What is biological age?
When asked about age, people usually state their chronological age, i.e. the number of years they have lived. However, chronological age does not say much about the current state of the body: While one person can still run a marathon without any problems at the age of 50, another is already exhausted from climbing the stairs to the first floor. To find out what condition the body is actually in, the biological age can be determined. To do this, various indicators of the human body are analysed, so-called biomarkers. Biomarkers of ageing are characteristics that allow a better prediction of the actual functional state of the organism at an older age and are more reliable than chronological age [Jazwinski, S.M., Kim, S.]. These include, for example, blood pressure, vision, hearing and joint mobility. In addition, the length of the telomeres and certain proteins in the bloodstream are among the measurable biomarkers. Probably the best-known biomarker that can be measured in the blood is cholesterol, but certain inflammation markers are also suitable for determining biological age [Jylhävä, J. et al. ]. Another biomarker that enables the determination of biological age is the epigenetic clock [Horvath, S., Raj, K.]. The values of these biomarkers together give the estimated biological age.
When asked about their age, people usually give their chronological age – the number of years they have lived. However, chronological age does not tell us much about the current state of the body: One person may be able to run a marathon at the age of 50, while another may be exhausted just climbing the stairs to the first floor. To find out what condition the body is actually in, the biological age can be determined. This is done by analysing various indicators in the human body, known as biomarkers. Biomarkers of ageing are characteristics that allow a better prediction of the actual functional state of the organism at an older age and are more reliable than chronological age [Jazwinski & Kim 2019]. These include blood pressure, vision, hearing and joint mobility. Other measurable biomarkers include the length of the telomeres and certain proteins in the bloodstream. Probably the best known biomarker that can be measured in the blood is cholesterol, but certain inflammatory markers are also suitable for determining biological age [Jylhävä et al. 2017]. Another biomarker that can be used to determine biological age is the epigenetic clock [Horvath & Raj 2018]. The values of these biomarkers together give the estimated biological age.
Sources:
- Jazwinski SM, Kim S (2019) Examination of the Dimensions of Biological Age. Front Genet 10(263).
- Jylhava J, Pedersen NL, Hagg S (2017) Biological Age Predictors. EBioMedicine 21(29-36).
- Horvath S, Raj K (2018) DNA methylation-based biomarkers and the epigenetic clock theory of ageing. Nat Rev Genet 19(6):371-384.
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