A study of the effects of violence including "domestic violence, frequent bullyingor physical maltreatment by an adult" using twins concluded that the stress causes premature aging.

Children who have experienced violence might really be older than their years. The DNA of 10-year-olds who experienced violence in their young lives has been found to show wear and tear normally associated with aging, a Duke University study has found.

Violence Puts Wear and Tear On Kids' DNA

The findings suggest a mechanism linking cumulative childhood stress to ... accelerated aging, even at a young age.

The author concludes, "Some of the billions of dollars spent on diseases of aging such as diabetes, heart disease and dementia might be better invested in protecting children from harm."