For the years after sixty.
Staying strong, active and sharp-minded through your sixties, seventies and beyond. That is what this site is for. Everything on it — the blood markers, the tools, the evidence grades — exists to serve that one goal.
What we are aiming at
Living longer is not the point on its own. The point is arriving at seventy or eighty still able to do the things that make a life worth having — carry your own shopping, walk up a hill, follow a complicated argument, recognise everyone at the table.
That is a different target from treating disease, and it needs different information. A GP is looking for what has already gone wrong. This site is about the decades before that, when the things which will decide your seventies are already measurable and still movable.
A lab reference range describes the middle 95% of the people the lab sampled. It answers one question — do you look like most people? — and it answers it well. It was never designed to answer the question you are actually asking, which is where in that range people go on to stay healthy the longest.
Why the two ranges differ
A reference range is built by measuring a sample of people and taking the middle 95% of the results. It is a description of that sample. It is genuinely useful — it is how a lab decides whether to put a flag next to your number, and flags catch disease.
An optimal range is built the other way round. Cohort studies follow large groups for years, record what happened to them, and look back at what their numbers were. That produces a target drawn from outcomes rather than from the shape of a population.
Neither is wrong. They answer different questions, and the one your lab answers is not usually the one you were asking. Every marker page here shows both, with the source for each, so you can see the gap rather than take our word for it.
Optimal ranges come mostly from large observational studies, so they are targets rather than verdicts. Being outside one is a reason to look closer, not a diagnosis — and moving a number is not the same as changing an outcome.
Editorial standard
Every compound and protocol is graded against published human evidence, and the grade describes the strength of that evidence rather than how promising the mechanism looks. Sources are cited so you can check them. Where the evidence contradicts a popular claim, we say so — the scale below is only worth anything if things can score badly on it.
How this site is made
Research articles and compound profiles are drafted with AI assistance against primary sources — PubMed, journal publications and trial registries — and then checked and edited before publication. We think that is worth stating plainly rather than implying a clinical review board we do not have.
What that means in practice: treat this site as a well-sourced starting point and a set of calculators, not as clinical advice. Every page links its sources. If you find something wrong, we would rather hear it than not — corrections are made and dated.
What we do not do
We do not diagnose. We do not prescribe. We do not make medical claims. We translate the science — the rest is between you and a qualified physician.
How we grade evidence
Every compound and protocol on this site carries one of three grades. The grade describes the strength of the human evidence, not how promising the mechanism looks or how much we like it. Grades move when the literature moves — down as often as up.
- Grade AStrong human trial evidence
- Multiple randomised controlled trials in humans, ideally with a meta-analysis, showing a consistent effect on an outcome that matters — not just on a biomarker. Safety at the stated dose is well characterised.
- Grade BPromising but incomplete
- Some randomised human evidence, but the trials are small, short, conflicting, or measure surrogate endpoints. A reasonable bet with real uncertainty attached.
- Grade CMechanism, animals, or observation only
- The rationale rests on cell and animal work, on epidemiology, or on human trials that moved a biomarker without moving an outcome. Interesting, unproven, and priced accordingly.
A high grade is not a recommendation and a low grade is not a dismissal. Creatine and NMN are both worth understanding; only one of them has the trial record to back the claims made for it.