FoundMyFitness × Dr Charles Brenner — what NAD actually does

Why this episode matters

NAD is the single most co-searched compound alongside "peptide therapy" — up 601% year-on-year. Every longevity clinic in the UK and US now bundles NAD drips with peptide stacks. Almost none of the marketing accurately represents what NAD actually is or what the evidence supports.

This episode is the correction.

Dr Charles Brenner discovered nicotinamide riboside (NR) as an NAD precursor and has spent a career on NAD metabolism. He is, by consensus, the most qualified living scientist on NAD biology. Rhonda Patrick's interview runs without commercial softening.

The summary tweet that put this episode on our radar: @jakeglmn — Apr 21 2026 ↗ (365k views). The frame: "Everyone from Joe Rogan to the Kardashians swears by NAD for anti-aging and recovery. Rhonda Patrick interviewed the scientist who discovered the molecule behind it."

Key positions Brenner defends in the episode

We will not reproduce large quoted passages — listen to the episode for those. Summarising his positions so you can evaluate whether it's worth your time:

1. NAD is not a peptide, and framing it as one is wrong. It is a nucleotide coenzyme central to mitochondrial energy metabolism and sirtuin activity. Pepwizard covers it on the NAD+ page because longevity clinics bundle it with peptide stacks, not because it is a peptide.
2. Oral precursors (NR, NMN) raise NAD levels slowly. This is the evidence-supported route. The total-body NAD pool restoration is modest per dose but compounds over weeks.
3. IV NAD+ drips deliver acute effects but the evidence base is thinner than clinic marketing implies. Brenner is explicit that clinical outcomes from IV NAD+ are mostly uncontrolled or anecdotal.
4. NAD supplementation is not "anti-aging" in the regenerate-your-cells sense clinic copy often suggests. It is best understood as restoring an age-declining coenzyme pool. Whether that translates to measurable healthspan outcomes in otherwise-healthy adults is still an open question.
5. The risks are real but dose-dependent. Very high doses shift methylation and can produce atypical effects that lower-dose precursor regimens do not.

What this means if you're buying NAD

Three practical takeaways:

• If you are buying oral precursors, NR and NMN have the strongest mechanistic support. Dosing typically 250–500 mg daily. See the NAD+ prices page.
• If you are getting IV drips, understand you are paying for an acute effect with thin controlled evidence, not a pharmacologically established treatment. That doesn't mean it doesn't work — it means your belief about whether it works should be calibrated.
• If a clinic tells you NAD reverses aging, they are selling past what the science currently supports. Brenner is clear on this.

Where to go next

• NAD+ prices and protocols
• Longevity stack
• Cheapest NAD+ globally
• FoundMyFitness (Rhonda Patrick's site) →

Sources: @jakeglmn summary ↗ · FoundMyFitness.