How your Health Age is worked out

We start from your real age, then add or subtract years based on your answers about how you live. The result is your Health Age.

It is an estimate built only from what you tell us. It is not a medical test, it does not measure biological age in a laboratory sense, and it cannot diagnose anything.

Nine things: your body measurements, sleep, water, movement, digestion, stress, smoking, alcohol and diet.

Each answer carries a value in years. Smoking carries the most weight by a wide margin, which reflects how strongly it is linked to health outcomes and how quickly that risk falls after stopping.

Some combinations count for more than the sum of their parts. Short sleep together with high stress, for example, is treated as worse than either alone.

Your biological sex adjusts the starting point slightly, reflecting the average difference in life expectancy. It is optional.

The areas you tap on the body map do not change your Health Age. They decide what we suggest afterwards, and nothing else.

The extra question we sometimes ask about your weakest area does not change it either. It only makes the advice more specific.

Nothing you buy from us changes it. The number responds to your answers, not to your order history.

Every result carries a range, shown as plus or minus a number of years. That range narrows when you give us more to work with, such as your waist measurement.

The year values are informed by published research on lifestyle and longevity, then rounded and kept within believable bounds so that no single answer produces an absurd result. They are deliberately conservative.

Two people who answer identically will always get the same number. The calculation does not vary by person, by day, or by anything we know about you commercially.

It is not a diagnosis, a screening test, or a substitute for seeing a doctor.

It cannot detect a condition, and a good Health Age does not mean you are well. If something is worrying you, that is a conversation for a clinician, not a quiz.

It is designed to make the effect of everyday habits visible and worth acting on. That is the whole ambition.

You can see the number without an account. Nothing is stored until you choose to save it, and saving asks for your consent first.

Health Age is for adults. We do not save results for anyone under 18.

You can delete your saved results at any time from your account.

If we change how the number is calculated, we record it as a new version and leave your past results exactly as they were.

Recalculating your history to match a newer method would make your own progress impossible to trust, so we do not do it.