Annika Zude, a 16-year-old in the Quad Cities region of Iowa, is one of those teenagers. She is a fan of figures like Andrew Huberman, the brother-sister duo Calley and Casey Means and the conservative commentator Candace Owens.
“Of course, I’m up-to-date with R.F.K.’s posts,” she said.
Ms. Zude’s father, Brad Zude, is a health influencer who runs the Instagram account @healthydadbrad. And last year, Ms. Zude decided to start her own health account on TikTok,
@thatcrunchygirlannika — inspired, she said, by how bad ultra-processed foods made her feel. She has since racked up almost 40,000 followers with videos of herself walking through grocery stores, critiquing popular snacks and personal care products.