Nicotinamide Riboside Increases NAD+ Through Two Distinct Pathways: Preclinical Findings

Synopsis

Nicotinamide riboside (NR), a precursor to NAD+, can increase NAD+ levels in the body through two mechanisms. When taken orally, NR is first directly absorbed and converted to NAD+ via the NR salvage pathway. Later, NR is broken down into nicotinamide (NAM) by the enzyme BST1 and further processed by gut bacteria into nicotinic acid, which then contributes to NAD+ production via the Preiss–Handler pathway. Additionally, BST1 can switch NR and nicotinic acid riboside (NAR) back and forth, connecting these two NAD+ pathways. This dual role of BST1 helps explain how oral NR supplementation effectively boosts NAD+ in the body.

Journal

Nature Communications