Every morning for the past year, while her coffee brewed and her breakfast cooked, Libby Brodie has poured a glass of water, mixed in a hefty scoop of collagen powder, and downed it in one. “It’s probably the only thing I do for my skin,” says Brodie, 42, whose skincare routine otherwise consists of “cleaning my face with a bit of hand wash at night and using some moisturizer in the mornings.”

Her powdered supplement, which costs $42 a month for 40 servings, contains “bovine hydrolyzed collagen,” a protein derived from cows. The benefits, according to the manufacturers, include boosted growth for skin, hair and nails, improved joint mobility and “menopause support.” She is unsure if the powder is helping her skin or not, “though people do say I look ten years younger than I am. But what I have noticed is that my hair has gotten much thicker.”