What is a longevity clinic, in 2026?

The phrase longevity clinic is, in 2026, doing too much work. It is being used to mean a residential health resort with fasting protocols. It is being used to mean a Mayfair functional-medicine practice. It is being used to mean a $199 direct-to-consumer biomarker subscription. It is being used to mean a Mediterranean stem-cell franchise.

These are not the same product. Treating them as one category does the reader a disservice. So at the risk of sounding officious about a recently-coined word, here is the working definition we use across this directory.

A working definition

A longevity clinic, as we use the term, is a medical practice that:

1. Operates a physical clinical site with at least one full-time MD on the staff
2. Runs a diagnostic workup as the substantive entry point — bloodwork, imaging, functional testing, or some combination — rather than a treatment menu as the entry point
3. Designs a longitudinal protocol from the diagnostic findings, with structured follow-up across at least the next twelve months
4. Treats healthspan extension as the work, rather than disease treatment after the fact

The first three items are the necessary conditions. The fourth is the differentiator from executive medicine, which has done parts of this for decades but framed it differently.

What this excludes

Direct-to-consumer biomarker memberships — Function Health, Superpower — are not longevity clinics under this definition. They are diagnostic services that lack the physical site, the MD-led clinical relationship, and the longitudinal protocol design. We review them in the directory because the reader is choosing between them and the clinics; we are clear they are a different product.

Residential resorts that are primarily fasting and bodywork programmes — many of the European spa-medicine destinations — sit at the edge of the definition. We include the ones with a substantive medical core (Lanserhof, Clinique La Prairie). We exclude the ones where medicine is essentially decorative.

Imaging-only practices — Prenuvo — are not longevity clinics. They are screening services. We review them in the directory because the imaging is meaningfully relevant to the longevity question. We are clear they are partial.

Stem-cell, peptide, or hormone clinics that lack a comprehensive diagnostic intake — we do not review at all. They are treatment franchises wearing longevity branding. The reader is welcome to disagree; we believe the distinction matters.

Three diagnostic loops

A clinic that meets the working definition runs, in some form, three diagnostic loops.

The intake loop is the comprehensive baseline: imaging, bloodwork, functional testing, sometimes genomics. Our editorial bar for the upper-tier clinics is that the intake produces a meaningful new clinical decision in at least one in three patients — meaning it surfaces something a thoughtful generalist would not have surfaced from the standard executive workup.

The protocol loop is the design phase: the clinician translates the intake into a personalised twelve-month plan covering training, nutrition, sleep, supplementation, and where indicated, pharmacology. The protocol is specific — dosed, scheduled, measurable — or it is decoration.

The review loop is what most clinics fail at: the structured follow-up, three months later, six months later, twelve months later, with re-assessment, protocol revision, and a clinician who remembers your case. This is the loop that decides whether the cheque was worth writing. The clinics that take it seriously are a small subset.

Why the format split exists

The category divides into two formats with different jobs.

Residential — multi-day to multi-week stays — is the right format for the patient who wants the work delivered. The diagnostic, the early protocol, the supervised initial weeks. The Swiss/Austrian/Italian residential tradition is the older form of this. It suits the post-fifty patient with the time and the budget, particularly post-event (recovery, transition, change of pace).

Outpatient — single-day diagnostics with structured follow-up — is the format for the patient who already trains, sleeps and eats well, and wants the diagnostic spread without the spa overlay. Berlin, London, New York, Singapore lead on diagnostic depth. The work happens in the year that follows the day, not on the day itself.

We have argued elsewhere that most readers under fifty are better served by a sharp outpatient day plus a structured twelve-month follow-up than by a residential week. This remains our position.

What it costs

A serious longevity clinic, in 2026, costs:

• €2,000–17,000 for a single comprehensive outpatient day (YEARS Core through Ultimate)
• CHF 25,000–80,000 for a 7–21 day residential stay (Swiss tradition)
• USD 14,500–32,500 per year for a membership concierge model (Early Medical, Biograph)
• USD 199–499 per year for a direct-to-consumer biomarker subscription (Superpower, Function)

The price spread reflects genuinely different products, not arbitrage. A $499 subscription and a $32,500 membership are not buying the same thing at different price points. They are buying different things.

What it is not

Anti-ageing. No clinic in this directory has demonstrated that its protocol extends lifespan in randomised data on humans. The honest framing is evidence-based healthspan optimisation — risk stratification, early detection, and lifestyle protocol design that the published evidence supports.

Clinics that frame their work as anti-ageing or biological age reversal — as a primary marketing claim, rather than as a measurement — are claiming more than the data supports. We deduct points for this in our scoring rubric.

The bottom line

A longevity clinic, in our working definition, is a serious medical practice doing structured prevention with a longitudinal cadence. There are perhaps thirty such practices worldwide that meet the bar. We are reviewing fifteen of them in this directory and adding more monthly.

The category is real, the work is serious, and the reader is right to be careful. The marketing is louder than the medicine in too many cases. The directory exists to help you tell them apart.