ZOE Science & Nutrition

ZOE

The world’s top scientists explain the latest health, nutrition, and gut health research and translate it into practical advice to improve your health & weight. Join ZOE Science & Nutrition, on a journey of scientific discovery. Hosted by Jonathan Wolf.

  1. 1 DAY AGO

    HRV vs. VO2 max vs. ECG: Which wearable metric ACTUALLY matters? | Prof. Malcolm Findlay

    Is your smartwatch just a fun gadget, or a serious medical device?  In this episode, Jonathan Wolf is joined by Dr. Malcolm Findlay, a leading consultant cardiologist, to explore the powerful health data available on your wrist. They decode the most misunderstood metric, Heart Rate Variability (HRV), and reveal how your wearable can provide clinical-grade insights into your heart's health. Dr. Findlay explains the counter-intuitive science behind HRV — why more ‘wobble’ in your heartbeat is a sign of good health — and breaks down the two opposing nervous systems that control it. He shares the latest on how these devices can accurately detect serious conditions like atrial fibrillation and why he, as a cardiologist, trusts the ECG function on a consumer smartwatch to make diagnoses. For listeners who track their own data, this episode is a practical guide to what your numbers actually mean. Dr. Findlay explains how to interpret your personal HRV trends, what constitutes a significant change, and when you should use the ECG feature. He also debunks common myths about heart rate zones, revealing the level of exercise intensity that truly benefits your long-term health. The episode concludes with an empowering look at how this technology is shifting control into our own hands. Can a simple alert from your watch really help prevent a catastrophic event like a stroke? Discover which metrics matter most and how to use them to guide your wellness journey. 🥑 Make smarter food choices. Become a member at zoe.com 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. Timecodes  00:06 Quick-fire questions on heart health 01:45 What is heart rate variability (HRV)? 03:05 Is a steady heart rate a healthy sign? 05:15 Atrial fibrillation makes HRV an invalid measure 07:30 What controls our heart rate? 10:00 Your heart is much more than a pump 11:10 Your thoughts can directly affect your heart 13:45 What lifestyle factors influence your HRV score? 15:15 How does stress impact your HRV? 17:15 Your watch's ECG is a clinical-grade tool 20:20 Wearables can help diagnose serious heart conditions 23:45 Are expensive wearables more accurate? 26:20 Does diet impact your HRV score? 29:15 How to track your HRV score correctly 30:00 Don't panic about small HRV fluctuations 32:30 When to use your watch's ECG function 34:10 The truth about heart rate training zones 36:50 The minimum exercise for a healthy heart 37:40 Does sleep consistency matter? 39:50 What is VO2 max and does it matter? 41:10 Stop comparing your health data to others 41:50 Key takeaways from the episode 📚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 Studies referenced for today's episode Heart rate variability: standards of measurement, physiological interpretation and clinical use, 1996, European Heart Journal Diagnostic Accuracy of a Smartwatch App for the Detection of Atrial Fibrillation, 2019, The New England Journal of Medicine The Effects of Alcohol on Heart Rate Variability and Heart Rate, 2017, The American Journal of Cardiology The relationship between mental stress and heart rate variability, 2007, Journal of Psychosomatic Research Have feedback or a topic you'd like us to cover? Let us know here. Episode transcripts are available here.

