Sunlight vs Supplements: Vitamin D, Bone Health & Autoimmunity - with Professor Michael Holick

Vitamin D is one of the most debated topics in health: sunlight vs supplements, safe levels, deficiency risks, and whether it truly impacts conditions beyond bone health.In this conversation with Professor Michael Holick, I explore: • The difference between vitamin D from sunlight vs supplements • Why 40–60 ng/ml (100–150 nmol/L) may be the true “optimal” range • The role of vitamin D in bone health, pregnancy, immunity, and muscle • Why deficiency is linked to preeclampsia, diabetes, and autoimmune disorders • The controversy around guidelines, testing, and “normal” ranges • The evidence for and against megadosing in autoimmune conditions • How sunlight influences health beyond vitamin D (endorphins, nitric oxide, mood) • What Professor Holick himself does daily - from supplementation to training for marathons at age 79Whether you’re a coach or simply someone trying to make sense of vitamin D confusion, this episode will give you clarity from the world’s foremost expert.🎓 Join my 9-Week Science of Thriving Course →⁠ https://scienceofthriving.com.au⁠ 📲 Follow us on Instagram → @tonyboutagy