The information overload problem
NMN. Rapamycin. Metformin. Red light therapy. Cold plunging. The longevity space generates more information than almost anyone can navigate, and for most people the result is either paralysis or a supplement drawer full of expensive capsules with no clear rationale. The evidence, however, points to a simpler answer. The largest longevity gains come from a handful of well-studied interventions — most of them free, all of them unsexy, and none of them requiring a prescription.
Start with lifestyle — the evidence is clear on the hierarchy
Before any supplement is worth considering, three lifestyle pillars carry most of the weight. A 2024 SLEEP journal study of 60,977 UK Biobank participants found that sleep regularity — consistent sleep and wake times — is a stronger predictor of all-cause mortality than sleep duration, with higher regularity associated with 20–48% lower mortality. A 2024 meta-analysis on resistance training found just 60 minutes per week is associated with 15% lower all-cause mortality and 19% lower cardiovascular mortality, with a U-shaped dose-response suggesting more is not always better. And a 2024 overview of 199 cohort studies (20.9 million observations) found each 1-MET improvement in cardiorespiratory fitness reduces all-cause mortality by 11–17%. These effects are large, consistent across populations, and accessible to almost everyone.
The three non-negotiables — consistent sleep timing, 60 minutes of resistance training per week, and 150+ minutes of Zone 2 cardio — produce larger longevity gains than any supplement stack yet studied in humans.
The evidence-based supplement starter stack
Once lifestyle fundamentals are established, a small set of supplements have sufficient clinical evidence to warrant consideration for healthy adults. The selection below prioritises effect size, trial quality, safety, and cost-effectiveness — not marketing spend.
Omega-3 fatty acids (EPA/DHA) — 1,000–2,000mg daily
Omega-3s have one of the strongest supplement evidence bases in existence. A 2025 systematic review by Mattumpuram and colleagues covering 42 studies and 176,253 participants found significant cardiovascular mortality reduction with supplementation. A 2024 meta-analysis of 18 RCTs (134,144 participants) found cardiovascular death relative risk of 0.92. There is growing evidence that EPA monotherapy may have an edge over standard EPA+DHA combinations for cardiovascular endpoints, though both are beneficial. Australian cost: approximately $20–30 per month for a quality formulation.
Magnesium — 200–400mg daily (if deficient)
A 2024 global review found 31% of the world's population falls below adequate magnesium intake — in Australia, deficiency is likely common in people with high-processed food diets, those who drink alcohol regularly, and older adults. Deficiency is associated with hypertension, type 2 diabetes, poor sleep quality, and sarcopenia risk. Glycinate is generally the best-absorbed form with the fewest gastrointestinal side effects; threonate is better studied for cognitive effects. Check your serum magnesium level first — if you are deficient, correcting it matters more than the specific form. Australian cost: approximately $5–15 per month.
Creatine monohydrate — 5g daily
Creatine is one of the most studied compounds in sports science, but its longevity applications are increasingly recognised. A 2025 systematic review found 83% of studies showed positive associations between creatine supplementation and cognitive outcomes in older adults, with improvements in memory, processing speed, and attention. When combined with resistance training, creatine significantly improves muscle strength and lean mass — directly addressing sarcopenia, one of the major contributors to functional decline with age. It is inexpensive, well-tolerated with no serious adverse events over long-term use, and broadly available. Australian cost: approximately $5–10 per month.
Vitamin D3 — 2,000 IU daily (for specific populations)
The 2024 Endocrine Society Clinical Practice Guidelines narrowed the routine supplementation recommendation: healthy adults under 50 with adequate sun exposure do not benefit from empiric vitamin D supplementation. The picture changes for adults over 75 (where supplementation is associated with mortality reduction), people with prediabetes, pregnant women, and those with confirmed deficiency. Before supplementing, check your 25-hydroxyvitamin D level — if you are above 75 nmol/L, supplementation is unlikely to add much. If you are below 50 nmol/L, 2,000 IU daily is a reasonable correction dose. Australian cost: approximately $5–10 per month.
Total monthly cost for the evidence-based starter stack (omega-3, magnesium, creatine, vitamin D if needed): approximately $35–60 AUD — compared to $150–300/month for trendy longevity compounds with substantially weaker clinical evidence.
What to skip despite the marketing
Multivitamins are the most instructive cautionary tale. A 2025 Johns Hopkins review confirmed what most rigorous reviews have found: no proven benefit for heart disease, cancer, cognitive decline, or all-cause mortality in otherwise healthy adults. Similarly, probiotics for the general healthy population are not recommended by the American Gastroenterological Association (2025 guidance), which found insufficient evidence for their use outside specific clinical contexts. Ginkgo biloba, despite decades of marketing, failed to reduce dementia rates in a 6-year RCT of 3,000 older adults. NMN and NR are more nuanced — the evidence is genuinely promising but premature, the cost is high, and the lifestyle foundations matter far more.
A practical daily protocol
With breakfast: omega-3 (fat-soluble absorption improves with food) and creatine 5g (timing is flexible — consistency matters more). With dinner or 30–60 minutes before bed: magnesium glycinate 200–400mg (supports sleep quality and relaxation). Vitamin D3 with any fatty meal if indicated. This takes under a minute, costs less than a daily coffee, and covers the evidence-based bases.
The bottom line
Longevity is not a supplement problem — it is primarily a lifestyle problem. Sleep regularity, resistance training, and aerobic fitness together account for the overwhelming majority of evidence-based longevity benefit. Supplements play a supporting role: omega-3, magnesium, and creatine are the best-supported additions for most people. Save the exotic compounds for when you have the lifestyle foundations dialled in and are working with a physician who understands the current evidence. Consistency with the basics beats optimisation of the margins, every time.
References
- Windred, D. P., et al. (2024). Sleep regularity is a stronger predictor of mortality risk than sleep duration (n=60,977). SLEEP, 47(1).
- American Journal of Preventive Medicine (2022). Resistance training and all-cause, CVD, and cancer mortality: dose-response meta-analysis.
- Overview of meta-analyses (2024). Cardiorespiratory fitness and mortality: 199 cohort studies, 20.9M observations.
- Mattumpuram, J., et al. (2025). Omega-3 fatty acids and cardiovascular mortality: systematic review of 42 studies, 176,253 participants. Clinical and Translational Discovery.
- Global review of magnesium adequacy (2024). 31% of global population below adequate intake.
- Nutrition Reviews (2025). Creatine supplementation and cognition in older adults: systematic review.
- Endocrine Society (2024). Clinical Practice Guideline: Vitamin D for the Prevention of Disease.
- Johns Hopkins Medicine / JAMA (2025). Multivitamins and health outcomes in healthy adults: no proven benefit for mortality, CVD, cancer, or cognitive decline.
- American Gastroenterological Association (2025). Clinical practice update on probiotics.
- Critical Reviews in Food Science and Nutrition (2024). NMN supplementation meta-analysis: 12 RCTs, 513 participants.