Shocking Study: CTE Found in 40% of Young Athletes' Brains

February 13, 2025

A groundbreaking study has revealed alarming rates of chronic traumatic encephalopathy (CTE) in young athletes, raising serious concerns about the long-term effects of contact sports on brain health.

Key Findings

Researchers found brain abnormalities associated with CTE, such as thalamic notch (top left) and degradation of the fornix (top right), in brain bank samples from young athletes who played contact sports and died before age 30. The bottom images are of a control brain. McKee lab, Boston University CTE Center

  • Over 40% of brain donors under 30 showed signs of CTE

  • Most cases were mild (stages 1 or 2 out of 4)

  • Majority of affected athletes played only at amateur level

  • Football players with longer careers more likely to have CTE

What is CTE?

CTE is a progressive brain disease caused by repetitive head impacts. It leads to brain damage similar to Alzheimer's and has been found in people as young as 17.

The Study

Researchers examined 152 donated brains from athletes under 30 who had a history of repetitive head impacts. They also surveyed next of kin about symptoms.

Brain Abnormalities

The study found several structural differences in CTE-affected brains, including:

  • Thalamic notch

  • Degradation of the fornix

  • More immune cells (macrophages) around blood vessels

Symptoms and Causes

Common symptoms reported included:

  • Depression

  • Apathy

  • Impulsivity

  • Impaired decision-making

Importantly, these symptoms were present in athletes with and without CTE, suggesting multiple factors may be at play.

What This Means for Young Athletes

Dr. Ann McKee, the study's lead researcher, emphasizes: "This study clearly shows that the pathology of CTE starts early." The high rate of CTE in young athletes is particularly concerning. While the study doesn't prove that all contact sports lead to CTE, it raises important questions about the safety of these activities for young people. Parents, coaches, and athletes should be aware of the potential risks and consider ways to reduce head impacts in sports. Remember, this study looked at donated brains, which may not represent all young athletes. More research is needed to fully understand the relationship between repetitive head impacts, CTE, and symptoms in the general population.