Why does severe Vitamin B3 (Niacin) deficiency primarily disrupt energy production in the citric acid cycle (Krebs cycle) pathway?

💡 Explanation

Niacin is a precursor to NAD+, a critical coenzyme for multiple dehydrogenases in the citric acid cycle. Reduced NAD+ impairs the cycle's function because these enzymes cannot proceed; therefore energy production via oxidative phosphorylation diminishes, rather than impacting fat transport or protein folding directly.

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