Less is more.

Trout pouts, aka fish lips, once were so ubiquitous, they got an entry in the Oxford Dictionary: "The result of aggressive augmentation of the lips with filler." Another definition: totally 1990s. "I remember the moment when patients stopped asking for bigger lips in the mid-2000s," says dermatologist Peter Kopelson. "Jocelyn Wildenstein scared the fish lips off everyone!"

Fish lips might be extinct, but in Hollywood, maintaining a youthful mouth is hotter than ever. There simply are more effective and conservative ways to do it.

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Plastic surgeon Lawrence Koplin maintains that lip enhancement counters the effects of aging, which include a receding upper lip and tiny lines above the mouth. He also arguably launched trout-pout mania in the late '80s: "Barbara Hershey came to me when shooting Beaches, and we gave her fuller lips by injecting collagen. But she didn't tell me her character would wear red lipstick!" Hershey became a media train wreck for her supposed vanity, and such actresses as Melanie Griffith and Meg Ryan donned career-inhibiting trout pouts.

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"Fillers don't move," says Koplin, "but fat transfer doesn't make the lips stiff. Now we under-correct for a natural look. We lace a bit into the vermilion border for a little more fullness." His other new, more restrained method involves injecting two drops of Botox above the lip line on each side: "It relaxes the muscles so they can roll out without making them bigger."

Dermatologist Harold Lancer is credited with ending the trend. "I tried to bring attention to how silly they looked," he says. "Fillers with hyaluronic acid can be reversed, but Radiesse, Sculptra and silicone can't. After hearing about permanent damage, the public lost their demand."

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These days, instruments for injecting are more sophisticated. "We put in a tiny cannula, which leaves a small thread of filler, a fraction of previous volumes," says Lancer. "Now directors and stylists are warning actresses not to get too altered." Adds Kopelson: "Thank God we're living in more tasteful times. Extreme anything looks wrong, unless you're Rihanna."

This story first appeared in the Jan. 17 issue of The Hollywood Reporter magazine.