Sickening migraines would leave defender Pallister sometimes unable to train for two days during his career.
From around the age of 17, he would occasionally have tingling down his arms and suffer crippling headaches which would blur his vison.
"I would probably get three to four migraines a year, and they were quite debilitating, you know - vision, speech, the tingling and the violent headaches. It would be like that for hours, until eventually I would throw up, and that would be the start of the release of the pain," said the ex-Manchester United and Middlesbrough player.
"The following day would leave me absolutely washed out. Two days you were out of the game - the pain, the sickness, the feeling afterwards was awful.
"You kind of wondered being a centre-half and having to head lot of footballs whether that was anything to do with the cause of it. It wasn't until I actually stopped playing football that the migraines kind of disappeared."
Pallister, 59, remembers being accidentally punched in the head by a goalkeeper when competing for a header and ending up in hospital with concussion, despite his manager wanting him to play on.
"I think at this moment I'm OK, I can do my sudokus, try to do a little bit of brain training," said the former defender, who won the Premier League four times with Manchester United.
"But it is enough to know what I did go through with the migraines and the concussions and being knocked out, that the potential is there for me to have brain damage."