A patient exhibits dermatitis, diarrhea, and dementia. Which mechanism explains why high doses of leucine can sometimes exacerbate these symptoms?

💡 Explanation

High doses of leucine can inhibit tryptophan conversion to niacin, exacerbating pellagra symptoms because tryptophan is a precursor to niacin (vitamin B3). Therefore, a leucine overload worsens the niacin deficiency, rather than addressing serotonin, iron, or folate imbalances.

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