What does your klotho level tell you about how fast you are ageing?
A low klotho level is associated with a higher risk of death in older age, but as a personal measure of ageing speed the test is not yet reliable enough to act on.
Blood klotho levels decline as you get older, and that pattern has been found in blood, cerebrospinal fluid and urine. In an Italian study of people aged 65 and over, those with the lowest klotho levels (below 575 pg/mL) had an almost twofold higher risk of dying within six years compared with those with the highest levels (above 763 pg/mL), even after adjusting for age, sex and kidney function. That is a striking association, but it is not proof that low klotho itself causes earlier death.
The strongest evidence comes from animal research. Mice lacking the klotho gene age extremely rapidly and die early. Mice with extra klotho live roughly 30% longer than normal. This suggests that klotho plays a genuine role in the ageing process, but whether that relationship is equally strong and direct in humans has not yet been demonstrated.
As a personal 'ageing clock', a klotho measurement is not yet reliable. Your klotho level is also influenced by how well your kidneys are functioning, your phosphate balance and certain bone diseases. There are no validated reference values for the general population, which means that a single measurement cannot tell you how fast you personally are ageing.
Researchers are working on ways to raise klotho levels, through injections of the protein, synthetic variants, or indirectly via diet and gut bacteria. Results are mixed and have largely not yet been confirmed in humans. No approved treatments are available.
The evidence rests on several pillars: robust animal research (mice with and without the klotho gene), multiple studies in humans tracking klotho levels over time, and one large study involving more than 800 Italian adults aged 65 and over. The animal results are strong and causal; the human findings are associations that do not prove a cause-and-effect relationship. Researchers themselves acknowledge that no validated reference values yet exist for use as an individual biomarker.
Which blood markers can tell you how fast you are biologically ageing?
Blood markers such as protein profiles, DNA-tag patterns, telomere length and standard inflammation markers each offer their own indication of how fast you are biologically ageing. The specialised tests are not yet routine GP care, but your standard blood work already contains useful clues.
What does your VO2max say about how fast you are ageing?
A higher VO2max is strongly associated with lower mortality and a more favourable biological age, but is more of a gauge of your lifestyle than an independent switch for longevity. Reducing body fat and moving more, including gently, delivers the greatest health benefit.
Does your body age faster after a prolonged period of stress?
Prolonged stress is associated with signs of faster cellular ageing, but whether this is truly causal and applies to everyone has not yet been proven. If you want to limit the biological consequences of stress, it pays to pay attention to how you personally experience and process stressful situations.
Does stress make you age faster?
Prolonged stress measurably accelerates your biological ageing. Healthy habits can noticeably slow that process.
Does excess weight accelerate ageing?
Excess weight demonstrably accelerates biological ageing, both through shorter telomeres and through epigenetic clocks. The clearest evidence is already visible in young adults, and losing weight appears to be able to partly reverse the process.
Does everyone age at the same rate?
People demonstrably age at different rates, and after the age of sixty those differences only grow larger. Inherited traits, lifestyle, sex, and environment together determine the pace.