Why does a thiamine deficiency disrupt cellular energy production more severely than a deficiency in non-cofactor amino acids?

💡 Explanation

Thiamine, as thiamine pyrophosphate (TPP), is an essential cofactor for enzymes like pyruvate dehydrogenase. Therefore, thiamine deficiency directly impairs the citric acid cycle and ATP production because critical metabolic pathways are halted, rather than just slowed as with limiting amino acids.

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