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As a doctor today I prescribe Niacin (Vitamin B3 ) rich foods to eradicate Pellagra.

Prevent the 4 Ds - Dermatitis ; Diarrhea ;Dementia and Death.

Dr Sampurna Roy MD          


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I only eat corn and maize, both my hands, forearms and neck are itching and burning, I have got severe diarrhea and I can't remember anything. What is wrong with me?



Pellagra is a systemic non-communicable disorder of poverty, caused by deficiency of niacin. 

It is still endemic in certain part of Asia and Africa where people mostly consume maize or sorghum (jowar) as staple food.

Niacin refers to two chemically distinct compounds: Nicotinic acid and Niacinamide (nicotinamide).

These biologically active components are derived from dietary niacin or are biosynthesized from available tryptophan.

Niacin plays a major role in the formation of nicotinamide adenine dinucleotide (NAD) and its phosphate (NADP), compounds important in intermediary metabolism and a wide variety of oxidation-reduction reactions. 

Chemistry and Physiology:

Niacin or nicotinic acid is prepared by oxidation of the alkaloid nicotine. It is Beta-pyridine carboxylic acid and is active only in the amide form.

Niacin is an essential molecular constituent of diphosphopyridine nucleotide and triphosphopyrinine nucleotide, which act as cofactors for several dehydrogenases.

Studies have shown niacin may be synthesized from dietary tryptophan. Pyridoxin aids in this process.

Source of Niacin in food:


1) Meat    2)Milk    3) Fish   4) Egg    5)Cheese



Animal protein, as found in meat, milk, butter, cheese, eggs, is rich in tryptophan. These are all good source of endogenously synthesized niacin. Niacin is available in many types of grain.

Although different views exist, regarding the etiology of Pellagra, there is general agreement that the major factor is deficiency of certain members of the B group of vitamins, particularly Niacin.

Some investigators believe that niacin deficiency should be regarded as the cause of pellagra,  despite the fact that most affected individuals show evidence of multiple dietary deficiencies.

It is seen principally in patients who have been weakened by other diseases and in malnourished alcoholics.

Those who do not eat sufficient protein may suffer a deficiency of tryptophan, which in combination with a lack of exogenous niacin may result in mild pellagra.

Malabsorption of tryptophan, as in Hartnup disease, or excessive utilization of tryptophan for the synthesis of serotonin in the carcinoid syndrome, may also lead to mild symptoms of pellagra.

Pellagra is particularly prevalent in areas where maize is the staple food  because the niacin in maize is chemically bound and thus poorly available. Maize is also a poor source of tryptophan.

Deficiencies of pyridoxine and riboflavin increase the requirement for dietary niacin because both of these cofactors are required for the biosynthesis of niacin from tryptophan.

Diphosphopyridine nucleotide and triphosphopyridine nucleotide, which have an abnormally low values in the blood and urine of persons with pellagra, rise to normal levels or higher when niacin is administered.

The pathologic changes of uncomplicated niacin deficiency have not been described in either humans or experimental animals.

Lesions that heal on administration of niacin are assumed to have been caused largely by lack of that compound. Pellagra is apparently a nutritional disease of the "conditioned" type.

Conditioning factors include exposure to sunlight, alcoholism, organic diseases, and infectious diseases.

The patient may have eating disorder like anorexia nervosa.

Other factors, such as mycotoxins, excessive dietary leucine intake , estrogens and progestogens,  and various medications, might also lead to the development of pellagra.

Qualitative deficiency in the aminoacid composition of the protein supply is probably a conditioning factor in pellagra.

The relationship of a cornmeal diet to pellagra is probably explainable on the basis of the fact that cornmeal is deficient in tryptophan, which is a precursor of nicotinic acid. There is also some evidence that cornmeal may contain an antagonist of nicotinic acid.

About 50% of persons with pellagra show achlorhydria.

Macrocytic anaemia which is not uncommon, is probably the result of concomitant folic acid deficiency.

History of Pellagra:

Pellagra is derived from the word pelle agra, Italian for rough skin.

It was first used by Francesco Frappoli who called it vulgo pelagrain in 1771, due to its dermatologic manifestations.

In the 18th century there was an epidemic in the poverty-stricken Spanish countryside and Gaspar Casal described the disease in 1972.

He noted that the patients with pellagra were all poor and malnourished.

They mainly depended on maize and rarely ate fresh meat.

Pellagra epidemic was reported in countries where maize is the staple food.  

Pellagra did not appear in the United States until the turn of the 20th century.

It then ravaged the Southern United States and was not eliminated until the 1940s.

