Kevin Towers was hanging by the batting cage before a spring training game when David Wells sidled up. “Shoot, dude,” Wells told his general manager, “I just got diagnosed with Type 2 diabetes.”

Shoot, dude, is right. The Padres had signed the portly lefty to shore up their rotation, and his future — already a question mark because of his age and injury history — had become even more uncertain. Type 2 diabetes, considered less serious than insulin-dependent Type 1, typically is not a debilitating illness as long as one follows the proper program. This program means little fast food and no fast living. This program means exercise and rest. This program means a healthy lifestyle.

For Wells, this program has meant a major change in the way he lives. Wells has been one of the game’s best starting pitchers over the past 20 years, but he is better known for his big belly, beer drinking and brawling. Wells is a guy who has bragged about pitching a perfect game with a hangover, so for him, cutting out all-nighters would seem about as likely as a trip to Vegas without gambling.

Well, close the casinos. Wells is meeting the challenge. He admits to an occasional glass of wine and jumping off his diet now and then, but diabetes has not derailed him. Subsisting largely on chicken and vegetables, Wells says he has lost 12 pounds since the early-March diagnosis and feels better than he has in years. Not that he ever has considered his weight much of an issue.

“I’ve won 20 games at 270, and I’ve won 19 at 220, so as long as I’m somewhere in between, I can get guys out,” Wells says.

Wells may have spent much of his 20-plus years in the majors acting like an overgrown kid, but he grasps the danger of diabetes. He saw his mother die at 58 from diabetes. He realizes his fondness for burgers and booze contributed to his diagnosis. He does not want to risk heart trouble or have to become insulin-dependent, which are possibilities if he can’t control his blood-sugar levels through lifestyle changes. Wells, 44, also wants to pitch until “they drag the jersey off me” and knows his chances of doing that improve if he takes care of himself.

In his starts this season, Wells has been up and down. He was pummeled by the Dodgers so badly that a scout in attendance thought Wells might be done. His next time out, against the Diamondbacks, Wells was so effective — seven innings, three hits, two runs — that same scout rewrote his report.

Wells’ G.M. also was impressed.

“That was as good as he’s pitched as a Padre, even when he was here in ’04,” Towers said.