The science of winter depression with Prof. Debra Skene – leading chronobiologist

Try ZOE’s NEW app and gut health test: ZOE.com Winter is almost here! Temperatures are dropping, clouds are descending, and the clocks have changed.  Many of you might be worrying that the Winter Blues are on their way, but perhaps they don’t need to be? Perhaps we can work with our natural, biological rhythms to fend off this blue phase. Today, we’re joined by Prof. Debra Skene, Section Lead of Chronobiology at the University of Surrey and a global authority on circadian rhythms. With over 190 research publications, she’s spent 25 years studying how light and timing affect sleep, mood, and metabolic health. After listening to this episode, you’ll be armed with solid advice that will help you weather winter with a smile, maintaining good health and good mood until the warmth returns. 00:15 The surprising link between your body clock and major diseases 01:25 Quick-fire round: Body clocks, weight gain, and meal timing 03:25 You have a 'master clock' ticking in your brain 10:05 What is 'gut lag'? 11:40 Why light is the most reliable signal for your body (it's not weather) 14:45 Light's 'non-visual' effects: How light affects your mood and performance 16:30 What studies on blind people reveal about our internal clocks 18:50 The shocking health risks of night shift work 21:05 Why you are 'definitely eating at the wrong time' 22:30 The same meal at midnight gives you higher blood fats 25:20 Why living in a cave for a month is 'pretty healthy' 26:20 Are you a 'lark' or an 'owl'? The biology of chronotypes 29:10 What is 'social jet lag' (and why is it linked to weight gain)? 33:05 How winter light changes your body clock 38:30 The direct link between light and 'winter depression' 39:30 Do light boxes actually work for winter depression? 40:40 The discovery of melanopsin: The specific color of light that controls your clock 43:45 Does blue light from your phone really matter for sleep? 45:05 Why light intensity matters more than blue light 48:15 The cheapest and most effective way to get morning light (even in winter) 50:00 Food sets your 'peripheral clocks', but not your master clock 52:20 Why mealtime consistency is the most important rule 53:30 Is daylight saving time bad for our health? 55:35 Summary: Key takeaways for sleep, mood, and eating Have feedback or a topic you'd like us to cover? Let us know here. Episode transcripts are available⁠ here⁠.

Get 6+ FREE breakfast recipes from nutrition experts: https://zoe.com/breakfastguide Why do so many of us eat a "healthy" breakfast like cereal or muesli, only to feel hungry, tired, and foggy by 11 AM? And why is it so hard to break this routine, even when we know it’s not working? In this episode, Jonathan Wolf speaks to Professor Ben Gardner, a leading expert in habit psychology, and Professor Tim Spector, a world-leading scientist in nutrition and gut health.  They explore the science behind why our breakfast routines are broken, how they set us up for a daily blood sugar rollercoaster, and what to do to fix things.  Tim breaks down the latest science on common breakfast foods, explaining why most cereals, muesli, fruit juices, and "high-protein" options are failing us, leading to energy dips and mood changes. Ben explains the psychology of why we're stuck. He reveals why bad habits run on autopilot, why our environment is more powerful than our willpower, and busts the persistent "21-day" myth, explaining how long it really takes to form a new habit. Timecodes: 00:00 Introduction 01:25 Does building a new habit take 21 days? 02:05 Is breakfast the most important meal of the day? 04:05 The 'healthy' breakfast that causes an 11 AM energy dip 05:15 How your breakfast creates a blood sugar rollercoaster 07:15 Can today's breakfast affect tomorrow's hunger? 08:05 The 'healthy' cereal trap: "Only if you're a shareholder of Kellogg's" 10:10 What is a 'habit' in psychology? (It's not what you think) 11:15 The 'autopilot' breakfast: Making food without realizing 13:50 The stale popcorn experiment: Why you eat food you don't even like 16:30 The secret to change: Identify your environmental triggers 18:30 The 'fresh start effect': Why Monday is a powerful day to change 20:40 The "I've already failed today" mindset (and why it's wrong) 22:30 What are 'keystone habits'? 25:45 The 3 ways to break a bad habit (it's not just willpower) 28:00 How to use breakfast as your 'first win' of the day 29:40 Tim Spector's ideal breakfast to avoid a sugar crash 32:30 The 'high protein' cereal lie: "Most of them are rubbish" 33:30 Is Marmite actually healthy? 34:55 Tim's 3 simple principles for a healthy breakfast 38:20 The 21-day myth busted: How long it really takes to form a habit 40:50 What is 'habit stacking'? 41:55 Does missing one day ruin your new habit? 42:35 How to swap your cereal habit (Ben's practical plan) 45:00 How long until a new habit feels 'automatic'? 46:00 A 3-step practical guide to change your breakfast habit

