellegra. Even though pellegra is rarely seen now in industrialized countries, other parts of the world such as China, India, and Africa are still afflicted with niacin deficiency. About the only time one sees pellegra in America is when a person has chronic alcoholism.
Pellegra can be a dangerous disease, but the good news is, it can be remedied by getting enough tryptophan through diet or taking niacin supplements to prevent a deficiency. By eating foods such as turkey, meats, green vegetables, nuts, and legumes, a person can help prevent pellegra.