When does ageing start?

In the field of ageing research, there are different opinions about the onset of the ageing process [Cohen et al. 2020]. Some researchers suggest that ageing begins before birth, as cellular damage can accumulate in parental germ cells or during conception [Kinzina et al. 2019]. On the other hand, others argue that ageing begins at sexual maturity, as the body is no longer under evolutionary pressure to constantly regenerate, and mechanisms that are beneficial early in life may become detrimental later [Gaillard & Lemaître 2017, Williams 1957].
 
Typical signs of ageing, such as wrinkles or a decline in performance, may start to appear around the age of 20 (see "What happens in our bodies as we age?"). However, the rate at which individuals age can vary due to environmental factors and genetic predisposition.

More FAQs on ageing

References:

• Cohen AA, Kennedy BK, Anglas U, Bronikowski AM, Deelen J, Dufour F, Ferbeyre G, Ferrucci L, Franceschi C, Frasca D, Friguet B, Gaudreau P, Gladyshev VN, Gonos ES, Gorbunova V, Gut P, Ivanchenko M, Legault V, Lemaitre JF, Liontis T, . . . Fulop T (2020) Lack of consensus on an aging biology paradigm? A global survey reveals an agreement to disagree, and the need for an interdisciplinary framework. Mech Ageing Dev 191(111316).
• Kinzina ED, Podolskiy DI, Dmitriev SE, Gladyshev VN (2019) Patterns of Aging Biomarkers, Mortality, and Damaging Mutations Illuminate the Beginning of Aging and Causes of Early-Life Mortality. Cell Rep 29(13):4276-4284 e4273.
• Gaillard JM, Lemaitre JF (2017) The Williams' legacy: A critical reappraisal of his nine predictions about the evolution of senescence. Evolution 71(12):2768-2785.
• Williams GC (1957) Pleiotropy, Natural Selection, and the Evolution of Senescence. Evolution 11(4):398-411.