The National Football League has long been accused of covering up or downplaying the long-term cognitive effects of playing football. But new data released by the league itself shows just how damaging all those years of blows to the head can be. The AP reports that, according to the NFL, “nearly three in 10 former players will develop debilitating brain conditions, and that they will be stricken earlier and at least twice as often as the general population.”

That means we can expect about 6,000 of the 19,000 living ex-players to develop Alzheimer’s or other forms of dementia, while “[d]ozens more will be diagnosed with Lou Gehrig’s or Parkinson’s disease,” both of which have also been associated with playing football professionally.

The disclosure was made as part of ongoing negotiations over a potential $765 million settlement that would cover “thousands of concussion lawsuits,” according to the AP. And while all sorts of sub-controversies have bubbled up as lawyers for the league and former players hammer out the details of the deal, seeing numbers like this come from the NFL will only solidify an increasingly obvious fact: Professional football is very hazardous to players’ long-term health.