"You know, I don't want to get into things that happened in my past, certainly medical history and so forth," Brady said. "I don't really think that's anybody's business. So, you know, what happened last year, I'm just focused on this year and improving and working on things I need to get better at. So that's how I approach everything.
"I mean I'm not sitting here worried about last year or five years ago. There's other people that do worry about that: my wife or my parents or my sisters or people that love me and care about me. But I do the best I can do to come out and be prepared to play and mentally and physically and I'll give the game everything I can."
Brady was on the injury report last season for thigh, knee and ankle injuries, but was not listed with a concussion.
The quarterback said he's aware of recent research on the effects of permanent brain damage caused by concussions.
"I think you're not blind to it as a player," Brady said. "That's why I believe in so much being proactive with your health. I think when you're a player and you see other players before you that did things a certain way and what's transpired with their health and well-being and you learn from it.
"But it's a contact sport and I think we all understand that. And there's a lot of great benefits that football brings you. You certainly can be put in harm's way. So just do the best you can do as a player. And obviously, it's great that there is more awareness for those types of things. It's been a very important topic, certainly. But just try to be proactive and take care of your body as best way you can."
After turning 40 years old Thursday, Brady is not thinking about life after football.
"I've never thought about not playing," the five-time Super Bowl champ said. "So at least until my mid-forties, I'd say that's a pretty good goal in and of itself. We'll see when I get there. It's been so fun."