What if boosting your immune system is the wrong goal?  Today, Dr Giulia Enders explains how boosting immunity may increase inflammation and why your symptoms are often part of your body’s defence. Your immune system is not failing when you feel sick. It is trying to protect you. So what should you focus on instead? That’s the idea at the very heart of Giulia’s new book, Organ Speak. Giulia is a gastroenterologist and author whose previous book, Gut, sold eight million copies and helped convince the world that gut health was worth taking seriously. She explains how the immune system really works and why symptoms like a runny nose, cough, or fever come from your body, not the infection itself. You’ll learn how sugar may push the immune system toward inflammation, how stress can weaken it, and why sleep is key for producing immune cells. This episode also explores how exercise helps regulate your immune response. The core idea is simple: health is not about making your immune system stronger. It is about keeping it balanced. By the end of this episode, you will have practical ways to support that balance and habits to help your immune system respond in the right way. If the sneezing, runny nose, fever - all of it - are actually the whole point, how much energy should you spend in suppressing them? 🌱 Try our science-backed and tasty wholefood supplement Daily30 Get our brand-new app and Gut Health Test designed by world-leading gut health and nutrition scientists to build healthy eating habits 👉 Join ZOE Follow ZOE on Instagram. Timecodes 00:00 Intro 02:45 Why being sick feels like failure 04:30 The problem with only treating the gut 07:16 Why your body is not broken 10:25 When your immune system gets overprotective 13:28 The virus may not cause your symptoms 15:36 Should you stop cold symptoms? 16:40 When diarrhoea medicine can backfire 18:05 Should you take painkillers when sick? 18:52 Why immunity is not a war 20:46 The invisible microbe cloak protecting you 22:49 How your body clears bacteria from skin 24:10 Your microbiome is part of immunity 26:58 Is your immune system like AI? 28:00 Why boosting immunity can go wrong 30:36 Are immune supplements worth taking? 31:45 How stress weakens your gut barrier 34:25 The one-minute breathing reset 37:48 Why sleep builds immune cells 39:27 The most important half of sleep 44:16 Do naps help your immune system? 46:40 What to eat for immune balance 48:00 How exercise moves immune cells 49:10 Why exercise when sick can be risky 54:26 Strength vs cardio for immunity 56:00 The immune system takeaway everyone needs 📚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 Ferment by Prof. Tim Spector Good Mood Food (preorder) by Prof. Tim Spector Free resources from ZOE The Hormone Harmony Guide: Tuning Your Body’s Internal Orchestra Eating for Better Brain Health: Your brain-gut blueprint How to eat in 2026 - Discover ZOE’s 8 nutrition principles for long-term health Live Healthier: Top 10 Tips From ZOE Science & Nutrition Gut Guide - For a Healthier Microbiome in Weeks  Better Breakfast Guide Mentioned in today's episode Organ Speak: What it really means to listen to our bodies by Giulia Enders Gut by Giulia Enders Association of Stress-Related Disorders With Autoimmune Disease, JAMA (2018) Sugar-sweetened soda consumption and risk of developing rheumatoid arthritis, AJCN (2014) Have feedback or a topic you'd like us to cover? Let us know here. Episode transcripts are available here.