A) What is pellagra? What are the concequences of ingesting too much niacin?

Vitamin B3 also known as niacin helps maintain the normal function of the skin, nerves and digestive system. The disease pellagra results from a severe niacin deficiency. Niacin has the following formula: C6H5O2. Often tablets contain vitamin B3 in the form of niacinamide C6H6N2O which is easier to absorb.