'Informant' Star Matt Damon Blabs About Weight, Kids, Charity

For Matt Damon, this summer has been one of gains and losses.

He's preparing for the birth of his second daughter, helping launch a charity and hoping for some major reductions around his waistline.

Damon, 37, is working overtime to drop the 30 pounds he packed on to play a whistle-blower in Steven Soderbergh's 2009 drama "The Informant". He has to shed the weight by early September to be svelte for re-shoots of the Paul Greengrass drama "Green Zone", in which he plays a soldier looking for weapons of mass destruction in Iraq.

"If you put it on, it's easier to get it back off," he says.

His weight-loss strategy: "I'm just boxing. I figure if you get hit enough times, it will fall off."

The former Sexiest Man Alive jokes that People magazine took back the title. "Now I'm the Sexiest Man Alive's chunky cousin."

Speaking from his Miami home, Damon says that, except for the "Green Zone" reshoots, he's "taking the rest of the year off, and I'm just hanging out with my family."

Wife Luciana is "due soon," and the baby will join Isabella, 2, and Damon's stepdaughter, Alexia, 9. "I'm so outnumbered down here, it's crazy," jokes Damon of his girl-powered household.

The couple haven't yet picked out a name. "We decided to wait till she's born, and then we're going to get a look at her and we'll probably keep debating it," he says.

His other "baby" he's prepping for is the launching of One X One Foundation's U.S. operations, with a San Francisco gala on Oct. 23. The charity, started in Canada, helps children worldwide.

"It's about helping kids," Damon says. "It's not like before I was a father I was like, 'The hell with those kids.' But something does shift when you have a child of your own. It's hard not to look at every child as somehow connected to you."

Damon was inspired by Bono and his ONE campaign to fight poverty. Part of Damon's duties: recruiting talent for events.

"I have to make calls. Sheryl Crow is going to play at one of our events. It's the easiest call in the world to make," Damon says. "I just tell what the charity is about, and everyone wants to do anything they can."