DALLAS, Jul 18, 2011/ FW/ — Alyson Hannigan, star of CBS’ How I Met Your Mother and American Pie was named the official female ambassador of Head & Shoulders, P&G Beauty announced today. Alyson, who joins Head & Shoulders® hair legends including two time Super Bowl champion, Troy Polamalu, and Minnesota Twins All-Star catcher, Joe Mauer, will appear in a fully integrated campaign targeting female consumers beginning this July. “I’m so thrilled to partner with such an iconic beauty brand,” says Alyson. “My hair goes through a lot on-set, but I’ve relied on Head & Shoulders for years to keep