Every person has two ages: the one on their passport and the biological one. You can read biological age from chemical marks on DNA, which pile up the way rings do in a tree stump. In veterans who lived through war and developed post-traumatic stress disorder (PTSD), those marks show up faster than usual.
Scientists examined 45,091 veterans and compared their biological age with their passport age. In people with PTSD, the cells came out older. What mattered more was not the diagnosis itself but how severe the symptoms were. Those who suffered the most were biologically older by almost two years.
The good news: if trauma accelerates aging, then treatment can slow it down. Help with PTSD is care not only for the mind but for the whole body.
The GrimAge epigenetic clock was trained to predict time to death, so its link to PTSD may reflect a real risk of premature mortality in veterans with this disorder.
In Neal Stephenson's novel Seveneves, psychological stress after a catastrophe leads to accelerated aging in survivors, echoing the idea that trauma affects biological age.
Not published on arXiv. Here are its page, the PDF and the formalization: you can check it yourself, not only read our account.