Australia's favourite science champion Dr Karl Kruszelnicki shares his science-backed principles for optimal health and wellbeing, and how his approach has evolved over the years.   WANT MORE FROM DR KARL? To hear today's full interview, where he discusses how our health interests have changed over the decades...search for Extra Healthy-ish wherever you get your pods. For more on Dr Karl’s new book A Periodic Tale (Harper Collins, $36.99) see here or catch him @doctor_karl, on TikTok here or via his site here.    WANT MORE BODY + SOUL?  Online: Head to bodyandsoul.com.au for your daily digital dose of health and wellness. On social: Via Instagram at @bodyandsoul_au or Facebook. Or, TikTok here. Got an idea for an episode? DM host Felicity Harley on Instagram @felicityharley.  In print: Each Sunday, grab Body+Soul inside The Sunday Telegraph (NSW), the Sunday Herald Sun (Victoria), The Sunday Mail (Queensland), Sunday Mail (SA) and Sunday Tasmanian (Tasmania).  See omnystudio.com/listener for privacy information.