system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Niacin deficiency cause
assistant
The correct answer is  Niacin 

This vitamin differs from the other vitamins of the B-complex group in that an essential amino acids tryptophan serves as its precursor.
Another characterstic of niacin is that it is not excreted in urine as such, but is metabolised to two major methylated derivatives.


N-methyl-nicotinamide
N-methyl pyridones


Niacin deficiency results in *Pellagra ’
Pellagra is identified by the presence of three 'D's → Diarrhea, Dementia, Dermatitis.