This extended episode of What's Up Docs? features Chris and Xand van Tulleken's full live conversation with Professor Devi Sridhar at Hay Festival.

Going deeper than the main episode, they explore the tension between individual responsibility and structural change, and why asking "how do I stay healthy?" might be the wrong question altogether. Devi draws on her work across governments and health systems worldwide to examine what genuinely moves the needle on population health. Chris and Xand also ask how Devi's work shapes the way she lives, and what single policy change she'd make tomorrow if she could.

If you’d like to share your thoughts on this or any other topic covered on the podcast, you email us at [email protected] or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Devi Sridhar Producer: Maia Miller-Lewis Executive Producer: Rami Tzabar Editor: Jo Rowntree Researcher: Grace Revill Tech Lead: Reuben Huxtable Video Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4.

Welcome to What's Up Docs?, the podcast where doctors and identical twins Chris and Xand van Tulleken explore the ideas shaping our health and wellbeing.

In this episode, recorded live at Hay Festival, they're joined by Professor Devi Sridhar, Chair of Global Public Health at the University of Edinburgh, to ask how we can live longer, healthier lives.

They dig into the difference between life expectancy and healthy life expectancy, and why the latter is falling in places like the UK. Devi unpacks the biggest factors that shape how well we age, from diet and exercise to mental health and the environments we live in, and shares what decades of working across countries and health systems has taught her.

They challenge the idea that health is simply a matter of individual choice, exploring how the society you're born into can shape your chances of a long and healthy life more than any supplement or wellness hack.

If you want to get in touch, you can email us at [email protected] or WhatsApp us on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Devi Sridhar Producer: Maia Miller-Lewis Executive Producer: Rami Tzabar Editor: Jo Rowntree Researcher: Grace Revill Tech Lead: Reuben Huxtable Video Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC:

Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4.

Chris and Xand van Tulleken continue their conversation about friendship with Dr Tiffany Watt Smith, writer and culture historian.

Tiffany became interested in researching friendships after a moment of crisis in her own friendships. Together, Chris, Xand and Tiffany discuss the difference between male and female friendships and how that has changed over time. They explore the idea that we are living through a friendship recession and what that means for our social connections. And they look at digital friendships and their importance.

If you’d like to share your thoughts on this or any other topic covered on the podcast, you email us at [email protected] or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Dr Tiffany Watt Smith Producer: Faye Lyons-White Executive Producer: Rami Tzabar Editor: Jo Rowntree Researcher: Faye Lyons-White Tech Lead: Reuben Huxtable Visual Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Olga Reed

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4

Welcome to What’s Up Docs?, the podcast where identical twin doctors Chris and Xand van Tulleken cut through the confusion around every aspect of our health and wellbeing.

In this episode, the Docs take a look at the impact our friendships have on our physical health. Why different friendship styles are important and how we can maintain and nurture our social connections.

Joining them is Dr Tiffany Watt Smith, a writer and cultural historian interested in the histories of emotion and medicine.

If you want to get in touch, you can email us at [email protected] or WhatsApp us on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Tiffany Watt Smith Producer and researcher: Faye Lyons-White Executive Producer: Rami Tzabar Tech Lead: Reuben Huxtable Visual Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Ruth Rainey

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4

Chris and Xand van Tulleken take a deeper dive into male contraception with Professor Richard Anderson.

They explore why, despite decades of research, new male contraceptive options are still limited. From funding gaps to shifting attitudes, they unpack the social and scientific barriers that have shaped progress so far.

They also look at how people feel about the idea of male contraception, whether those attitudes are changing, and what it could mean for relationships if new options become available.

Along the way, they tackle common misconceptions and consider what the future of shared contraceptive responsibility might look like.

If you’d like to share your thoughts on this or any other topic covered on the podcast, you email us at [email protected] or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Richard Anderson Producer: Maia Miller-Lewis Executive Producer: Rami Tzabar Editor: Jo Rowntree Researcher: Grace Revill Tech Lead: Reuben Huxtable Visual Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4.

Welcome to What’s Up Docs?, the podcast where doctors and identical twins Chris and Xand van Tulleken explore the ideas shaping our health and wellbeing.

In this episode, they turn their attention to male contraception. We’ve been hearing about a “male pill” for decades, so why don’t we have one yet? They break down how male fertility works, what options currently exist, and the different approaches scientists are exploring, from hormonal gels to non-hormonal treatments.

