Is it?

https://www.tmslab.org/publications/835.pdf

From Boston University’s CTE Center: It surveyed 214 former football players and found that playing before age 12 was linked to worse behavioral regulation, depression, apathy and executive function, plus higher odds of clinical depression and apathy. The early starters had about twice the risk of problems with behavioral regulation, apathy and executive functioning, and three times the risk of elevated depression scores. That held regardless of how many years they played, how many concussions they reported, or whether they reached high school, college or pro level.