Get your free 5-step plan for hearing loss diagnosis and treatment: click here Hearing loss affects 1 in 5 people globally, increases the risk of developing dementia, and has no cure.  An astonishing half a billion people have hearing loss, which impacts their ability to communicate and connect with others. Hearing loss cases are increasing fast, especially among younger people.  For many, hearing aids and cochlear implants can be life-changing, but they can’t help everyone. But there is hope: Scientists around the world have been working tirelessly to develop NEW treatments for hearing loss.  In this episode, Jonathan speaks to Dr. Marcelo Rivolta, a professor of sensory stem cell biology at Sheffield University.  He’s on the cusp of a major breakthrough that could mean hearing loss becomes a thing of the past.  What you’ll learn: Why hearing loss is becoming more common The shocking link between hearing loss and a 500% increased risk of dementia How modern headphones and loud concerts cause permanent, irreversible damage Why hearing loss can be more isolating than blindness The simple ways you can protect your hearing today How current technologies like hearing aids and cochlear implants work About the groundbreaking new science that could cure deafness using stem cells About Marcelo Rivolta Marcelo Rivolta is a Professor of Sensory Stem Cell Biology at the University of Sheffield. For over two decades, his research has focused on the use of human stem cells for the understanding and treatment of hearing loss. His lab was the first to demonstrate that it was possible to create both auditory hair cells and neurons from stem cells, and his pioneering work is now moving towards clinical trials in humans. Timecodes: 00:00 Introduction  00:26 Does hearing loss only affect older adults? 03:37 Is permanent hearing loss reversible? 06:03 At what volume do headphones start to cause hearing loss? 08:26 Why hearing loss is more isolating than blindness 09:41 The shocking link between hearing loss and dementia 12:00 Can hearing aids reduce your dementia risk? 13:13 How do we hear? A simple explanation 15:15 Why is your microphone just like your ear? 18:07 What goes wrong in your ear to cause hearing loss? 19:20 The cells in your body you’re born with that have to last a lifetime 20:51 Why does loud noise cause irreversible damage? 23:15 Do hearing aids solve hearing loss for everybody? 24:08 The difference between a hearing aid and a cochlear implant 26:20 Is the hearing from a cochlear implant natural? 32:25 Can we find a cure for hearing loss? 34:15 Using stem cells to create new hearing cells 37:32 Can we reverse deafness? Groundbreaking study in animals 38:45 When will a cure for hearing loss be available? 42:25 What is auditory neuropathy? 45:06 What is tinnitus and could this research cure it? 46:46 Top tips to protect your hearing 50:03 Jonathan's summary Information about the Rincell-1 clinical trial, such as patient eligibility and other related aspects, is available at https://www.rinri-therapeutics.com/our-clinical-research/#rincell For further details, please contact [email protected] Episode transcripts are available here: https://zoe.com/learn/category/podcast

