Paula Wolfson, wtop.com
WASHINGTON - A football player is constantly taking blows to the head. Most are not strong enough to cause a concussion, but there is growing evidence a series of lesser hits could do significant damage.
Researchers say players who take a lot of these blows tend to leak a certain protein from the brain, and over time the body's immune system starts to fight back.
A research team from the University of Rochester Medical Center and the Cleveland Clinic studied 67 football players from three different college teams.
They found that those that took repeated blows to the head had breaks in the protective blood-brain barrier. As a result, certain substances only found in the brain leaked into the body.
One of those substances is is a protein called S100B, which is usually associated with traumatic brain injury. The researchers say when it leaks into the body, the immune system sees it as a foreign substance, much like a virus.
They say much more study is needed, but stress their research shows repeated sub-concussive blows can be potentially bad not because of the injury itself, but the immune response that may follow.
A group of former NFL greats has been fighting for more study on the impact of repeated blows to the head. Last year, linebacker Junior Seau committed suicide -- an act later linked to a brain disorder thought to be caused by all the hits he took on the playing field.
Follow @WTOP on Twitter.
© 2013 WTOP. All Rights Reserved.
"Sulu" weighs in on the actor filling his shoes in the new "Star Trek."
The Nickelodeon star's antics continue in New York City.
Morgan Freeman can't stay awake during a TV interview. (Video)
A fallen police officer's daughter gets a swarm of support. (Photos)