This is one of the few markers almost entirely determined by intake, which makes it unusually straightforward: unlike most biology, you can simply move it. The complications are dose, form and absorption rather than whether it will respond.
Target≥ 8 %
The longevity-optimised range used by the cognitive dial. See what omega-3 index measures for the reasoning.
What to expect, and when
Three to four months. Red cell turnover sets the pace and roughly 90% of the eventual change has happened by four months. Retesting before twelve weeks measures a transition in progress.
What works, in order of leverage
1. Eat oily fish two or three times a week
Salmon, sardines, mackerel and herring. The most reliable route, and it brings selenium, vitamin D and protein with it.
2. Supplement at gram-level doses if you do not
1–2 g of combined EPA and DHA daily moves the index measurably. The amount in a standard multivitamin or a 'fish oil' capsule marketed by volume does not — read the EPA+DHA figure, not the capsule size.
3. Take it with a fatty meal
Absorption of triglyceride-form fish oil is substantially higher with dietary fat. Taking it fasted wastes a large fraction of the dose.
4. Use algal oil if you are vegetarian or vegan
The practical option. ALA from flax, chia and walnuts converts to DHA at only a few percent and does not reliably raise the index.
5. Check the oil is not oxidised
Rancidity is common and counterproductive. A product that tastes strongly of fish usually is; store it cold and buy from suppliers who publish oxidation values.
6. Retest and adjust
Dose requirements vary several-fold between individuals. Measuring after four months is the only way to know yours.
Supporting supplements
Omega-3 (EPA+DHA) — high dose — 2–4g/day with foodevidence A
Structural brain component. Omega-3 Index <4% is one of the strongest modifiable cognitive aging risk factors. Target Index >8%.
Evidence tiers: A = consistent human trial support, B = mixed or mechanistic, C = early. Supplements support the changes above; they do not replace them.
What does not work
Worth knowing before spending effort on it.
Flaxseed, chia and walnuts as a substitute
They provide ALA, which converts to EPA at a few percent and to DHA at close to zero in most people. Valuable foods; not a route to a higher index.
Low-dose capsules
Several hundred milligrams of total fish oil may contain a fraction of that as EPA and DHA. The index does not move on it.
Judging a plasma fatty acid panel as the same test
Only red blood cell measurement gives the index. Plasma measures something different and is not interchangeable.
Retesting at six weeks
Red cells live about 120 days. An early retest shows a partial change and invites the wrong conclusion.
When to involve a clinician
High-dose omega-3 modestly increases bleeding time, which is worth raising before surgery or alongside anticoagulant or antiplatelet medication.
Not medical advice. These are longevity-optimised reference ranges, which are deliberately stricter than standard clinical "normal" values. A value outside them does not mean you have a disease. Speak to a qualified healthcare professional before changing medication, supplements or training. Full disclaimer.
Ask Us
Choose a question. Answers come from this site, and nothing you open is sent anywhere.
What is biological age?
Chronological age counts birthdays. Biological age estimates how old your body appears to be functioning, based on measurable biomarkers. Two people born the same year can differ by a decade or more in vascular stiffness, insulin signalling or cardiorespiratory fitness. Biological age makes that gap explicit — and unlike your birthday, it can move in either direction.
How is the Longevity Score calculated?
Each biomarker you enter is scored against longevity-optimised reference ranges and grouped into one of eight dials. Every dial produces its own biological age, and those are combined using fixed weights into a single composite, then expressed as a Longevity Score from 0 to 100. The weighting reflects how strongly each system predicts healthspan: structural and vascular carry the most, hormonal the least.
Do I need all 53 biomarkers?
No. The short form contains a subset of scoring inputs plus context-only fields, and you can leave any of them blank. It is not a recommendation to obtain tests. Missing values are excluded from the calculation — never treated as zero or as 'normal'. A dial with no scored data is dropped entirely and the remaining weights renormalise.
What can I measure without a blood test?
Some inputs can be measured without bloodwork. Blood pressure needs a home cuff and waist-to-height needs a tape measure. Wearable estimates vary; the floor-based sitting-rising test carries a fall risk and should only be attempted if safe.
Is this an anti-aging calculator? Is it a healthspan calculator?
Both terms describe what this tool does, and which one fits depends on what you are asking. "Anti-aging" is the term most people search, and loosely means anything aimed at slowing or reversing age-related decline — this tool fits that description if you score your dials and act on what you find. "Healthspan calculator" is the more precise term: healthspan is the number of years lived without serious chronic disease or disability, and that cannot be measured directly, so this tool scores eight systems that each function as an early-warning proxy for it. Either way, the method is the same: real biomarkers, published thresholds, no vanity-metric framing.
Why don't you have a quick quiz that skips biomarkers entirely?
Several popular tools ask only about habits — exercise days, sleep hours, smoking, diet quality — and return a single precise-looking age. We looked at the research behind that approach and chose not to build it. Published studies do show real, individually-measured links between specific habits and epigenetic age acceleration, but those effect sizes come from different study populations, different DNA-methylation clocks and different measurement units. Adding them together into one number is not something the underlying research actually supports — it produces a precise-looking result built on an imprecise method. Our dials use direct physiological measurements instead: a real blood pressure reading, a real VO₂ max, a real ApoB value. Several dials score from home-measurable data alone with no quiz-guessing involved — see what you can measure without a blood test, above.
Why are your 'optimal' ranges stricter than my lab's normal range?
Standard reference ranges describe what is common in a general population, which now includes a great deal of metabolic dysfunction. They are tuned to flag disease, not to identify what is optimal for a long healthspan. A fasting insulin of 20 µIU/mL sits inside most labs' normal range and is strongly associated with insulin resistance. This tool uses longevity-optimised thresholds instead, so a flag here means room for optimisation — not a diagnosis.
Why not just upload my labs to ChatGPT?
For understanding a single result, do — a frontier chat model is genuinely good at that, often clearer than most medical sites, and it handles markers no fixed tool covers. The limitation is different from the one most people assume. A language model produces a plausible response rather than a computed one, so the same panel can score differently on different days. That is fine when exploring an idea and disqualifying when measuring change, because you cannot tell how much of a difference is you and how much is the method. Use both: a chat model to understand, a fixed instrument to track.
Is my health data private?
Biomarker values, assessment history and visit-preparation drafts are stored in your browser. The visit draft is separate from assessment exports and share links; copying or printing it can leave a copy outside the browser. There are no user accounts or third-party tracking. We keep anonymous usage totals on our own server, such as how many people reached a results screen on a given day; browsers sending Do Not Track or Global Privacy Control are not counted. Optional lab-report upload and AI coach features send data to Anthropic. Optional retest reminders send an email address, date and reminder label to our service and email provider. See our privacy policy for details.
Is this a medical diagnosis?
No. It is an educational and personal-tracking tool. The estimates are not clinically validated and must not replace evaluation by a qualified healthcare professional. If a result concerns you — particularly kidney markers, blood pressure or ApoB — take it to a doctor rather than acting on it alone.