It's really a philosophical question: Would you trade the ability to make certain facial expressions in order to look years younger or at least "well rested"? Maggie, a 52-year-old who wants to be identified only by her first name, would say yes. And so she is sitting in a Manhattan doctor's office having her forehead injected with a dozen or so shots of botulinum toxin A, or Botox, as it is known commercially. The toxin paralyzes local facial muscles and thus eliminates wrinkles caused by muscle contractions--in this case the worry lines in Maggie's forehead.
"The goal is that she won't...