🥑 Make smarter food choices. Become a member at http://zoe.com  Have you ever wondered why you can lose weight on a diet, only for it to come back with a vengeance? If you’ve blamed yourself for a lack of willpower, our guest today argues you’ve been misled. The old mantra of “eat less, move more” is failing us, and the key to understanding why lies deep within our biology. In this episode, Jonathan is joined by Dr. Andrew Jenkinson, a bariatric surgeon and author with decades of experience in the science of metabolism. Dr. Jenkinson dismantles the calorie-counting myth and explains the powerful biological system that controls our weight: the "set point." He reveals how our modern diet and lifestyle have broken this system, but also provides a clear, science-backed path to fixing it. Dr. Andrew Jenkinson is a consultant bariatric surgeon and the author of Why We Eat (Too Much): The New Science of Appetite. In this episode, you’ll learn: Why the idea that weight loss is simply about willpower is a damaging myth. The science of the "weight set point" and how your brain fights to keep you at a certain weight. How your metabolism acts like a "dimmer switch," slowing down to prevent weight loss when you diet. The crucial role of hormones like leptin and insulin, and why our modern diet causes "leptin resistance" — the reason your brain can’t tell it’s full. How yo-yo dieting can actually raise your set point, making you heavier in the long run. A practical, step-by-step plan to lower your set point by changing what you eat, not just how much. The truth about new weight-loss drugs like Ozempic and their long-term effects. How managing stress and improving sleep can be as important as your diet for sustainable weight management 🌱 Try our new plant based wholefood supplement - Daily30: https://zoe.com/daily30?utm_medium=zoe_podcast&utm_source=podcast_platform&utm_campaign=d30 *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system Follow ZOE on Instagram |  https://www.instagram.com/zoe/ Timecodes 00:00 Introduction 00:20 Is gaining weight as we age inevitable? 01:38 Why ‘eat less, move more’ is a myth 03:53 Is your weight predetermined by your genes? 06:36 How your mother's experience in the womb can alter your dna 10:35 Why most diets are doomed to fail in the long term 12:16 Your brain has a weight 'set point' it tries to defend 15:27 The 'weight anchor': your body's powerful defence against weight loss 17:22 The reason you often end up heavier after a diet 19:00 A shocking study: yo-yo dieting made mice fatter than a junk food diet 21:35 The 'joker in the pack' controlling 70% of your energy burn 23:12 Your body has a hidden metabolic 'dimmer switch' 27:53 The mystery of the missing calories 32:35 Why dieting can actually raise your weight set point 34:31 The master hormone that tells your brain when you're full 36:08 The hidden reason your brain can't tell you're full 37:35 Why feeling hungry and lazy are symptoms, not causes, of obesity 39:00 The 'broken gas tank meter' analogy for weight gain 41:26 Step 1 for resetting your weight: the 30-day challenge 42:07 Why you need to stop snacking between meals 43:50 What is mindful eating and why does it matter? 46:22 Can time-restricted eating lower your set point? 48:37 The truth about new weight loss drugs like ozempic 50:28 The surprising impact of stress and sleep on your weight 51:42 The single most important thing to understand about weight loss 📚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

Today, we’re talking about plants. For years, our diets have been guided by a simple three word slogan: ‘five a day’. While it’s well established that eating fruit and vegetables is good for us, some experts believe the ‘five a day’ message puts too much emphasis on quantity, and not enough on variety. So, is time to adjust our guiding plant principle? I’m joined by Professor Tim Spector and chef Hugh Fearnley-Whittingstall, who advocate for a new goal: eating 30 different plants each week. Together, we’ll explore why diversity is key for your microbiome and share some delicious ways to bring more plants onto your plate. 🌱 Try our new plant based wholefood supplement - Daily30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system 📚 Books from our ZOE Scientists: The Food For Life Cookbook by Prof. Tim Spector Food For Life by Prof. Tim Spector Every Body Should Know This by Dr Federica Amati Free 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 Listen to the full episode here

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.

If you’re a regular listener of this podcast, you’ll know that our cholesterol level is closely linked to heart health. With that in mind, it’s easy to be drawn to foods labelled as ‘low fat’, ‘reduced fat’ or ‘fat free’ - all of which promise to keep our cholesterol low and heart strong.  However, is it really that simple? I’m joined by Professor Sarah Berry to break down the difference between good and bad cholesterol, bust some myths about low-fat foods, and explain how we can make smarter food choices that support our heart. 🥑 Make smarter food choices. Become a member a zoe.com - 10% off with code PODCAST 🌱 Try our new plant based wholefood supplement - Daily30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system 📚 Books from our ZOE Scientists: The Food For Life Cookbook by Prof. Tim Spector Food For Life by Prof. Tim Spector Every Body Should Know This by Dr Federica Amati Free 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 Listen to the full episode here

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

Today, we’re unwrapping the truth about chocolate. For many of us, chocolate is a guilty pleasure. But what if I told you that you didn’t need to feel guilty? Because it turns out that not all chocolate is created equal. And by changing the type of chocolate you eat, you can support your health instead of harming it. In this episode, I’m joined by chocolate expert Spencer Hyman and Sarah Berry to show you how to enjoy chocolate with a clear conscience. 🌱 Try our new plant based wholefood supplement - Daily30+ *Naturally high in copper which contributes to normal energy yielding metabolism and the normal function of the immune system 📚 Books from our ZOE Scientists: The Food For Life Cookbook by Prof. Tim Spector Food For Life by Prof. Tim Spector Every Body Should Know This by Dr Federica Amati Free 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 Listen to the full episode here

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.