Catch up quick: Viral TikTok and YouTube videos from Miami's Scratcher Girls helped propel the niche into the spotlight.

• Using long nails, the Scratcher Girls trace and scratch clients' backs, scalps, arms and legs.

• Similar services are now surfacing across the country.

Zoom in: Alpha Massage & Wellness in Minneapolis has offered a scratch ritual since opening last November, owner Caroline Nyakundi tells Axios.

Yes, but: Only about 3% of her clients choose it, she says.

• A service she added to the menu just two months ago is proving far more popular: the "beat me up" massage.

Between the lines: Scratchers claim their work releases mood-boosting neurotransmitters, but that doesn't mean it's science-backed.

• Although the pleasure of scratching an itch has been studied, "there's no research" proving that other light scratching has benefits, Tiffany Field, a faculty member at the University of Miami who studies massage, tells Axios.
• Field's data shows that moderate-pressure massage, as opposed to light pressure, can lower cortisol, increase serotonin, slow the heart rate and improve sleep.
• That doesn't mean scratching offers no benefits, though. "Psychologically," Field says, it could be "very relaxing, because it's reminiscent of an early childhood pleasurable experience."