From collagen powders to $100 creams, the skincare industry thrives on promises. However, many of the products we rely on for younger, healthier skin are built on shaky evidence. In this episode, world-renowned dermatologist Professor John McGrath breaks down what’s real and what’s not. We explore how skin truly ages, what happens beneath the surface, and why some popular treatments don’t do what they claim. John dismantles three of the biggest myths in skincare, including the truth about SPF, collagen, and “bio-active” ingredients that never make it past the top layer of your skin. Professor McGrath is a Professor of Molecular Dermatology at King’s College London and editor of the British Journal of Dermatology. His research has transformed how we understand genetic skin disorders and vitamin D’s role in skin health. This conversation is packed with surprising insights - and one daily step that really does support healthier skin as you age. 🥑 Make smarter food choices. Become a member at zoe.com - 10% off with code PODCAST 🌱 Try our new plant based wholefood supplement - Daily 30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system Follow ZOE on Instagram. Timecodes Timecodes 00:00 Can you reverse sunburn in 24 hours? 00:54 The anti-aging skincare routine that actually works 02:21 Is collagen powder a scam? 03:33 Your skin renews itself every 4 weeks 05:11 70 billion microbes live on your skin 07:56 Can gut bugs really reverse hair loss? 09:12 The two ways your skin actually ages 11:03 Why your skin stops repairing itself 13:19 What makes your skin sag as you age 14:55 Can lifestyle really slow down skin aging? 16:15 The enzyme that smoking activates to destroy collagen 17:01 Does vaping wreck your skin too? 18:04 Why expensive creams don’t erase wrinkles 19:21 Why most anti-aging products don’t penetrate your skin 20:41 The skincare label trick: “appearance of wrinkles” 24:03 The white bottle effect: how packaging influences trust 27:55 The double-edged sword of sunlight 30:22 Why sunlight makes you feel amazing 32:53 Could sun exposure actually protect your heart? 35:01 Are we protecting our skin too much? 39:12 The 3 steps of a dermatologist-approved routine 42:05 Are you using enough sunscreen? (Probably not) 44:55 Should you wear SPF in winter? 50:01 The vitamin D3 sunburn recovery hack 52:58 How much is too much vitamin D? 📚Books by our ZOE Scientists The Food For Life Cookbook Every Body Should Know This by Dr Federica Amati Food For Life by Prof. Tim Spector Free resources from ZOE Live Healthier: Top 10 Tips From ZOE Science & Nutrition Gut Guide - For a Healthier Microbiome in Weeks  Mentioned in today's episode Genome-wide association study identifies 143 loci associated with 25 hydroxyvitamin D concentration, Nature Communications (2020) Topical tretinoin for treating photoaging: A systematic review of randomized controlled trials, Int J. Womens Dermatology (2022) Sunlight Has Cardiovascular Benefits Independently of Vitamin D, Blood Purification (2016) Have feedback or a topic you'd like us to cover? Let us know here. Episode transcripts are available here.