*The following is excerpted from an online article posted on HealthDay.
Kids who start playing tackle football before age 12 have a higher risk of mental and behavioral problems in adulthood than their counterparts who began playing at older ages, a new study suggests.
Researchers say playing tackle football at a younger age boosted the odds of later problems with behavioral control, apathy, thinking and decision-making by twofold compared to other players.
They also said the risk of clinical depression rose by threefold in these players compared to their counterparts who started playing at older ages.
"These findings were independent of the total number of seasons the participants played football or at what level they played, such as high school, college or professional," said study lead author Michael Alosco, a post-graduate fellow at Boston University's Chronic Traumatic Encephalopathy (CTE) Center.
However, these findings don't confirm that early time on the field actually causes these issues to be more common, only that there's an association between these factors.
Previous research by center found that former NFL players who started playing football before age 12 "had worse memory and mental flexibility as well as structural brain changes on MRI scans compared to former players who began at age 12 or older," Alosco said.
He added that other research has suggested that playing just one season of youth football could change the brain in ways that are detectable via MRI scans.
The new study attempted to track the possible effects of youth football into later life. The cutoff of age 12 "was examined because the brain undergoes key periods of brain development during childhood, and several brain structures and functions reach peak development during the period leading up to age 12 in males," Alosco said.
The study authors asked questions of 214 men who formerly played high school, college or pro football and didn't play other organized sports.
The participants' average age was 51, and 90 percent were white. The men had played various positions except quarterback.
Researchers found that 55 percent of the participants who played football before age 12 showed signs of behavioral problems based on one test compared to 43 percent of those who started later.
In terms of depression, two-thirds of those who started before age 12 showed signs of depression compared to a much lower 44 percent of those who started later.
Researchers adjusted their statistics so they wouldn't be thrown off by high or low numbers of participants who shared certain ages, levels of education, or time spent playing football. They still found a twofold increase in the odds of behavioral and thinking issues and a threefold increase in the odds of depression.
The study has limitations. Almost all participants are white, and it's limited to those who agreed to take part. The researchers don't consider reasons players may have begun playing football early, and it doesn't compare the rates of the various mental problems to similar men who never played football.
The study appears in Translational Psychiatry.