Human Nutrition 3(3+0)

Lesson 26 : Nicotinic Acid (Niacin)

Pellagra

The disease is also known as disease of the three D’s- dermatitis, diarrhoea and dementia (mental symptoms). Dermatitis or rough and painful skin is seen especially on areas exposed to the sun. In addition, glossitis and stomatitis are usually present. Glossitis and diarrhoea are the two outstanding symptoms. The glossitis and stomatitis vary from a mild redness, soreness and smoothness of the tongue and mouth to an extreme inflammation with fiery red mucosa, tongue ulceration and secondary infection of the tongue and buccal mucosa. Nausea and vomiting are seen in most cases.

The high leucine content of maize is one of the major factors contributing to the development of pellagra on maize based diets. The nutritional defects in maize giving rise to pellagra are:

• Low nicotinic acid content
• Low tryptophan and
• High leucine content of maize proteins.