LACE編集部 · 公開日
Chronological age is the number of years since you were born. Biological age is an estimate of how old your body appears to be, based on measurable markers. A biological age test produces that estimate from blood or saliva. The idea is sound and the science is real, but a single result is far less precise than the number on the report suggests.
Biological age and chronological age
Two people born in the same year can differ greatly in health. One has the arteries, muscle and metabolism typical of someone ten years younger; the other, ten years older. Biological age is an attempt to put a number on that difference, so that it can be tracked and, ideally, changed.
How the tests work
There are three main families.
- Epigenetic clocks read chemical tags on DNA, called methylation, at hundreds of sites that change predictably with age. The first widely used clock was published by Steve Horvath in 2013. Later versions, such as GrimAge and DunedinPACE, were trained on health outcomes and on the pace of ageing instead of on calendar age.
- Blood-marker clocks, such as PhenoAge, calculate an age from routine laboratory values including glucose, inflammation and kidney and liver markers.
- Functional measures are not sold as age tests but arguably tell you more: VO2 max, grip strength, walking speed and body composition.
How reliable are they?
At the level of large groups, the clocks work: people with a higher biological age than their calendar age are, on average, at greater risk of disease and earlier death. At the level of one person and one test, the picture is weaker. The same sample analysed twice can return results a year or more apart, and results shift with the time of day, a recent illness or which laboratory ran it.
Two consequences follow. A single test is a rough indication, not a diagnosis. And a change of a year or two between two tests may be noise. No clock has yet been validated as proof that a treatment extends life, so a product advertised as having reversed biological age has shown that it moved a number.
When a test is worth taking
A biological age test is most useful as one reading among many, repeated under the same conditions over years, and interpreted by a physician alongside blood work, imaging and fitness testing. On its own, bought online, it mostly produces a figure to feel good or bad about.
This is how the better longevity programmes use it, as we describe in what a longevity clinic does. LACE arranges full assessments at clinics it has evaluated through bespoke journeys, and physician-led monitoring at home through longevity private services.
よくあるご質問
What is biological age?
Biological age is an estimate of how old your body is in functional terms, based on markers such as DNA methylation or blood values, as opposed to the years since your birth.
How accurate are biological age tests?
They are reasonably accurate across large groups and imprecise for one individual. Repeat tests on the same sample can differ by a year or more, so small changes between tests should not be over-read.
Can you lower your biological age?
Studies show that exercise, diet, sleep and stopping smoking can move the markers in a younger direction. Whether that change translates into a longer life has not yet been demonstrated.
本記事は一般的な情報であり、医学的助言ではありません。診断と治療に関する判断は、資格を有する医師にご相談ください。