Welcome to What’s Up Docs?, the podcast where doctors and identical twins Chris and Xand van Tulleken explore every aspect of our health and wellbeing. In this episode they want to know about testosterone replacement therapy.

It’s been suggested to Xand that he needs some testosterone replacement therapy - but should he take it? Does testosterone really boost mood, sexual appetite and energy? When testosterone declines in men as they get older and when women go through the menopause, can increasing testosterone offer positive results?

Chris and Xand are joined by Dr Channa Jayasena, expert in reproductive endocrinology to find out.

If you’d like to share your thoughts on testosterone or anything else that caught your attention in this episode - you can email us at whatsupdocs@bbc.co.uk or Whatsapp us on 08000 665123.

Presenters: Drs Chris and Xand van Tulleken Guest: Dr Channa Jayasena, Imperial College London Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researchers: Lisa Lipman 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

Chris and Xand dig deeper into the role of testosterone with Dr Channa Jayasena, expert in reproductive endocrinology from Imperial College London.

They discuss how  testosterone interacts with other hormones, particularly oestrogen and the different roles these hormones play when it comes to male and female biology. They also explore the populism of testosterone.

If you’d like to share your thoughts on this, or any other topic in the series, you can email at whatsupdocs@bbc.co.uk or Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Dr Channa Jayasena, Imperial College London Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researchers: Lisa Lipman Tech Lead: Reuben Huxtable Social Media: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

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

A Loftus Media production for BBC Radio 4.

In a new podcast from BBC Radio 4, doctors and identical twins Chris and Xand van Tulleken explore the messy and complicated world of health and wellbeing.

In this episode they want to know about knee pain - why do we get it, what can we do to treat and prevent it, and should we really just ‘push through it’? They talk to Philip Conaghan, Professor of Musculoskeletal Medicine at the University of Leeds, to find out.

If you want to get in touch, you can email at whatsupdocs@bbc.co.uk or WhatsApp us on 08000 665123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Philip Conaghan Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researcher: Grace Revill Tech Lead: Reuben Huxtable Production Manager: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Commissioning Editor: Rhian Roberts A Loftus Media production for BBC Radio 4

Join Chris and Xand for some bonus content, digging deeper into the topic of each week’s episode of What’s Up Docs?

In this episode they look at knees and are joined by Philip Conaghan, Professor of Musculoskeletal Medicine at the University of Leeds. They discuss key exercises we can be doing to help with chronic knee pain, what the best kind of pain relief is, and how to ensure longevity of the ligaments.

If you’d like to share your thoughts on this, or any other topic in the series, you can email at whatsupdocs@bbc.co.uk or send us a message or voice note on Whatsapp on 08000 665 123.

Presenters: Drs Chris and Xand van Tulleken Guest: Philip Conaghan, Professor of Musculoskeletal Medicine at the University of Leeds Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researchers: Grace Revill Tech Lead: Reuben Huxtable Social Media: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Sound Design: Melvin Rickarby

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

A Loftus Media production for BBC Radio 4.

In a new podcast from BBC Radio 4, doctors and identical twins Chris and Xand van Tulleken explore the messy and complicated world of health and wellbeing.

In this episode they want to know about ‘hanger’. Is it real? Or is being hangry just a marketing tool?

Guest Professor of Social Psychology Viren Swami from Anglia Ruskin University says it's real - but hunger is not the only thing that contributes to our emotional state.

If you want to get in touch, you can email at whatsupdocs@bbc.co.uk or WhatsApp us on 08000 665123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Viren Swami Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researcher: Lisa Lipman Tech Lead: Reuben Huxtable Production Manager: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Commissioning Editor: Rhian Roberts A Loftus Media production for BBC Radio 4

Join Chris and Xand for some bonus content, digging deeper into the topic of each week’s episode of What’s Up Docs?

Such is their passion for health and wellbeing that when joined by an expert they find it hard to contain their excitement and the questions just keep coming. Doctors' Notes is the solution. Here, they spend a little more time with the expert and explore some ideas that they can’t get out of their minds.

In this episode, picking up from their conversation with Professor of Social Psychology, Viren Swami, Chris and Xand take a further look at hanger. Looking into the personal, physical and psychological components of hanger, they delve into the political and social issues attached to hunger.

If you’d like to share your thoughts on hanger or anything else that caught your attention in this edition of Doctors' Notes or the main episode on hanger, you can email whatsupdocs@bbc.co.uk or Whatsapp on 08000 665123.

Presenters: Drs Chris and Xand van Tulleken Guest: Professor Viren Swami of Anglia Ruskin University Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researcher: Lisa Lipman Tech Lead: Reuben Huxtable Production Manager: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Commissioning Editor: Rhian Roberts A Loftus Media production for BBC Radio 4

In a new podcast from BBC Radio 4, doctors and identical twins Chris and Xand van Tulleken explore every aspect of our health and wellbeing. In this episode they want to know about willpower. What does it do? Can any of us get better at doing difficult things?

Guest Kimberley Wilson, a chartered psychologist, says it's the biggest question and longest standing issue in psychology and philosophy. Does willpower even exist?

If you want to get in touch with us, you can email at whatsupdocs@bbc.co.uk

And we are also on WhatsApp where you can send a message on 08000 665123

Presenters: Drs Chris and Xand van Tulleken Guest: Kimberley Wilson Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researcher: Lisa Lipman Tech Lead: Reuben Huxtable Composer: Phoebe McFarlane Commissioning Editor: Rhian Roberts A Loftus Media production for BBC Radio 4

Join Chris and Xand for some bonus content as they dig deeper into the topic of each week’s episode of What’s Up Docs?

Such is their passion for health and wellbeing that when joined by an expert they find it hard to contain their excitement and the questions just keep coming. Doctors' Notes is the solution. Here, they spend a little more time with the expert and explore some ideas that they can’t get out of their minds.

In this episode, picking up from their conversation with chartered psychologist Kimberly Wilson, Chris and Xand take a further look at willpower. Xand gets a bit of free therapy, evaluating his own relationship to willpower and they discuss relapse and the role it plays in the cycle of behavioural change.

If you’d like to share your thoughts on willpower or anything else that piqued your interest in this edition of Doctors' Notes or the main episode about willpower, you can email whatsupdocs@bbc.co.uk or Whatsapp on 08000 665123.

Presenters: Drs Chris and Xand van Tulleken Guest: Kimberly Wilson Producer: Jo Rowntree Executive Producer: Rami Tzabar Editor: Kirsten Lass Assistant Producer: Maia Miller-Lewis Researcher: Lisa Lipman Tech Lead: Reuben Huxtable Production Manager: Leon Gower Digital Lead: Richard Berry Composer: Phoebe McFarlane Commissioning Editor: Rhian Roberts A Loftus Media production for BBC Radio 4