The Method - Health in the Real World

Ever woken up exactly one minute before your alarm? Or landed on the other side of the world with a very accurate sense of what time it is back home? Our bodies have fine-tuned internal clocks that set the pace for our circadian rhythm. But why did we evolve to work like this? And what happens to our health when we’re out of sync?

This week, as a follow up from our conversation with Kathryn Pinkham, Greg and Charlie sit down with Dr. Russell Foster, for a crash course on circadian biology.

Russell is a Professor of Circadian Neuroscience at the University of Oxford, Head of the Department of Ophthalmology, and a leading voice on how our internal clocks work. Russell was instrumental in discovering a previously unknown light-sensing system in the eye that helps regulate our circadian rhythms. He is also the author of Life Time: The New Science of the Body Clock. 

In our science section, Russell explains what the biological clock is and why we evolved to have one. He walks us through how our clocks are reset each day by time cues - and why light is chief amongst them. Russell also discusses the concept of chronotypes: why some of us are larks while others are owls, and why that difference is biological, not simply a lifestyle choice. We also delve into why our modern environments can put us out of sync. 

In the practice segment, Russell, Greg, and Charlie get into what we can do to readjust our clocks, or better work with our natural day-night rhythm. We talk about:

• What night owls can actually do when they’re forced into a 9-5 world - and how light and exercise can help (22:06)
• Why seeking bright light the moment you wake up is not a good tip for early birds (24:30)
• What shift workers can do to support their clocks despite inconsistent schedules (26:19)

Finally, we turn to your listener questions in the experience section. Russell shares his own technique for falling back asleep in the middle of the night (a hint: it involves BBC Radio 4), explains why sleep tends to get harder as we age and whether that’s reversible. Charlie and Russell also get into a healthy debate about whether snoring partners should be banished to the spare room, and we take a deep dive into delayed sleep phase disorder, which involves answering Greg’s life conundrums – but not just.

Ultimately, Russell shows us that when it comes to our sleep-wake cycle, different isn't necessarily bad. Tune in to find out what your biological clock is trying to tell you.

If you’d like to send us your health questions for future episodes, remember to email us a voice note or write in at [email protected].

Links:

• Russell Foster - Life Time: The New Science of the Body Clock
• Russell Foster - University of Oxford profile
• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website 
  
  

About Thriva:

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we’re living – and healthspan – how well we’re living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body – and what to do about it – before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions.

To learn more about Thriva’s values and services, visit thriva.co.

Most of us have had a bad night’s sleep. But when insomnia becomes chronic, a whole new world of lifestyle advice seems to open up – one that is confusing, and sometimes fails to fix the problem.

So this week, Greg and Charlie take a deep dive into chronic insomnia with a new guest: Kathryn Pinkham. 

Kathryn is the founder of The Insomnia Clinic and one of the UK’s leading experts in treating chronic insomnia. Kathryn has helped over 5,000 people sleep better using Cognitive Behavioural Therapy for Insomnia (CBT-I) - the NHS-recommended, gold-standard treatment that outperforms sleeping pills for long-term outcomes. Her message: insomnia is very curable, however long or severely someone has been struggling.

Starting with the science, Kathryn walks us through what sleep actually is and how it goes wrong. She explains the two biological systems that drive sleep: the circadian rhythm and sleep drive. She also makes the case for why standard sleep hygiene advice (the dark room, no caffeine after 2pm, a lengthy wind-down routine) often falls short. And yes, it can even add to the problem.

In the practice segment, Kathryn, Greg, and Charlie get into what CBT-I actually involves. Including:

• Why spending less time in bed can cure insomnia and why that works
• How your bed becomes a source of anxiety and how to fix that association 
• What to do when your mind won’t stop racing at bedtime

Finally, in the experience section, we turn to your listener questions. We hear from a parent navigating sleep disruption with a toddler and a newborn on the way, and tackle questions about whether the 8-hour rule is real, and whether deep sleep really matters as much as we’re told.

