Increasing NAD+ levels via precursors like nicotinamide riboside (NR) helps support mitochondrial function and sirtuin activity, thereby helping to counteract the effects of age-related decline.

mixed

It is well established in the scientific literature that NAD+ levels decrease with age, which affects cellular metabolism and DNA repair mechanisms.

noli's read

It is well established in the scientific literature that NAD+ levels decrease with age, which affects cellular metabolism and DNA repair mechanisms. Human clinical studies (randomized controlled trials) confirm that NR or NMN supplementation does effectively increase circulating NAD+ levels. The idea that this boosts the activity of sirtuins, NAD+-dependent enzymes involved in cellular health, is based on solid evidence from animal and cellular models. However, extrapolating these results to claim a direct improvement in longevity or overall mitochondrial function in healthy humans remains an area of uncertainty. While safety evidence is encouraging, concrete long-term functional benefits still require broader clinical data. The link is therefore mechanistically consistent, but the magnitude of the therapeutic effect in humans is sometimes overinterpreted in popular discourse.

the sources

Claimed by Rhonda Patrick (FoundMyFitness). Noli grades the claim, never the person.

Decoded by Noli · July 18, 2026 · the original post

What the graded evidence says

Effect: CVD/cancer prevention in replete adults (VITAL) — no significant reduction
Measured on: VITAL: 25,871 adults

Great for correcting a deficiency; weak as a general preventive if you're already replete.

Noli has read similar claims

Other advice in the Register that leans on the same research.

Extreme, prolonged sun deprivation — like months aboard a nuclear submarine — is exactly the scenario where routine vitamin D supplementation makes real sense: several studies on submarine crews (Royal Navy, US Navy) show levels drop markedly within weeks without it.

holds upPaul McNally

For women in their 20s: four basics are enough — omega-3, vitamin D3, magnesium glycinate, and a quality probiotic — rather than 15 supplements.

mixedThebiohackingrn

Dr. Gominak's theory — that low vitamin D disrupts the gut microbiome, which then stops making enough B vitamins, which then breaks sleep — comes from a single practitioner who herself acknowledges the mechanism hasn't been confirmed by other research teams: an interesting lead, not (yet) established evidence.

not provenThe Diary Of A CEO

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