A new study in the UK will investigate the link between heading a football and developing dementia later in life.
The doctor leading the research claims repeated brain trauma caused the death of former England striker Jeff Astle.
And there are already calls to ban heading from some parts of the game.
Former England and West Brom striker Jeff Astle died from the dementia in 2002.
Many older players have the disease, due to playing when footballs were harder and heavier than those currently used.
It's believed that repeatedly heading the ball can cause concession and brain damage, which shows up later in life.
A research group will be appointed in the next few weeks to study the issue and will reserch whether more ex-professional footballers have degenerative neurocognitive disease, compared to the rest of the population.