Enjoy this conversation, and if you’d like to send us your health questions for future episodes, remember to email us a voice note or write in at [email protected]

To Explore Further

• Kathryn Pinkham’s Insomnia Clinic: theinsomniaclinic.co.uk
• Sleep Well, Live Better course: theinsomniaclinic.co.uk/sleep-well-live-better
• Kathryn Pinkham’s Instagram: @theinsomniaclinic  
• Greg Potter’s Website: gregpotterphd.com
• Greg Potter’s Instagram: @gregpotterphd
• Thriva’s Website: thriva.co

About Thriva

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we’re living – and healthspan – how well we’re living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body  – and what to do about it – before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions. To learn more about Thriva’s values and services, visit thriva.co.

The questions have been piling up since our last episodes on weight loss and strength training, so this week, Greg and Charlie are clearing the backlog. We are back for another Q&A episode! 

In the first half of this Greg and Charlie special, we’ll tackle some of the most pressing questions in nutrition and weight management right now. 

• How to navigate weight plateaus after taking drugs like Mounjaro? (2:26)
• What's the difference between intermittent fasting and time-restricted eating; who is it for or not for? (6:31)
• When is it beneficial to try a 24 hour fast? (13:47)

In the second half of this episode, we’ll continue the conversation about longevity, this time through the lens of strength training and nutrition as you age. We get into:

• What you need to do in the gym to build muscle and bone density as you get older (19:26)
• Why what you eat interacts with the muscle you're trying to build (25:23)
• How can osteoporosis best be prevented? (28:19)

And yes, this episode, Greg will do the impossible and answer a question in four seconds flat. What he and Charlie spend the other 40 minutes doing? That is yours to find out.

Episodes mentioned:

• Ep.2 - Resistance Training 101: building muscle for long-term health, with Eric Helms
• Ep.3 - Can astronauts teach us how to age better? With longevity physician Filippo Ongaro
• Ep. 9 - Training and the menstrual cycle: the science of resistance training for women, with Dr. Lauren Colenso-Semple
• Ep. 10 - Debunking cognitive decline: why your brain doesn't have to slow down with age, with Dr. Tommy Wood 
• Ep.11 - Ozempic, Yo-Yo Diets & the Science of Weight Loss, with Dr. David Allison
  
  

Links:

• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website
  
  

About Thriva:

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we're living – and healthspan – how well we're living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body - and what to do about it - before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions. 

To learn more about Thriva’s values and services, visit https://thriva.co/. 

Obesity is one of the most misunderstood and emotionally charged topics in health. But what does the science actually say? Dr. David Allison is one of the world’s leading obesity researchers and biostatisticians. Today, he’s here to cut through the noise.

A professor of paediatrics and director of the USDA Children’s Nutrition Research Centre, David has spent decades challenging assumptions in the field. His rigorous, evidence-led approach is exactly what this conversation calls for.

He sits down with Charlie and Greg to unpack what obesity actually is, what drives it, and how to think about managing it in a way that’s realistic, compassionate, and grounded in evidence.

Starting with the science, David explains why BMI is more nuanced than its critics suggest, and why the conceptual definition of obesity - excess body fat that impairs health or longevity - is harder to work into practice than it sounds. He walks us through what we can say with confidence about obesity’s health risks, the role of energy balance and diet composition, and why body weight tends to creep back up after dieting (with some surprisingly reassuring findings along the way).

In the practice segment, David, Greg, and Charlie get into the practical side of weight management, including:

•        Why higher protein intake is one of the biggest levers for body composition

•        The case for resistance training – especially if you’re using GLP-1 medications

•        How to evaluate diet advice using a simple evidence checklist

•        Why the ‘dental model’ of weight management might change how you think about yo-yo dieting

•        What to know before starting semaglutide or other obesity medications

Finally, in the experience section, we turn to listener questions. We tackle navigating weight management during perimenopause and menopause, how to evaluate conflicting health claims online, and what to do about hair loss while using Mounjaro and GLP-1s.

Enjoy this conversation, and if you’d like to send us your health questions for future episodes, remember to email us a voice note or write in at [email protected].

