A patient presents with glossitis and dermatitis due to a dietary restriction. Which mechanism explains why tryptophan deficiency in the diet leads to these symptoms?

💡 Explanation

Niacin (vitamin B3) can be synthesized from tryptophan. Because tryptophan deficiency reduces niacin production, this leads to pellagra-like symptoms such as dermatitis and glossitis; therefore, insufficient niacin synthesis is the key mechanism, rather than calcium, iron, or ascorbate deficiencies.

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