CLAIM Reduces up to 95 percent of frizz and curl for 30 days. Nourishing natural oils like avocado and coconut are kind to colored hair ($15; at drugstores).
EXPERT OPINION "This works much like salon straightening treatments," Hammer says, "except the formalde-hyde has been replaced with a kinder chemical that gives you basically the same results but is a lot safer to use."
OUR VERDICT During the 90-minute application and drying process, our eyes got a little red and our bathroom reeked of chemicals. The good news: Afterward, those once-kinky strands felt considerably smoother.Read MoreLess