To explore further

•        David Allison – Website: https://www.linkedin.com/in/david-allison-2917963b/

•        USDA Children’s Nutrition Research Centre: https://www.bcm.edu/research/research-centers/usda-ars-childrens-nutrition-research-center

•        Greg Potter – Website: gregpotterphd.com

•        Greg Potter – Instagram: @gregpotterphd

•        Thriva – Website: thriva.co

About Thriva

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan - how long we’re living - and healthspan - how well we’re living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body - and what to do about it - before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions.

To learn more about Thriva’s values and services, visit https://thriva.co/.

Most of us assume cognitive decline is an inevitable part of getting older. But what if the science says otherwise? Dr. Tommy Wood says this is a modern health myth. His argument: if stimulated in the right way, the adult brain can stay sharp and high-functioning well into retirement age.

A neuroscientist, performance consultant, and recent author of The Stimulated Mind, Tommy has spent his career applying the principles of brain performance to a wide range of lifestyles - from Formula 1 drivers to busy professionals. This week, he sits down with Charlie and Greg, to explore what it actually takes to keep your brain healthy and adaptable across time. 

Starting with the science, Tommy will walk us through how the brain develops, and why being challenged through learning is good for neuroplasticity. He helps us wrap our heads around this with a helpful shorthand he calls “the 3-S Model”: Stimulus, Supply, and Support. Our guest also makes a case for freeing up “headroom”; we’ll let you find out what that means. Together, we’ll explore why cognitive decline is so often the result of a more sedentary lifestyle, and find out how to circumvent that.

In the practice segment, Tommy, Greg, and Charlie will get into tangible exercises and small habits we can all try to improve our brain's ability to learn. Including:

• Why video games are actually good for us (31:30)
• Which physical activity sustains brain health best (35:05)
• The case for learning a language - and yes, this includes coding (38:19)
• How to stay challenged in a world where AI starts doing the thinking for us (40:55)

Finally, in the experience section, we turn to real-life learning challenges and answer your listener questions. We’ve got a fascinating discussion on access to information in the age of the internet, and how that impacts our memory capacity. We also bring you practical answers to reconcile the enjoyment of learning new things with long-term cognitive benefits.

Enjoy this conversation, and if you'd like to send us your health questions for future episodes, remember to email us a voice note or write in at [email protected]

To explore further:

• Tommy Wood - Website
• Tommy Wood - Instagram
• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website
  
  

In the gym, there’s often a pattern: women on the cardio machines, men in the weights section. It's a divide that says a lot about how we think women should train, but how much of that is science, and how much is just habit?

This week, Greg and Charlie sit down with Dr. Lauren Colenso-Semple, a researcher specialising in female physiology and strength training,to answer the question: should women train like men? Lauren is also the co-owner of the MASS Research Review, which helps bridge the gap between cutting-edge research and practical fitness strategies for coaches and trainers.

As always, we’ll start with the science, unpacking the key biological differences between the sexes and what they actually mean for how women should train, their risk of injury, and their relationship with exercise across different life stages. From hormonal fluctuations across the menstrual cycle to the effects of menopause symptoms, we explore how the body changes and what that means for getting the most out of your training. 

From there, we move into the practice, where Lauren, Charlie, and Greg discuss tangible ways to improve our training routines. They discuss:

• How socialisation shapes women's access to sport from an early age (19:08)
• Why resistance training is conducive to healthy aging (26:23) 
•  What should we consider before pursuing Hormone Replacement Therapy? (31:52)

Lauren walks us through what physical training can look like across different life stages, including how contraception and menopause factor into the picture. 

Finally, in the experience section, we turn to your questions. How to get back into training post-partum? Can pilates and stretching help relieve period cramps? Are there exercises we should be prioritising to better manage our cycles? Tune in to find out. 

While we’re here, just a note on language: throughout this episode, we use the term "women" for accessibility, but this episode makes an important distinction between gender and biological sex.