    47 min
  2. 25 SEPT

    Fix your sleep with the Royal Marine's sleep consultant Dr. Sophie Bostock

    We’ve all been there: tossing and turning, checking the clock, and stressing about not getting enough sleep. But what if the secret to a good night’s rest isn’t in a pill or a product, but in changing your mindset and daily habits? In this episode, we’re joined by Dr. Sophie Bostock, a leading sleep scientist and founder of The Sleep Scientist. Sophie has dedicated her career to helping people understand the science of sleep and how to build lasting, healthy habits. We dive into what really happens when we don’t get enough sleep, from the psychological effects on our willpower and relationships to the physiological impacts on our long-term health. Sophie debunks common myths about blue light, alcohol, and cheese, and explains the critical difference between occasional poor sleep and true insomnia. And introduces us to Cognitive Behavioral Therapy for Insomnia (CBT-I), explaining why it’s a more effective long-term solution than sleeping pills. Finally, we walk through the simple, science-backed habits you can adopt right now to improve your sleep, starting the moment you wake up. Unlock the science of sleep 👉  ⁠Get the ZOE app  🌱 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. 00:00 How to fix your sleep: what works and what doesn't 01:05 How a lack of sleep affects your willpower and mood 02:02 The evolutionary link between sleep deprivation and a threat response 04:26 How a lack of sleep can impact cognitive function 05:05 Is there a real scientific link between poor sleep and disease? 07:21 The surprising link between sleep and mental health 08:23 Why you can't try to have a good night's sleep 09:33 How to apply the "perfect is the enemy of good" rule to sleep 10:43 The number one reason for insomnia 11:12 The split between those who don't sleep enough and those who worry about it too much 12:12 Why are so many people dissatisfied with their sleep today? 13:00 Why technology is the biggest threat to our sleep 15:46 Why phones are making sleep harder 17:45 The science behind forest bathing 18:55 Can cognitive behavioral therapy help you sleep? 21:10 The surprising clinical definition of insomnia 21:40 Does alcohol help you fall asleep? 26:15 Are sleeping pills a good solution? 29:35 Can exercise help you get better sleep? 32:40 Can eating turkey help you get to sleep? 36:55 What about supplements like melatonin and magnesium? 41:38 What is good sleep hygiene? 44:18 The number one rule for your smartphone and your bedroom 45:32 How can wearables that track sleep help you? 47:34 The technique that will help you fall back to sleep 📚Books by our ZOE Scientists The Food For Life Cookbook | https://amzn.to/4amfIMX Every Body Should Know This by Dr Federica Amati | https://amzn.to/4blJsLg Food For Life by Prof. Tim Spector | https://amzn.to/4amZinu Free resources from ZOE: Live Healthier: Top 10 Tips From ZOE Science & Nutrition |  https://zoe.com/freeguide Gut Guide - For a Healthier Microbiome in Weeks | https://zoe.com/gutguide

    57 min
  3. 18 SEPT

    3 gut bacteria that protect your heart–and what to feed them | Prof. Tim Spector & Prof Nicola Segata

    There's an unseen world inside you, teeming with trillions of tiny inhabitants. Just like any ecosystem, some bugs inside your gut microbiome are beneficial, while others wreak havoc, quietly disrupting your health. What if these disruptive "invasive species" are silently driving the rise of cardiometabolic diseases, the leading cause of illness and death in Western countries? This episode reveals groundbreaking new ZOE research, soon to be published in Nature, that maps this hidden world. We’re joined by Professor Nicola Segata, the study’s co-author and a pioneer of this new technology, alongside ZOE's scientific Co-Founder, Professor Tim Spector, one of the world's top 100 most-cited scientists. Together, they reveal the top-ranked gut bacteria – both good and bad – that influence your health. Discover three powerful "good bugs" and how feeding them can suppress the "bad," transforming your gut ecosystem and paving the way for better health and potential therapeutic breakthroughs. Learn actionable tips for boosting your beneficial bacteria, starving the detrimental ones, and why gut testing is forever changed. 🥑 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 00:00 Introduction  01:05 The most common misconception about gut health 04:04 Your gut bacteria are like mini pharmacists 08:12 Why your gut microbes are as unique as your DNA 14:23 How ZOE is revolutionising health with a new research model 19:39 Groundbreaking research that featured in Nature  22:21 The new, simpler way to measure your gut health 24:25 Meet newly discovered good bugs 28:06 The microbe that thrives when you eat nuts and seeds 32:40 Why only eating kale won't make you healthy 34:25 The 'ancient' gut bug discovered in mummies (and one of our scientists!) 36:37 The future of probiotics 39:17 The shocking truth about store-bought probiotics 42:17 What makes a 'bad' bug bad for your health? 43:45 Could your gut microbes be making you crave junk food? 46:29 The diet your bad bugs love the most 49:10 The future of personalised nutrition for your gut 52:22 How to 'pivot your ' to feed your good bugs 53:55 Is it okay to eat occasionally? 55:53 Tim Spector's simple 'fridge raid ferment'  📚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 Gut microbiome species indicative of cardiometabolic health are modulated by diet in large and interventional cohorts of over 34,000 individuals, forthcoming in Nature, (2025) Gut microbiome species indicative of cardiometabolic health are modulated by diet in large and interventional cohorts of over 34,000 individuals, Published in Nature Microbiology (2025) [3] Research progress of gut microbiota and obesity caused by high-fat diet, Published in Fronteirs in Cellular and Infection Microbiology (2023) Have feedback or a topic you'd like us to cover? Let us know here.Episode transcripts are available here.

