Childhood

A new study reveals that

repeated exposure to stress factors in children under three years old could have harmful effects on their mental health in later years.

stress factors such as poverty, family instability and abuse
Previous studies carried out on animals and in humans revealed that

difficulties in early life could have lasting effects on the epigenome, the chemical compounds that alter and control gene function and the expression of DNA.

individuals who had encountered particularly difficult situations in their first years and others.
Poverty had the greatest impact
Stress factors experienced before the age of three had a much greater impact

than those experienced between the ages of three and five, or five and seven, the study revealed.

Exposure to stress was generally associated with increased methylation, causing a reduction in the expression of specific genes.

Living in poorer or run-down areas seemed to have the greatest impact, 

ahead of familial financial stress, sexual or physical abuse and growing up in single-parent families.
“These findings suggest that
the first three years of life may be an especially important period for shaping biological processes
that ultimately give rise to mental health conditions,”

While events experienced in early childhood had the greatest adverse effects, difficult circumstances experienced at a more advanced age are also not without consequence, the scientists noted.
“Our results need to be replicated by other investigators,

and we also need to determine whether these changes in DNA methylation patterns are associated with subsequent mental health problems.

Only then will we be able to really understand the links between childhood adversity, DNA methylation and the risk of mental health problems,”.