Causes of Pellagra disease (niacin deficiency)

› › Causes of pellagra disease

Causes of pellagra disease are or malabsorption of niacin (vitamin B3), and/or tryptophan (an essential amino acid). Depending on the formative factors pellagra may be primary or secondary.

Primary pellagra

Primary pellagra is the acute nutritional deficiency of niacin and/or tryptophan in the diet in freely available form.
Vitamin B3 (niacin, nicotinamide or nicotinic acid) deficiency causes pellagra disease

The deficit of vitamin B3 deranges all cellular functions and all biochemical mechanisms of the body systems go haywire and leads to the resultant debilitating symptoms. These causes of the disease are primary. Poor people are generally under nourished and their food may not include vitamin B3 and protein rich foods like organ meat, poultry, egg, milk, yeast etc..

This borderline deficiency leads to pellagra in them when there is a slight slide in their health. Populations, who depend mainly on maize as staple food tend to develop pellagra.
Maize food has niacin in biologically unavailable forms and causes pellagra disease.

Earlier populations boiled maize with lime before eating and it is found that this process makes niacin biologically available. People in low income groups, prisoners, people affected by famine and refugees are in the risk group. These people are to be monitored for symptoms of deficit and are to be helped with supplementation of vitamins.

Tryptophan (an essential amino acid) deficiency causes pellagra

Human body can produce vitamin B3 from the amino acid tryptophan.
Tryptophan is one of the amino acids which human body cannot synthesize and hence it is called as an essential amino acid. It has to be sourced only from food. The deficiency of tryptophan in diet causes pellagra disease.

Food of animal sources has sufficient levels of tryptophan.
In the food of plant origin tryptophan is available in nuts especially groundnuts and also in various beans.
Vegan food habit causes this malady. Vegans who do not include beans and nuts in their food are in the risk group.

Secondary pellagra disease causes
In a number of situations vitamin B3 may be present in available form and in sufficient quantities in the food. However extraneous factors lead to pellagra.
The presence of other diseases, assimilation disorders, utilization disorders and altered biosynthesis processes in the body may give rise to pellagra symptoms.

Leucine (an essential amino acid) can precipitate pellagra if present in high concentrations in the diet
People who frequently eat millet (sorghum or jowar) and whose staple food is millet are found to be affected by pellagra disease.
Millet contains both niacin and tryptophan. The causes of pellagra in millet eating populations are found to be the excessive leucine availability in millet and its interference in tryptophan metabolism and in the subsequent synthesis of niacin.

Chronic diarrhea causes pellagra

Chronic diarrhea, if not diagnosed and treated may lead to pellagra. As the individual's digestion and absorption mechanism gets affected in chronic diarrhea nutritional deficiency and dehydration sets in. This is not only the precipitating factor for pellagra but also many deficiency complications.

Elderly people are prone to develop pellagra
Elderly people's digestive system slowly gets impaired and the digestion and assimilation process slows down. Their condition is to be monitored closely and niacin and other vitamin supplements are to given. They are in the risk group of developing vitamin B3 deficiency.

Impaired digestion and gastrointestinal disorders causes pellagra

Persons with impaired digestive systems, celiac disease and tropical sprue develop nutritional deficiencies.They are prone to get deficit of vitamin B3.

Chronic alcoholism causes pellagra disease
Alcoholics due to their careless and erratic food habits, may not eat . The absorption and utilization of the niacin also gets affected in the alcoholics and they are prone to develop vitamin B3 deficiency.

Anorexia nervosa and pellagra
Anorexia nervosa, is a mental illness in which the patient suffers from low body weight. He evaluates himself to be overweight and starves himself with an obsessive fear of putting on weight.

In this mental disorder apart from starving, the patient may also exercise excessively and follow weight control measures. This naturally leads to nicotinic acid deficiency. Vit. B3 deficit leads to production of hunger suppressing endorphins and lack of appetite. The patient may develop skin and early psychiatric symptoms.

Carcinoid syndrome and pellagra

Carcinoid tumors are malignant tumors occurring on the intestinal wall and lungs. In these patients tryptophan is excessively converted into serotonin. This altered protein metabolism results in negligible niacin synthesis and causes this disease.

Hartup disease and pellagra
Hartups disease is a genetic autosomal disease caused by recessive trait. This impairs absorption of tryptophan in the intestines as well as kidneys. Very little amounts of tryptophan is absorbed in the intestines and excess of tryptophan is lost in the excretion. With this, there is no conversion of tryptophan into niacin and hence its deficiency disease.

Certain drugs and medications causes pellagra
The production of niacin from tryptophan depends on a co enzyme which is derived from vitamin B6. Isoniazid (used in the treatment of tuberculosis) and 3-mercaptopurine (used in the treatment of leukemia interfere with the metabolism of vitamin B6 and causes nicotinamide deficit. Some medications like chloramphenicol, hydantoins, phenobarbital, pyrazinamide and 5-fluorouracil have been found to become causes of nicotinamide deficiency disease.

Certain diseases and health conditions causes nicotinamide deficiency

Patients with liver cirrhosis, chronic ulcerative colitis, prolonged febrile illness, diabetes mellitus, AIDS, patients on intravenous fluids and patients on maintenance haemodialysis are prone to develop it. Liver cirrhosis, if untreated causes pellagra.
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Niacin deficiency causes pellagra disease.

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