NAD+ IV therapy claims vs. what the research actually shows

What did @timothy.mountcastle actually say?

The core argument here is blunt: NAD injections are not FDA-approved, they come from compounding pharmacies with documented safety concerns, and you can skip the whole thing by just taking vitamin B3 orally. He also takes a side swing at B12 "skinny shots," calling them "garbage" and "false advertising." The plastic surgeon framing gives this some credibility on the regulatory side, though that credential matters less for the metabolic biochemistry he wades into.

His main claims boil down to three things: NAD injections have no FDA approval, oral B3 precursors can raise NAD levels endogenously, and take-home injectable NAD kits are dangerous. He's not entirely wrong, but he's also not telling the complete story.

Does the science back this up?

Partially, and it depends which claim you're checking. On the FDA status, he's correct. NAD+ for injection has no FDA-approved indication, and the FDA has issued alerts about compounded NAD+ products citing sterility concerns and adverse event reports. That part holds up.

The oral B3 argument is where things get messier. Nicotinamide riboside (NR) and nicotinamide mononucleotide (NMN) are NAD+ precursors that have shown measurable increases in blood NAD+ levels in human trials. Elhassan et al. (2019, Cell Reports) demonstrated that oral NR supplementation significantly raised whole-blood NAD+ in healthy older adults. Rajman et al. (2018, Cell Metabolism) reviewed the preclinical and early clinical evidence for NAD precursors broadly. So yes, oral routes work for raising NAD+. But "take some vitamin B3" oversimplifies the precursor landscape considerably. Plain niacin, NR, and NMN are not interchangeable, and the bioavailability differences are real.

What did they get wrong (or right)?

He got the regulatory picture right. NAD injections are compounded, not FDA-approved, and there are legitimate safety questions about sterility and preparation quality. Giving patients take-home injectable NAD kits is a legitimate concern worth raising loudly.

Where he stumbles is conflating all forms of vitamin B3 as equivalent NAD precursors. Saying "just take some vitamin B3" flattens a meaningful biochemical distinction. Nicotinic acid (classic niacin) and nicotinamide have different conversion efficiencies and side effect profiles compared to NR or NMN. The research behind NR and NMN is more specific than plain niacin supplementation for NAD+ repletion. Conze et al. (2019, Scientific Reports) showed NR's safety and pharmacokinetics in detail. The "endogiously" comment, likely meaning endogenously, is a slip but the underlying point about endogenous synthesis is real.

On the B12 "skinny shot" claim, he's largely correct. There is no robust clinical evidence that injectable B12 promotes weight loss in people who are not B12-deficient. That characterization as false advertising is fair.

What should you actually know?

The honest picture is that NAD+ biology is genuinely interesting and the compounded injection market is running well ahead of the evidence. That doesn't mean injections are useless, but it does mean the risk-to-benefit math isn't proven for healthy adults seeking "energy" and "cellular wellness."

If you're considering any form of NAD+ therapy, the things worth knowing are: the oral precursor data is real but mostly short-term and in specific populations; IV and injectable NAD+ lacks controlled trial data showing superiority over oral routes in healthy people; and compounded injectables carry sterility risks that oral supplements simply don't. Yoshino et al. (2021, Science) showed NMN improved muscle insulin sensitivity in postmenopausal women, which is promising but not a green light for everyone.

The take-home injectable concern the creator raises is legitimate and underreported. Patients self-administering compounded injectables without clinical supervision is a real harm vector. On that specific point, he's doing useful public health work.