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.
Blood proteins currently provide the most detailed picture of how quickly you are biologically ageing. An analysis of more than 51,000 people found that 227 out of nearly 3,000 measured proteins were clearly associated with ageing. Five of those proteins appear to play a genuinely causal role, including proteins involved in inflammatory processes and growth regulation. Notably, the largest changes in your protein profile occur around the ages of 41, 60 and 67.
A second way to measure the pace of ageing in blood is through DNA methylation, chemical markings on the genetic material that change as you grow older. The DunedinPACE test, based on such a pattern, predicts disease, disability and death better than older versions of this type of test. People who experienced a great deal of adversity in childhood showed measurably faster ageing. This type of test is for now primarily a research instrument and is not routinely available from a general practitioner.
Routine blood values are also useful, although they are less precise. Four composite scores calculated from around twelve common blood parameters (including inflammatory markers and blood lipids) proved sensitive to lifestyle, particularly diet. A higher inflammatory marker in the blood and a less favourable lipid profile were associated with accelerated biological ageing. In a Chinese cohort study, an elevated biological age based on this type of blood value predicted a 20% higher mortality risk per additional year of biological ageing.
Telomere length, the length of the protective caps on your chromosomes, is a well-known ageing marker in blood. Shorter telomeres indicate greater biological ageing. The effect has been clearly demonstrated in humans, but the measure is less precise than protein profiles or epigenetic clocks and has not been quantified in absolute terms in the available studies.
Long-term obesity from childhood onwards leaves visible traces in the blood: in young adults with an average age of 29 who had been obese for a long time, the inflammatory marker hs-CRP was two to two-and-a-half times higher than in people with a healthy weight. These are large effects for such a young age group, and the researchers link this to accelerated biological ageing at an early age.
Based on multiple large cohort studies (up to 51,904 participants) and validated research instruments. The blood protein findings are partly supported by Mendelian randomisation. Epigenetic clocks and protein profiles are not yet standard clinical tests. Telomere length findings are qualitative and have not been quantified in the available sources.