Can you tell someone's biological age from their face?
Your face does emit biological signals, but it is too limited and too variable to measure your biological age accurately. Take facial ageing seriously as a possible indicator, but do not rely on it as a measure of your health.
Facial ageing does reveal something about biological age, but it is only one piece of a larger puzzle. People aged 60 and over who felt they looked older than their peers had a 61% higher chance of developing dementia in the years that followed, according to a large British study with more than 195,000 participants. That association held up even after adjusting for known risk factors such as a genetic predisposition to Alzheimer's disease. This is a correlation, however, not a proven causal relationship.
Specific wrinkles, such as crow's feet, were linked to cognitive decline in a smaller Chinese study of 612 people. The quarter with the most crow's feet had more than twice the rate of cognitive impairment compared with the quarter with the fewest. However, that study measured everything at a single point in time and had a small group of participants, so caution is warranted here.
The face is therefore not a reliable thermometer for your overall biological age. Large-scale organ research shows that different organs and systems each have their own pace of ageing. Facial features are one signal among many, alongside blood markers, immune function, gut microbiota and more. Chronological age alone is already a poor measure of biological ageing, and a single facial feature is even more so.
The eyes are perhaps the most informative part of the face. Cataracts and macular degeneration (damage to the central field of vision) are direct expressions of ageing in the eye. Interestingly, these eye diseases share biological mechanisms with Alzheimer's disease, Parkinson's disease and cardiovascular disease. In this way, the eye offers a kind of window onto how the body ages as a whole.
Genetic research further suggests that facial ageing is partly determined by biology and heredity, through genes in immune cells that also influence other ageing traits. What this means in practical terms for, say, a blood test or lifestyle advice is not yet clear. Oral health, including tooth enamel, gums and salivary glands, also provides age-related signals, but is an incomplete measure: smoking accelerates it considerably, and severe gum disease is a disease rather than ordinary ageing.
Claims are based on PMID 39506848 (large prospective UK Biobank study and smaller Chinese cross-sectional study), PMID 35263580 (multi-omics organ ageing), PMID 40659289 (genetic-immunological study, Mendelian randomisation), PMID 27501493 (oral ageing), PMID 38977082 (eye ageing), PMID 40110678 (immune function and biological age).
How can I measure my biological age?
Epigenetic clocks, in particular GrimAge and PhenoAge, currently offer the best estimate of your biological age, but they are not yet ready for straightforward home use and require expert interpretation.
Can an epigenetic age test really tell you how old your body is?
An epigenetic age test provides a meaningful indication of biological ageing, but is not yet a definitive verdict on your health. Use the result as a starting point for a conversation with your doctor, not as a fixed judgement.
Can a blood test show how old your organs are?
Blood tests can provide an estimate of biological ageing and flag the risk of specific conditions, but they cannot yet directly measure organ age. If you want to track your biological clock, DNA methylation and blood chemistry scores are the best-studied options -- but use them as a guide, not a diagnosis.
How large can the difference between my chronological age and my biological age be?
The typical spread between your biological and calendar age is around one to two years. Studies mention no hard upper limit, but biological age does predict health risks better than your year of birth.
Which blood values tell you something about how quickly you are biologically ageing?
Blood values such as protein profiles, DNA methylation patterns, telomere length and common inflammatory markers each provide an indication, in their own way, of how quickly you are biologically ageing. The specialised tests are not yet standard general practice care, but your routine blood work already contains useful clues.
Does your biological age change differently at night than during the day?
The night is biologically not a pause but an active recovery phase, and that phase deteriorates noticeably with age. Those who protect their sleep rhythm, with fixed times, limited screen use before bedtime and a longer nightly eating break, preserve that recovery function for longer.