In this episode of the NutritionFacts Podcast, Dr. Michael Greger explores NAD+ (nicotinamide adenine dinucleotide)—a molecule central to energy metabolism, DNA repair, and healthy aging. He reviews its history, scientific discoveries, and the hype around supplements, separating fact from fiction.

Key Points:

NAD+ is essential for life and deeply tied to healthy aging, but the hype around supplements often outpaces the science. For now, lifestyle strategies—nutrition, movement, and sleep—remain the safest way to protect your NAD+ and your healthspan.

• What is NAD+ and Why It Matters: NAD+ is a vital molecule found in every living cell, supporting over 500 enzymes and essential for extracting energy from food. Its link to sirtuins—proteins that guard healthspan—has made it a focus of modern aging research.
• Does NAD+ Really Decline with Age?: While supplement companies claim levels drop dramatically, research shows mixed results: some tissues show modest declines, others remain stable, and overall evidence for a universal decline is weak.
• Animal Evidence vs. Human Proof: In rodents, boosting NAD+ improves muscle, brain, heart, and immune health, even extending lifespan. But in humans, evidence is limited and inconsistent, with only rare cases (like certain genetic disorders) showing clear benefits.
• Supplements- Promise and Risks: Common NAD+ boosters include niacin (NA), niacinamide (NAM), nicotinamide riboside (NR), and NMN. While high-dose niacin can raise NAD+ levels, it comes with side effects such as flushing, liver issues, and even increased diabetes risk. Costly newer supplements often break down into the same basic precursors.