The longitudinal disk
for longevity medicine.
Longevity patients generate more biomarker data than any other cohort in medicine. CGM, HRV, quarterly bloodwork, genomics, wearables, imaging, supplement logs, training load, sleep, journal. Every number matters. Every number is scattered across six portals.
We hold the shape. You keep the data. harnesshealth.ai is a local disk for the longitudinal record a longevity patient actually generates — every clinician in your stack can read it, no clinician can own it, no AI can keep it.
Because decade-plus care is architecturally hostile to vendor-held data. Nothing on this page has shipped yet; the dashboard is a sample-data preview.
The pre-institutional moment
Longevity medicine today is where public health was in 1890.
Enough scientific foundation to be serious. Not enough institutional infrastructure to be systematic. A credibility spectrum that runs from Nobel-caliber research to Instagram coaches. No board certification. No residency. No agreed scoreboard for what aging well even looks like.
Public health's early wins came from removing harms — clean water, vaccines, nutritional deficiency. The architectural harm we can remove in longevity medicine today is fragmented, vendor-held, non-longitudinal data. That's the first institution the field needs.
harnesshealth.ai is the substrate. What gets built on top of it — AI-assisted synthesis, trial enrollment, shared longitudinal cohorts, credentialed clinical pathways — needs the disk first.
What sits on the disk
Every layer of a longevity patient's life, in one place, on their hard drive.
FHIR-formatted where the standard exists. Open schema where it doesn't yet. Exportable as one bundle into Claude, ChatGPT, Gemini — or your clinician's review screen.
Continuous biomarkers
CGM streams, HRV, resting HR, sleep stages, training load. Whoop, Oura, Garmin, Apple Health, Levels, Libre — all land in one timeline, not six.
Clinical bloodwork
Quarterly panels, advanced lipids, hormones, inflammatory markers, micronutrients. From any lab, any clinician, any panel — harmonized into a longitudinal record.
Genomics & omics
Whole-genome, exome, microbiome, proteomic and metabolomic panels. Held once, referenced forever. Never re-ordered because the old result lived in a portal that sunsetted.
Imaging
DEXA, coronary calcium, whole-body MRI, brain volumetrics. Reports and quantitative outputs, not just the PDF.
Cognitive & functional
VO₂max, grip strength, cognitive test scores, balance, gait. The benchmarks that actually track healthspan, stored alongside the labs.
Journal, supplements, plan
What you're taking, what your clinician recommended, what you tried, what worked. A structured log any AI can read to answer “what changed?”
Status: the schema is designed and no connector has shipped; this page is an architecture brief, not a product you can install today. Apple Health and FHIR R4 (Cures Act patient API) are the first ingest paths. Whoop, Oura, Levels, InsideTracker, and genomics vendors follow.
Why longevity patients first
Five reasons longevity is the sharpest first vertical for a user-owned health disk.
Decade-plus longitudinal by design
The whole point is tracking trends, not snapshots. Vendor-held data fragments the moment a platform pivots. A local disk is the only architecture that matches the care model.
Multi-clinician coordination is the norm
Primary, endocrine, nutrition, performance coach, therapist, sometimes integrative and functional. Each holds a slice. Nobody holds the shape. The disk is the shape.
Out-of-pocket willingness-to-pay
Longevity care is largely cash-pay. Willingness to pay for infrastructure that serves the patient — not the billing chain — already shows up in what this cohort pays for out of pocket.
The most AI-fluent patient cohort in medicine
They're already using Claude, ChatGPT, Gemini to interpret their own labs. They need the context to be transportable because they're already moving between AI brains.
Highest-density data generators alive
A 45-year-old in a longevity program can produce more biomarker data per year than a 70-year-old chronic-disease patient. Somebody needs to hold it all. Currently nobody does.
The case in one disease
Two specialists, one signal — and the patient is the only integration layer.
In metabolic liver disease (MASLD), the leading cause of death is not the liver — it is the cardiovascular disease the same metabolic biology is building in parallel. ApoB, Lp(a), HOMA-IR, and coronary calcium on one side; FibroScan and hepatic imaging on the other. A hepatologist and a preventive cardiologist are reading different windows into the same room.
And the practical warning writes itself: a patient cannot assume one specialist knows what the other has found, because the clinical infrastructure for that communication rarely exists. So the person carrying the complete picture between the liver clinic and the cardiology clinic is the patient, armed with printouts.
That is not a staffing problem or a software-vendor problem. It is what the absence of an owned, longitudinal record looks like from inside an exam room — and it is exactly the gap the disk closes.
The architecture already won — in your house
Home Assistant proved local-first works. Health is next.
The most successful smart-home platform is the one that keeps your data in your house: over a thousand device integrations, everything processed locally, no cloud required, the user holding the keys — governed by a nonprofit, the Open Home Foundation. It did not win by having the best AI. It won by making ownership the architecture instead of the promise.
The longitudinal disk is the same bet for the body. The record lives with you — anchored, portable, verifiable — and the models, the apps, and the specialists come to it, under your consent. Vendors rotate on a two-year cycle. The thing that stays local and stays yours is the thing that accumulates.
For longevity clinicians
Your patients show up with a readable record. You stop re-ordering panels that already exist.
harnesshealth.ai is patient-held infrastructure, not a clinic platform. We do not compete with your EHR, your coaching software, or your labs. We hold the longitudinal record the patient generates across your care — and every other clinician's — so the next appointment begins from context, not from scratch.
Open schema, not a walled garden
FHIR R4 where the standard covers it. Open, documented schema where it does not — wearables, continuous biomarkers, supplement regimens, subjective journals. No proprietary format. No extraction fee. No risk of the data being held hostage if the patient leaves your practice.
Local-first, patient-owned
The disk lives with the patient — on device, in their own storage, under their own keys. Clinicians get read access per patient-granted share link. No cloud tenant to audit, no BAA to negotiate for a record the patient already owns.
Any AI can read. None can keep.
The patient can load the bundle into Claude, ChatGPT, Gemini, or a local model for interpretation. The model sees the data inside the conversation. It does not retain a copy. The disk is the durable layer; the AI is the transient interpreter.
Attestation layer, optional
If an AI-generated interpretation is acted on clinically, a licensed physician can review and sign it. The attestation is attached to the record, not the AI output. Clinical authority stays with the clinician. The disk just holds the receipt.
What this replaces in your workflow
The intake form that re-asks everything. The second panel you ordered because the first lived on a portal that sunsetted. The 40 minutes of a consult spent recovering history you should have started with. The decade of data that evaporates the moment a patient changes clinicians.
Early access
Hold your own longevity record.
We're looking for the first cohort of longevity patients and clinicians. If you work with a longevity practice — or run one — claim a profile and start building the disk.
Longevity is the first vertical. The same disk works for any cohort that generates more longitudinal data than their EHR can hold.