"I am literally going to apply this fake tan all over my bikini top," Jemma Violet says, as she smears chocolate brown mousse over her chest, neck and halter-neck bikini. I'm watching a TikTok video ...

Dermatologists have spent years searching for a way to help people tan without the associated health risks. Now, a lab in Boston has created mice that may hold the secret to safe tanning. The mice ...