Pellagra leucine excess

Pellagra is currently thought to be due to imbalance of dietary amino acids and deficiency of niacin. The common variety of maize is rich in leucine, which inhibits synthesis of nicotinic acid mononucleotide and causes deficiency of NAD+ and NADP+. A strain of maize known as opaque 2 contains less leucine and does not cause pellagra unless excess leucine is added to the diet. 

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