Both compounds have real biology behind them. NAD+ is central to cellular energy metabolism and glutathione is an important antioxidant. Interesting biology is not the same as demonstrated clinical benefit, and the leap from mechanism to 'this will extend your healthspan' has not been made by the evidence.
These are typically administered as compounded injectable preparations. FDA has reminded compounders that ingredients used in sterile compounding must be suitable for that purpose, which reflects real quality problems in this space. An injectable product carries infection and contamination risk that an oral supplement does not.
My position is not that these should be dismissed permanently. It is that they should be described accurately today: unproven for longevity, not FDA-approved for that use, and worth watching rather than selling.
Risks and limitations
- Human evidence for broad anti-aging or longevity benefit is limited.
- Compounded injectables are not FDA-approved and are not pre-market reviewed for quality.
- Sterile compounding quality problems have prompted FDA warnings.
- Infusion and injection reactions and infection risk are real considerations.
- Cost is often substantial relative to demonstrated benefit.