NAD+ and Cellular Energy: The Longevity Basics

NAD+ (nicotinamide adenine dinucleotide) is a coenzyme present in every cell you have. It powers the reactions that convert food into usable energy and supports the enzymes involved in DNA repair.

Why NAD+ declines

NAD+ levels fall measurably with age, and that decline tracks with reduced mitochondrial efficiency, slower repair, and the fatigue many people describe in their forties and fifties. Chronic inflammation, poor sleep, and alcohol accelerate the drop.

What supplementation targets

Restoring NAD+ availability aims to support:

• Mitochondrial energy production
• Sirtuin activity involved in cellular repair
• Cognitive clarity and daytime energy
• Metabolic flexibility

Delivery matters

Oral precursors, nasal sprays, and injectable NAD+ differ substantially in bioavailability. Injectable and nasal routes bypass first-pass metabolism, which is why physicians often prefer them when a patient's primary complaint is fatigue.

Foundations first

Supplementation works best alongside the behaviors that preserve NAD+ in the first place: consistent sleep, zone-2 cardio, resistance training, limited alcohol, and time-restricted eating.

Getting started

A physician-guided longevity protocol starts with baseline labs and a review of your goals, then adjusts dose and route based on how you respond over the first 8–12 weeks.