Is the peptide craze backed by science? (opens in new tab)

Cassandra Willyard in Nature: Peptides have become the latest cure-all trend on social media — a way to eliminate wrinkles, build lean muscle, boost metabolism, clear brain fog, heal torn ligaments and more. Influencers rave about their peptide-fuelled glow-ups on TikTok. Bodybuilders exchange information about their favourite combinations at the gym. US health secretary Robert F. Kennedy…