    1h 8m
  4. 11 SEPT

    5 threats to your immune system–and how to fight them | Prof. Daniel Davis MBE

    Many supplements claim to “boost” your immune system. Now, we all want to avoid getting sick during the winter months, but do any of these products really work? And is trying to “boost” your immune system even a good idea? Jonathan speaks with Professor Daniel M. Davis, MBE — a leading expert on immunology and Head of Life Sciences at Imperial College London. Daniel has published 145 scientific papers, authored four best-selling science books, and spent 25 years researching how our immune system works. He even helped discover the immune synapse, a breakthrough that changed our understanding of immunity. Daniel explains how your immune system really works, why it’s connected to mental health, and how it can even detect cancer cells. He also clears up common myths and shares what genuinely helps keep your immune system strong through the winter months — and what won’t make a difference. By the end of the episode, you’ll know the practical, science-backed steps you can take to reduce your risk of colds and flu this winter without wasting money on products that don’t deliver. Unwrap the truth about your food 👉 ⁠Get the ZOE app  🌱 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 00:00 Your body’s surprising, built-in cancer defense 02:07 What is the immune system? 03:55 Why ‘boosting’ your immune system can be dangerous 05:28 Are allergies a sign of an overactive immune system? 07:53 The 'hygiene hypothesis': Does being too clean make us sick? 11:05 The unintended global experiment of the COVID pandemic 12:40 How your immune system is constantly fighting cancer 14:20 The revolutionary new therapies that unleash your immune system on cancer 16:05 Is your immune system killing cancerous cells right now? 17:12 Your immune system is the most unique thing about you 19:25 Why you shouldn't blame yourself for getting sick 21:18 The myth of vitamin C and the Nobel prize winner who started it 23:55 The truth about vitamin C and colds 25:06 Does being cold actually give you a cold? 26:15 The powerful link between your immune health and mental health 28:06 Cytokines: The secret messengers you’re going to hear more about 29:00 Could inflammation predict teenage depression? 33:40 What is inflammation, really? 40:33 The double-edged sword of personal health data 42:06 Are there any immune supplements that actually work? 43:35 The one thing that directly harms your immune health 45:05 Why 'fight or flight' is bad for your immune system 47:08 How much exercise is best for your immune system? 48:16 The two most practical pieces of advice for a healthy immune system 📚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 SpectorFree resources from ZOE Live Healthier: Top 10 Tips From ZOE Science & Nutrition Gut Guide - For a Healthier Microbiome in Weeks  Have feedback or a topic you'd like us to cover? Let us know here.Episode transcripts are available here.

    52 min

About

The world’s top scientists explain the latest health, nutrition, and gut health research and translate it into practical advice to improve your health & weight. Join ZOE Science & Nutrition, on a journey of scientific discovery. Hosted by Jonathan Wolf.

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