NFL players 4x neurodegenerative mortality

A new study from Mass General Brigham, Boston University, and the Christopher Nowinski found that National Football League (NFL) players are nearly four times more likely to die from neurodegenerative diseases such as dementia, Parkinson's disease, and ALS compared to the general population. The cohort study of 19,824 NFL players who played between 1960 and 2019 showed lower all-cause mortality but a 3.8-fold increase in dementia mortality and a 3.88-fold increase in Parkinson's mortality. Players with careers of five or more seasons had double the risk of those with shorter careers. The study introduces the STARS effect to explain why NFL players live longer overall despite higher brain disease risk. Additionally, the Christopher Nowinski announced that former Dallas Cowboys player Marshawn Kneeland, who died by suicide at age 24, was diagnosed with CTE. Former United States — Tennessee running back Chris Johnson revealed he was diagnosed with ALS in 2025.