For those of you who haven’t tuned in to MTV lately, the Foo Fighters are not a posse of intergalactic video-game characters. They’re a platinum-selling rock band fronted by ex-Nirvana drummer Dave Grohl, and they’re a record label’s dream: Their first three albums (their latest is There Is Nothing Left to Lose) have sold over a million copies each. Now the garage rockers are throwing their weight behind activists who argue that HIV may not cause AIDS.

Foo Fighter Nate Mendel was hipped to HEAL offshoot Alive and Well’s director Christine Maggiore’s book, What If Everything You Thought You Knew About AIDS Was Wrong?, by a friend. Mendel was so “struck” by the book that he shared it with his bandmates and organized a January 14 benefit for Alive and Well in Hollywood. At the concert, Foo fans not only listened to an opening speech by Maggiore but were handed free copies of her book, which calls HIV harmless and safe sex unnecessary.

But not all fans are sold. When Damian Purdy, 21, of Winnipeg, Manitoba, saw the Alive and Well banner ad on the Foo Fighters’ website, he balked. “They should stick to making good music,” Purdy says, “rather than supporting a message that promotes reckless irresponsibility.”

The risk of distributing such information to young fans isn’t lost on Mendel. “We’re not saying it’s not sensible to use a condom, because there are other reasons to use a condom,” says the earnest bassist, who admits he has no scientific background and knew no people with HIV before he met Maggiore. But Mendel, who’s planning future Alive and Well fundraisers, adds that youth doesn’t necessarily equal foolishness. “People can make this distinction,” he says, “even our younger audience members.”