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A new study found 99% of NFL players tested, suffered from a degenerative brain disease, caused by concussions.
The research published in the journal JAMA, Tuesday, was the largest ever brain study of its kind.
Families donated the brains of more than 200 former football players to Boston University for testing. In the study, 111 were former NFL players and 110 had Chronic Traumatic Encephalopathy or CTE. The study found 87% of the men who played for an average of 15 years had the disease.
Joining us to discuss this further is Dan Neil, the two time Super Bowl Champion with the Denver Broncos.