While it may be easy to blame our genes for the way we look, our physical and mental health, new research emphasizes that life experiences influence the way we live and manage what life throws at us.
“In this time of emphasis on genes for this and that trait, it is important to remember that our environmental experiences also make important contributions to who we are as people,” said principal investigator Kenneth Kendler, M.D.
“When I was growing up, in talking about the importance of a good diet, we used to say ‘You are what you eat.’ What this study shows is that to a substantial degree, ‘you are what you have experienced.’ That is, your life history stays with you in impacting on your background book, for good or for ill,” he said.
Kendler and an international team of researchers from VCU and other universities analyzed nine data sets of more than 12,000 identical twins with symptoms of depression and/or anxiety through the lifespan.
By studying identical twins, researchers have a pair of individuals who are born with identical genetic makeup and a shared family environment.
Their environments may begin to change as they begin to make divergent decisions as they get older that come with lifestyle, diet or friends.
Participants completed reports relating to their own symptoms of anxiety and depression in a five-to-six-year period. The participants varied in age and were from American and European population-based registries.
According to Kendler, statistical models were used to observe how components of individual variation changed over time.
The team observed that as the twins moved from childhood into late adult life, their respective presentation of anxiety or depression became individualized and then stabilized in their later years.
Researchers noted that environmental experiences contributed substantially to inter-individual differences in levels of anxiety and depression by mid-life in adults.
The study is found online in the journal Psychological Science and will be soon published in hard copy.