The Claim: Learning sign language can help a baby talk earlier.
The Truth: There's no doubt that learning to sign can help a baby communicate her needs more easily. And the largest study to date, conducted by the mother of the baby-sign movement, Linda Acredolo, PhD, a Parents advisor and professor emeritus of psychology at the University of California, Davis, did find that babies who learned to sign spoke on average three or four months sooner than those who didn't. But there are some skeptics. "When parents are signing to their children, they're also talking to their children," says Dr. Hirsh-Pasek. "They're communicating in two different ways. That's not to say the effect isn't real, but is it just the signing -- or is it a positive effect of the extra attention? We just can't say." Moreover, there's no scientific evidence at all that early talking, walking, or reading translates into long-term success in life.
The Bottom Line: There's no drawback to teaching a baby to sign -- and lots of potential benefits -- so get those hands moving and keep up a steady stream of conversation.