Darren Woodson and Herm Edwards both agree that the Patriots will comfortably beat the Jets in Week 6. (1:00)

FLORHAM PARK, N.J. -- The old guy at quarterback is defying Father Time, thriving, in part, because of what he calls a "holistic" approach to his job. It's a mind-and-body philosophy that includes a new diet (no carbs) and brain exercises (yes, really). He absolutely believes it's a big reason for his impressive start.

Say hello to the new Josh McCown.

What, you thought we were talking about Tom Brady?

He's doing OK too, but New England's most beloved health nut has been doing it for years -- eating right and winning, that is. For McCown, 38, who faces the 40-year-old Brady on Sunday in the NFL's version of the Grey(beard) Cup, this represents a new lifestyle.

McCown, who has led the New York Jets to a 3-2 start, has made a concerted effort to improve his diet and training regimen. Instead of waiting to rehabilitate bumps and bruises, McCown is proactive, hitting the trainer's room every day for prehab.

At meal time, he stays away from junk food. A typical day: oatmeal for breakfast; chicken breast or salmon and a salad for lunch and dinner. On the side, he enjoys a complex carbohydrate (e.g. sweet potato) and grilled vegetables.

After dedicating himself to a new diet and mental approach this offseason, Josh McCown is off to one of the best starts of his career. Ken Blaze/USA Today Sports

No, he hasn't dabbled with the Brady staple.

"I haven't tried avocado ice cream," McCown said with a laugh.

Except for fast-food stops on the drive from North Carolina to Texas -- he moved his family during the offseason -- the well-traveled quarterback has remained true to his diet. He started thinking about a lifestyle change a few years back while playing for the Chicago Bears, observing Jay Cutler, a diabetic, adhere to an ultrastrict diet. But McCown didn't truly commit until he started preparing for the current season.

Which begs the question: Why did he wait until his 16th professional season?

"My age, understanding how some of these things affect inflammation in your body," McCown told ESPN. "The science continues to grow and points to these things. That's been helpful.

"I'm fortunate enough to have a good metabolism and good genetics, but you can't just down anything. I don't necessarily gain weight if I eat bad, but it's more the inflammation, it's how I feel throughout the day. I wanted to feel better and I wanted my brain to work better."

McCown was so into his personal reinvention that he "did some things mentally to strengthen my brain, which help me in my studies." For starters, he studied the brain, actually doing research on how it works and how to make it work better. As he explained, "I wanted to understand the things you can do to help you achieve optimal performance."

He declined to get into specifics, except to say he used "different exercises and techniques." He also devoted the offseason to studying more game film than ever before, taking a different tack than usual. Instead of breaking down the opponent, the usual drill, he studied the film as if he were playing in the game.

Hey, it's working. A 60 percent career passer, McCown is up to 71.4 percent, ranking second in the NFL. If he beats the Patriots, he'll have four wins as a starter for the first time since 2004, when he went 6-7 for the Arizona Cardinals.

The fitness fanatic from Foxborough has noticed.

"It seems like the team is really rallying around him," Brady said of the Jets and McCown. "They're playing well as a team and he's having a great season. So, yeah, I certainly know having that experience is helpful. When you've seen a lot of things going into as many years as he and I have played together, you know a lot about how to prepare and get ready for opposing defenses. He's doing all the right things."

McCown is a proponent of "the process," as he calls it. He believes every player needs to develop his own process. While his nutritional game plan might not be as hard-core as that of Brady, it's better than what he had.

"Obviously, whatever he's doing is working," McCown said of Brady. "He's got a good routine for himself that has helped him with longevity. I think it's wise. [My approach] is in the same vein as that. What you eat matters and helps you feel better, and it's going to help you perform better."