They also look at the challenges behind developing new contraceptives, from the biology to the strict safety standards and lack of funding that have slowed progress.

To help them unpack it all, they’re joined by Professor Richard Anderson, Professor of Clinical Reproductive Science at the University of Edinburgh. If you want to get in touch, you can email us at [email protected] or WhatsApp us on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Richard Anderson Producer: Maia Miller-Lewis Executive Producer: Rami Tzabar Editor: Jo Rowntree Researcher: Grace Revill Tech Lead: Reuben Huxtable Visual Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4

Chris and Xand continue their conversation about the lymphatic system with Professor Kristiana Gordon, a Consultant in Dermatology and Lymphovascular Medicine.

The docs ask about the growing field of lymphoedema research and how our understanding of the lymphatic system has developed in recent years. They also explore primary lymphoedema, a condition caused by genetic errors that can affect children and young people, and ask what advances in understanding its underlying causes might mean for the development of new treatments.

If you’d like to share your thoughts on this or any other topic covered on the podcast, you email us at [email protected] or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Kristiana Gordon Producer: Claire Justin Executive Producer: Rami Tzabar Researcher: Samara Linton Tech Lead: Reuben Huxtable Visual Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Olga Reed

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4.

Welcome to What’s Up Docs?, the podcast where identical twin doctors Chris and Xand van Tulleken cut through the confusion around every aspect of our health and wellbeing.

In this episode, Chris and Xand explore the lymphatic system, from its vital everyday functions supporting fluid balance and immunity to its more mysterious roles. They look at what happens when things go wrong, examine popular wellness claims around draining and detoxing our lymphatic system, and find out what actually supports good lymphatic health.

Joining them to discuss this is Professor Kristiana Gordon, a Consultant in Dermatology and Lymphovascular Medicine. She’s Clinical Lead at the National Lymphoedema Clinic at City St George's, University of London, and is also a certified lymphoedema therapist.

If you want to get in touch, you can email us at [email protected] or WhatsApp us on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Kristiana Gordon Producer: Claire Justin Executive Producer: Rami Tzabar Researcher: Samara Linton Tech Lead: Reuben Huxtable Visual Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Olga Reed

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4

In this Doctors' Notes episode of What’s Up Docs?, Chris and Xand van Tulleken take a deeper dive into hay fever with Professor Stephen Till.

The docs and their guest explore whether hay fever is really becoming more common, and if so, why. From climate change and air pollution to changes in our environment and biodiversity, they unpack the factors that may be making symptoms worse. They also look at how hay fever varies around the world, including why treatments like allergy injections are more widely used in some countries than others. Along the way, they tackle common myths and share practical advice for managing hay fever more effectively.

If you’d like to share your thoughts on this or any other topic covered on the podcast, you email us at [email protected] or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researcher: Grace Revill Tech Lead: Reuben Huxtable Social Media: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4.

Welcome to What’s Up Docs?, the podcast where doctors and identical twins Chris and Xand van Tulleken explore the ideas shaping our health and wellbeing.

In this episode, they turn their attention to hay fever. What is it, why do so many of us get it, and is it getting worse? They break down what’s happening in the body, how to tell it apart from a cold, and why timing matters when it comes to treatment. They also explore what actually works to manage symptoms, and what doesn’t.

To help them get to the root of it, they’re joined by Stephen Till, Professor of Allergy at Guy's and St Thomas' Hospitals and King's College London.

If you want to get in touch, you can email us at [email protected] or WhatsApp us on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Producer: Maia Miller-Lewis Executive Producer: Rami Tzabar Editor: Jo Rowntree Researcher: Grace Revill Tech Lead: Reuben Huxtable Visual Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4

Chris and Xand continue their conversation about calcium with Dr Sagen Zac-Varghese.

The docs want to know about common issues that are seen around calcium and bone health, especially osteoporosis. They want to learn how osteoporosis relates to calcium, who is at risk and why it is more common in women. They also want to know what inspired Sagen’s passion for calcium and what we can learn from astronauts about bone health.

If you’d like to share your thoughts on this or any other topic covered on the podcast, you email us at [email protected] or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Dr Sagen Zac-Varghese Producer: Maia Miller Lewis Executive Producer: Rami Tzabar Editor: Jo Rowntree Researcher: Mili Ostojic Tech Lead: Reuben Huxtable Video Producer: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

At the BBC: Assistant Commissioner: Greg Smith Commissioning Editor: Rhian Roberts

A Loftus Media production for BBC Radio 4.