To explore further:

• Lauren Colenso-Semple - Website
• Lauren Colenso-Semple - Instagram
• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website
  
  

If you’d like to send us your health questions for future episodes, you can email us a voice note, or simply write in with your question at [email protected]

About Thriva:

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we're living – and healthspan – how well we're living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body - and what to do about it - before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions. 

To learn more about Thriva’s values and services, visit https://thriva.co/. 

Have you ever written to us and been waiting expectantly for your question to make the cut? Well, it's time we finally answered you. 

This week, Greg and Charlie are back behind the mic for something a little different; a special Q&A episode. Over the course of 8 episodes, we've gathered a number of fascinating listener questions that don't always fit neatly into the subjects we cover. So today, we give four questions the spotlight they deserve, drawing on Greg's depth of knowledge and experience in the world of science.

We cover three big themes: nutrition, caffeine, and sleep. From the basics of fat loss to the science of jet lag, Greg – or Dr. P, as we like to call him – breaks down the science, while Charlie brings the questions you actually want answered, including:

• Low fat or low carb: which is best for weight loss? (3:53)
• Can you lower cholesterol through diet alone, without taking statins? (13:26)
• How does caffeine work, and does it affect everyone's sleep in the same way? (19:07)
• What's the best way to prepare for and recover from jet lag? (And is May a good time to see the cherry blossoms in Japan?) (33:32)

Whether you're fine-tuning your diet, navigating your relationship with coffee, or counting down to a long-haul flight, there's something in this episode for you. And if you stick around, you might just hear from our producer Lise, who may or may not be drinking an alarming amount of French press coffee every morning.

We hope you enjoy this alternative format; and let this be your reminder to send in your questions to [email protected]. Greg's brain is officially on tap.

Links:

• Susanna Holt’s Satiety Index
• Timeshifter App
• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website
  
  

About Thriva:

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we're living – and healthspan – how well we're living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body - and what to do about it - before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions. 

To learn more about Thriva’s values and services, visit https://thriva.co/. 

We all know that eating well matters; but what does that actually mean for you, specifically? Low-fat, low-carb, mediterranean, keto, intermittent fasting… What if the reason no single diet works for everyone is because no single diet should?

In this episode, Greg and Charlie sit down with Dr. Lucia Aronica, an epigenetics and nutrigenomics scientist at Stanford University School of Medicine, who has contributed to the DIETFITS study, one of the best-known trials in the field of personalised nutrition. 

Lucia will break down what factors shape personalisation, and what the research really shows. We discuss the findings of the DIETFITS study, explain how individual responses vary, and break down what variables really matter for a healthy diet. We then zoom out to ask the bigger question: is there actually compelling evidence that a personalised nutrition plan beats a well-designed, healthy, generic one?

From there, we move into our practice segment, where Lucia shares what this all means day-to-day. We cover:

• The healthy eating principles that apply to all of us, whatever our goals (21:41)
• Why testing insulin is crucial (25:06)
• Why pleasure is the key to adopt long-lasting healthy eating habits (29:21)

Finally, in the experience section, we pick up on your questions. From the future of DNA-based nutrition to the truth about keto and your microbiome, meal timing, insulin spikes, and whether that daily tablespoon of olive oil is as good as people say, Lucia gives her take on some of the most common (and most debated) questions in nutrition today.

Personalised nutrition is a genuinely exciting scientific territory, but at times, it can be overhyped. This episode helps you figure out what the evidence actually supports, and what practical steps you can take right now. 

To explore further:

• Lucia Aronica - Website
• Lucia Aronica - Stanford Profile
• Lucia’s Clinical Epinutrition Course
• The Standford DIETFITS Study
• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website
  
  

If you’d like to send us your health questions for future episodes, you can email us a voice note, or simply write in with your question at [email protected]

About Thriva:

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we're living – and healthspan – how well we're living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body - and what to do about it - before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions. 

To learn more about Thriva’s values and services, visit https://thriva.co/. 

We all know what stress is like. The adrenaline on a deadline. Sweaty palms, a racing heart, or a tingling in your fingertips. Sometimes it also feels like a hovering feeling that keeps you stuck at your desk, unable to focus.

