60 Minutes recently highlighted a University of North Carolina study of retired NFL players which found a major correlation between concussions and the onset of dementia and depression. This comes on the heels of a recently released National Football League commissioned phone survey of 1,000 retired players, a study which found that compared with the general public, football players under the age of 50 were an astounding 19 times more likely to be diagnosed with dementia, Alzheimer's and other memory related diseases.

Dr. Ann McKee, a neuropathologist at Boston University School of Medicine, has been working on a brand new area of research on the brain that has provided physiological proof of brain disease in athletes who have suffered concussions. She showed a brain sample from Walter Hilgenberg, a former Minnesota Viking who died last year of Lou Gehrig's disease at age 66. His wife donated his brain to research because he had so many severe concussions during his career. Dr. McKee says slides, cross-sections of his brain, show that Hilgenberg was suffering from a devastating, degenerative brain disease, called chronic traumatic encephalopathy, or CTE. It was first seen in boxers and can only be diagnosed after death, when the brain is dissected.

Just this year, Dr. McKee has examined the brains of 16 former athletes, including 11 football players. The results were shocking: they all had the brain disease, CTE. Her research was published in a leading medical journal in the field.

Even more troubling, she says, CTE actually progresses undetected for years, silently eating away at brain cells, until it causes dementia and other cognitive problems.

"It seems to be triggered by trauma that occurs in a person's youth; their teens, their 20s, even their 30s. But it doesn't show up for decades later," she explained. "People think it's a psychological disease or maybe an adjustment reaction, maybe a mid-life sort of crisis type of thing. But actually, they have structural disease. They have brain disease."

Dr. McKee's research found that athletes in any contact sport are at risk of permanent brain damage.

Dr. Cantu, co-author of the UNC study, is even more worried about kids and concussions.

Last year, high school athletes reported having 150,000 concussions. Younger brains are more vulnerable to injury, doctors say, and unlike in the NFL, there's often no one on the sidelines trained to diagnose brain injuries.

That's what happened to Zackary Lystedt in 2006.

At the young age of 13, he suffered the devastating affects of repeated concussions and collapsed on the field and experienced multiple strokes.

Zackary remained in a coma for over a month. Three years later and now 16 years old, he's in a wheelchair and spends at least 40 hours a week in therapy.

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Eric Tyson is the only best-selling personal finance author who has an extensive background as an hourly-based financial advisor and who does not accept speaking fees, endorsement deals or fees of any type from companies in the financial services industry or product or service providers recommended in his articles, books and his publications.