Three tiers, not a rating
Just how much you can trust the evidence behind each one — not which is "best," and never medical advice. Click a tier to jump straight to it.
TIER 1
Foundational Essentials
Fills a genuinely common nutrient gap with strong, replicated human evidence. Worth ruling out a deficiency before considering anything higher up this page — see the comparison page for blood tests that check these directly, and the glossary for what each blood marker actually measures.
Vitamin D3 + K2Strong evidence
Supports bone density and immune function; D3 deficiency is common even in sunny climates, and K2 helps direct calcium to bone rather than soft tissue. See the glossary for what a vitamin D blood test actually measures.
Typical form: softgel / dropsSample dosage: 1000–4000 IU D3/day
→ 3 of 4 tracked experts with a published stack independently take this — see the Thought Leaders consensus
Magnesium (glycinate/threonate)Strong evidence
Involved in over 300 enzymatic processes; commonly under-consumed even in otherwise healthy diets. Glycinate and threonate forms are better absorbed and gentler on digestion than cheaper oxide forms.
Typical form: capsule / powderSample dosage: 200–400mg/day
Omega-3 (EPA/DHA)Strong evidence
One of the most-studied supplement categories — consistently linked to cardiovascular and inflammatory marker improvements. Quality and concentration vary hugely between brands.
Typical form: fish oil / algae oilSample dosage: 1–2g combined EPA+DHA/day
→ 3 of 4 tracked experts with a published stack independently take this — see the Thought Leaders consensus
TIER 2
Systemic Support
Broader claims than Tier 1, with moderate — not conclusive — human evidence. Reasonable to consider once the basics are covered, not before.
Creatine monohydrateModerate evidence
Helps preserve muscle strength and mass with age — but only alongside resistance training, not instead of it. See our research page for the actual meta-analysis behind this.
Typical form: powderSample dosage: 3–5g/day
→ 3 of 4 tracked experts with a published stack independently take this — see the Thought Leaders consensus
CoQ10Moderate evidence
Supports mitochondrial energy production; often taken alongside statins, which are known to deplete natural CoQ10 levels. Human outcome data beyond blood markers is still limited.
Typical form: softgel (ubiquinol form)Sample dosage: 100–200mg/day
TaurineModerate evidence
An amino acid of growing research interest for metabolic and cardiovascular health; animal studies are further along than human trials at this point.
Typical form: powder / capsuleSample dosage: 1–3g/day
CurcuminModerate evidence
The active compound in turmeric, studied for anti-inflammatory effects.
Note: curcumin is poorly absorbed on its own in most human trials — bioavailability-enhanced formulations (e.g. with piperine or as a phytosome) show meaningfully different results to plain turmeric extract. This matters more here than for most Tier 2 entries.
Typical form: capsule (look for bioavailability-enhanced)Sample dosage: 500–1000mg/day
TIER 3
Targeted Longevity Agents
The most speculative tier on this page. These target specific cellular aging pathways with real mechanistic interest, but human longevity-outcome data is early or entirely absent — this is where marketing claims most often outrun the actual research.
NMN / NR (NAD+ precursors)Early evidence
Aim to raise NAD+, a molecule involved in cellular energy metabolism that declines with age. Human trials so far mostly show changed blood markers, not proven longevity or healthspan outcomes.
Regulatory status in the US: in a Sep 29, 2025 response to a citizen petition, the FDA concluded that NMN "is not excluded from the definition of dietary supplement," reversing the position it took in October 2022. Its reason: NMN was sold as a dietary supplement in the US (as early as 2017) before it was authorized for investigation as a new drug. The FDA also treats NMN as a new dietary ingredient, which generally means a supplier has to notify the FDA, with its safety evidence, before selling it. The letter is about legal status only; it doesn't assess whether NMN is safe or effective.
FDA response letter (docket FDA-2023-P-0872) · checked Oct 10, 2026
Typical form: capsule / powderSample dosage: 250–500mg/day
→ Single-mention pick (David Sinclair only, alongside resveratrol) — see the Thought Leaders consensus
Urolithin AEarly evidence
Targets mitophagy (cellular "cleanup" of damaged mitochondria). Has some real human trial data on muscle function specifically — more than most entries in this tier — but still an emerging area overall.
Typical form: capsuleSample dosage: 500–1000mg/day
SpermidineEarly evidence
Studied for its role in autophagy, the body's cellular recycling process. Mostly preclinical and small-scale human data so far — genuinely interesting mechanism, not yet a proven outcome.
Typical form: capsule (often wheat-germ derived)Sample dosage: 1–5mg/day
Straight answers, sourced
Is anything on this page medical advice?
No. This page describes, at a population level, what a supplement generally does and how strong the evidence behind it is — it never interprets what any of this means for you personally, and never recommends what you specifically should take. A doctor or specialist reviewing your own blood results can tell you things about your own body — including when a supplement that's fine for most people isn't right for you — that a general page like this can't. See our
guide for more on why that's one of the real benefits of full-service programs.
How are the three tiers decided?
By evidence strength, not popularity or price. Tier 1 fills a common, well-documented nutrient gap with strong, replicated human evidence. Tier 2 has moderate — real but not conclusive — human evidence for broader claims. Tier 3 targets a specific cellular aging pathway with genuine mechanistic interest, but human longevity-outcome data is early or absent. Where evidence is mixed within a tier (curcumin's absorption problem, for example), that's called out directly rather than smoothed over.
Where are the all-in-one products?
On their own page.
All-in-one supplements, compared breaks down four pre-made stacks sold in the US using these same three tiers, ingredient by ingredient, alongside price per 30 days and the third-party testing each brand states. It also covers what FDA and FTC rules mean for supplement labels and claims.