The timeline for noticing benefits from NAD+ supplementation varies widely depending on the delivery method, dosage, and baseline health status. Clinical studies show that oral precursors like nicotinamide riboside can significantly elevate blood NAD+ levels within a few weeks, with users frequently reporting noticeable improvements in daily energy, mental clarity, and physical recovery after two to four weeks of consistent daily use. Intravenous infusions may offer immediate subjective energy boosts.