Longevity Supplements: What Works, What Doesn't, and What's Just Marketing

What has real human evidence

Vitamin D corrects a genuinely common deficiency, and correction is associated with fewer falls and fractures in older adults. Testing beats guessing; megadosing has no benefit and intermittent high doses have shown harm.

Omega-3 fatty acids have the largest evidence base of any supplement here, with cardiovascular risk-marker improvement and mixed but suggestive cognitive data, particularly at intakes most people do not reach from diet.

Creatine monohydrate is the surprise entry on a longevity list. In older adults combining creatine with resistance training, lean mass and strength gains consistently exceed training alone, and muscle mass is one of the strongest predictors of independence in later life. It is also cheap and among the most studied compounds in sports nutrition.

Protein: the supplement most people actually need

Anabolic resistance means older adults require a larger protein dose per meal — around 40 g rather than 25 g — to produce the same muscle protein synthesis response. Appetite typically declines at the same age, which is a bad combination.

This is the least exciting and most impactful intervention on the list. If protein intake is under 1.2 g/kg and there is resistance training in the picture, closing that gap will do more than every exotic compound combined.

Collagen, joints and skin

Randomized trials of hydrolysed collagen peptides at 2.5–10 g daily over 8–12 weeks show small but consistent improvements in skin elasticity and hydration, and reductions in activity-related joint discomfort in athletes and older adults.

Mechanistically, collagen peptides are not deposited intact; the working hypothesis is that specific di- and tripeptides signal fibroblast activity. Treat it as a modest, low-risk addition rather than a structural intervention.

The NAD+ family: promising, unproven

NAD+ declines with age, and NMN and NR both raise circulating NAD+ in human trials. That is where the human story currently stops — the trials measuring clinical ageing outcomes have either not been run or have not shown effects.

The precedent worth remembering is resveratrol, which produced a similar wave of enthusiasm from sirtuin activation data, and whose central findings failed to replicate. Biomarker movement is a reason to keep studying a compound, not a reason to spend $90 a month on it.

The whole-food alternative

The pattern across the failures — beta-carotene, vitamin E, resveratrol — is that isolating a compound at a pharmacological dose behaves differently from eating the food that contains it. The pattern across the successes is that they correct a deficit rather than push a system beyond normal.

That is the practical case for a whole-food herbal base: it is a way of raising the floor across many nutrients at once, in food form, daily, instead of betting on a single molecule with an eight-week biomarker trial behind it.