This research was conducted to explore how children’s environments shape their biological development and future life chances. While genes are fixed, the way they are expressed can change depending on experiences such as family background, schooling, or adversity. Epigenetic “clocks” have become the main tool for measuring biological aging, but with multiple versions available, researchers lacked a clear, reliable measure. This paper develops a new combined measure – the Multi EpiGenetic Age (MEGA) clock – and applies it to study how early-life experiences affect life chances.
The paper shows that: 1) the MEGA clock provides a more accurate and consistent measure of biological age than existing individual clocks; 2) teenagers with faster biological aging have lower educational attainment, worse mental health, and worse labour market outcomes in young adulthood; 3) exposure to child maltreatment before age 10 is linked to faster biological aging in adolescence, equivalent to about half a year; and 4) children who start school one year later show accelerated biological aging by age seven, especially those from disadvantaged families.
Policies aimed at improving children’s environments can have lasting biological as well as social and economic benefits. Protecting children from maltreatment and ensuring early access to structured educational settings may help reduce inequalities in health and human capital.