Function Health.

What Function actually is

A consumer-priced lab-testing membership, headquartered in the US, with Mark Hyman as Chief Medical Officer. The proposition is the price floor: $499 a year for an annual 100+ marker blood panel plus a 60+ marker follow-up panel six months later, with a usable dashboard wrapping it.

Function is not a clinic in the sense the rest of this directory is. There is no whole-body MRI, no CPET-grade VO₂ max, no in-person physician relationship, no protocol design beyond the dashboard’s interpretive notes. The product is the bloodwork plus the interpretation layer.

What it does well

Three things, on their own terms.

Price disruption. The $499/year price point is a structural shift in what comprehensive biomarker access costs. The same bloodwork, ordered at-cost in a US executive-medicine setting, runs into four-figure territory. Function has decoupled the lab work from the clinical relationship and priced accordingly.

Conflict structure. No treatment products. No supplement upsells. No in-house pharmacy. The financial geometry is the membership itself, full stop. This is structurally cleaner than every clinical practice in this directory except Prenuvo.

The dashboard. Reference-range comparisons, longitudinal tracking across panels, and short explanatory copy on each marker make the product usable for a numerate motivated reader who knows what they are looking at.

What it is not

Function is not a substitute for clinician-led longevity care.

There is no physician reviewing your panel and translating it into a personal protocol. There are interpretive notes, but interpretation is not consultation; the difference matters most where it matters most — for a borderline finding that could mean three different things depending on context.

There is no imaging. Whole-body MRI, cardiac calcium, brain imaging — the highest-yield findings in the longevity workup — are not in scope.

There is no functional testing. CPET, DEXA, body composition, sleep architecture — all absent.

For the reader who genuinely wants a longevity workup, Function is a component, at best — useful as the bloodwork layer beside an imaging service like Prenuvo and a clinical relationship at the upper tier. As a standalone product, it is half a workup.

Where the evidence question lives

Less in unproven therapies — there are none — and more in marker selection and reference-range methodology. Some markers in the panel have well-established clinical actionability (lipids, HbA1c, ApoB if included, hsCRP). Others are included for completeness with weaker evidence on what optimal really means in an asymptomatic adult. The dashboard is generally honest about this distinction.

The verdict

For the budget-conscious motivated reader who wants annual bloodwork at a price the category had not previously accepted, Function is a real option. For the reader looking for a longevity clinic in any of the senses the rest of this directory uses the word, Function is a complement, not a substitute.

A diagnostic without a clinician is a different product to a diagnostic with one. Function is the first; the rest of this directory is mostly the second.