So where does stress come from, why does it feel like this, and most importantly, how can we learn to handle it?

In this episode, Greg and Charlie sit down with Professor David Spiegel, psychiatrist at Stanford University and a leading expert on the connection between mind and body, to unpack the science of stress and explore what we can do to manage without medication.

We start by breaking down what stress actually is. David explains the biology behind the “fight or flight” response, how stress can snowball, and why our bodies react to psychological pressures as if they were physical threats. We also explain what hypnosis actually is: a state of focused attention that can help us regulate our response to stress.

From there, we move into our practice segment and David shares simple techniques listeners can try straight away:

• Self-hypnosis tools you can use at home (19:22)
• Breathing exercises like cyclic sighing (22:34)
• How to set up your environment to enhance relaxation (26:40) 

Finally, in the experience section, we hear from listeners navigating stress in their own lives. From questions about supplements and sleep to managing stress in neurodivergence, or getting better at recognising the signs, David offers his guidance on how to take the next step.

While stress is a deeply human thing, we don’t have to suffer from it! With the right tools, we can learn to work with our bodies rather than against them and build resilience to life’s challenges. Listen to this episode to find out how. 

To explore further:

• Reveri App
• David Spiegel - Research
• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website
  
  

If you’d like to send us your health questions for future episodes, you can email us a voice note, or simply write in with your question at [email protected]

About Thriva:

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we're living – and healthspan – how well we're living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body - and what to do about it - before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions. 

To learn more about Thriva’s values and services, visit https://thriva.co/. 

So you want to adopt a proactive approach to health; but do you know what you’re starting from? How do you know what’s normal for you, and what’s worth keeping an eye on over time? For many of us, that first step – baselining our health – can feel confusing, or even intimidating.

In this episode, Greg and Charlie speak to Dr Vishal Shah, Thriva’s Chief Medical Officer, to discuss why establishing a baseline is one of the most important things you can do for your long-term health and show you how to actually do it.

In the science section, Vishal explains why health isn’t just the absence of disease but the result of many interconnected systems working together in the body. We draw connections between physical, mental, and environmental factors, and consider how small changes can lead to wide-ranging benefits.

In the practice section, Greg, Charlie, and Vish discuss how a few well-chosen measures can already paint a useful picture of your health. In a quick-fire round, we explore:

• Why a blood test is an accessible way to check key areas like heart health (ApoB) and hormone levels (26:23)
• What grip strength can show you about long-term vitality (33:16)
• How testing your hearing can protect your cognitive health (36:02)

Alongside more advanced options, we cover where you can access these tests for free or at low cost and how often it makes sense to track.

Finally, we hear from listeners who are already taking steps to track and understand their health. We explore how to find the right balance between proactive tracking and information overload and what alternatives exist for those who find certain metrics stressful, like weighing themselves. Vishal also responds to questions about heart health and nutrition, helping listeners interpret their data and decide the next step in their health journey.

In this episode, we see that small changes can have wide-ranging effects. When it comes to improving healthspan, the first step isn’t doing everything; it’s knowing where you stand.

Resources we mentioned:

• Cognitive health: Food for the Brain Cognitive Test
• Mental well-being: Warwick-Edinburgh Mental Well-being Scale Test
• Sleep: SATED Sleep Questionnaire
• Blood pressure monitors: Omron

To explore further:

• Vishal Shah - LinkedIn
• Greg Potter - Website
• Greg Potter - Instagram
• Thriva - Website
  
  

If you’d like to send us your health questions for future episodes, you can email us a voice note, or simply write in with your question at [email protected]

About Thriva:

Thriva is a proactive health platform built for the modern age. The promise of longevity often comes with years spent in poor health. We want to bridge the gap between lifespan – how long we're living – and healthspan – how well we're living. We combine powerful at-home blood testing with wearable insights and expert guidance. So you can know exactly what’s going on inside your body - and what to do about it - before issues arise. With this podcast, we hope to bring listeners confidence in everyday health decisions. 

To learn more about Thriva’s values and services, visit https://thriva.co/.