Joseph Goldberger (1874-1929) played a key role to establish the nutritional basis for pellagra.

Goldberger conducted a series of studies on humans, together with experimental studies on animal model of the condition (black tongue in dogs). 

He was able to prevent and induce pellagra by appropriate dietary changes.


Conrad Arnold Elvehjem identified the "anti-black tongue factor" in liver extracts. According to him "Factor W"  an unidentified growth factor in liver extracts, was required for growth in addition to the known B vitamins.

Absence of the liver extract from a deficient diet resulted in black tongue in dogs as well as severe weight loss and poor health.

Elvehjem and his colleagues isolated the vital factor from liver extracts, and determined that the structure was nicotinic acid.

They also showed that pure nicotinic acid, as well as nicotinic acid amide, would completely substitute for the liver extract.


Pellagra is characterized by the three Ds of niacin deficiency :dermatitis , diarrhea, and dementia. Severe long-standing pellagra adds another D - death.

The skin changes are characteristic and pathognomonic.

Skin areas exposed  to light, such as the face and the hands, and those subjected to pressure, such as the knees and the elbows, exhibit a rough, hyperpigmented, scaly dermatitis.

The lesion has a brown-red coloration, with a sharply demarcated erythematous border, affecting both hands and lower forearms.

The skin lesion around the neck is known as "casal's necklace".

Macroscopically, the lesions are discrete and show areas of pigmentation and / or depigmentation.

Microscopically, there is hyperkeratosis, parakeratosis, epidermal atrophy, vascularization, and a mild superficial infiltrate of lymphocytes.

Vesicles if present are either subepidermal due to edema in the papillary dermis or intraepidermal due to degenerative changes in the epidermis.

Mild keratotic follicular plugging is noted.

In the chronic cases there is subcutaneous fibrosis and scarring and the amount of melanin in the basal layer is increased.

Similar lesions are found in the mucous membranes of the mouth and vagina.

In the mouth, inflammation and edema lead to large, red tongue, which in the chronic stage is fissured and is similar to raw meat.




   Diarrhea          Dementia        

Anorexia and malabsorbative diarrhea lead to a state of malnutrition and cachexia. 

A chronic, watery diarrhea is a typical feature of the disease but occasionally can be bloody and mucoid.

This is probably caused by mucosal atrophy and ulceration in the entire gastrointestinal tract, particularly in the colon.

Brain and spinal cord is affected in some patients.  These patients suffer from dementia and in some cases psychosis.

This is characterized by degeneration of ganglion cells in the brain cortex.

Like other deficiencies of the B vitamins, clinical niacin deficiency, pellagra, is rarely seen developed countries except in chronic alcoholics or rarely in those suffering from anorexia nervosa.


- Pellagra is a preventable disease and can be completely eradicated by improving the working conditions and wages of the poor agricultural and industrial workers.

- Dependence on maize as staple food should be discouraged. The vulnerable groups should be encouraged to eat meat, egg, fish and milk.

- Niacin tablets should be distributed to refugees and displaced people living in camps.

- Disease prevention education is necessary to teach people what type of food can prevent this condition.


Visit: Pathology of Vitamin A deficiency: Importance of Vitamin A in our daily diet

Visit: As a doctor today I prescribe Thiamine  (Vitamin B1) rich foods :Prevent Beriberi,Wernicke’s Encephalopathy, and Korsakoff’s Psychosis.

Visit:  As a doctor today I prescribe  Riboflavin  (Vitamin B2) rich foods to prevent mucocutaneous and ocular lesions

Visit: Eat Citrus Fruits everyday and keep Scurvy away - Pathology of Vitamin C Deficiency

Visit: As a doctor today I prescribe Vitamin K to prevent hemorrhage -The most important health problem of Vitamin K deficiency is Hemorrhagic Disease of the Newborn

Visit: As a doctor today I prescribe nutritious food for every hungry child  


Further reading:

A nutritional disease of childhood associated with a maize diet and pellagra

Starvation in the modern world.

The changing nutrition scenario.

Rapid resolution of delusional parasitosis in pellagra with niacin augmentation therapy.


Copper as an essential nutrient and nicotinic acid as the anti-black tongue (pellagra) factor: the work of Conrad Arnold Elvehjem.

[Two cases of pellagra. The 4D disease--forgotten but fatal].

Pellagra: a non-communicable disease of poverty.

Black urine due to urobilinogen in a patient with alcoholic pellagra.


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Dr  Sampurna Roy  MD

Consultant Histopathologist (Kolkata - India)






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