Professor Harry Sumnall is a Professor in Substance Use at the Public Health Institute, Liverpool John Moores University, and a member of the UK Government’s Advisory Council on the Misuse of Drugs (ACMD).

In this conversation we break down the drug policy terms people constantly confuse — and why that confusion matters in real life.

We cover:

• What decriminalization actually means (and what it doesn’t)
• Decriminalization vs depenalization vs legalization
• Why illegal markets create unique harms (potency, adulteration, organized crime)
• The “continuum” approach: prevention → harm reduction → treatment → recovery
• Why education alone rarely changes behaviour — and what does
• Stigma and dehumanization: how they block help-seeking and worsen outcomes
• Why policy is rarely purely “evidence-based” — values and politics always play a role

If you’ve ever heard someone say “decriminalization = legalization,” this episode will fix that.

Professor Pooja Saini is a UK-based academic and practitioner specialising in mental health, suicide prevention, and community-based support, with years of experience working at the intersection of research, healthcare, and real-world services.

In this conversation, we explore why mental health is still so hard to talk about, why people often struggle in silence, and how misunderstanding, stigma, and system design shape the way we respond to distress. Rather than slogans or motivation, this episode focuses on understanding — what actually helps people cope, recover, and feel supported before things reach crisis.

This episode is for anyone who wants to better understand mental health — whether for themselves, for someone they care about, or simply to have more compassionate and informed conversations.

In this episode, we’re joined by Dr Emily Hird, a cognitive neuroscientist and research fellow at University College London’s Institute of Cognitive Neuroscience, whose research focuses on the brain mechanisms underlying depression and other mental health conditions.

Dr Hird’s work examines how changes in reward processing, motivation, and effort-based decision-making contribute to symptoms such as anhedonia and apathy. Her research also explores how dopamine signalling, inflammation, and stress interact in depression — and why physical activity may help by reshaping these brain circuits over time.

Together, we unpack why depression isn’t just a change in mood, why everyday tasks can feel disproportionately effortful, and why exercise can be as effective as antidepressants for some people. Rather than focusing on willpower or “pushing through,” this conversation looks at the neuroscience of effort, small wins, and how understanding the brain can make recovery feel more possible.

Topics covered

• How depression changes brain function
• Anhedonia, apathy, and effort sensitivity
• Dopamine, reward circuits, and motivation
• Inflammation and mental health
• Why exercise helps depression (neuroscience explained)
• Why starting small matters

This episode is for education and discussion, not medical advice. If you’re struggling, consider speaking to a healthcare professional.

Dr Blake Stobie is the Lead Consultant Clinical Psychologist and Director at the Centre for Anxiety Disorders and Trauma (CADAT) in London. With over 25 years of experience treating anxiety, obsessive-compulsive disorder, PTSD and related conditions, Dr Stobie blends deep clinical insight with a warm, evidence-based approach to understanding the mind.

We dive into the surprising truth about intrusive thoughts, what they really tell us about how our mind works, and why nearly everyone experiences them — even if they feel bizarre or upsetting. Dr Stobie reframes these thoughts not as flaws or warnings, but as a normal part of human cognition, and shows how anxiety and rumination can take over when we give too much weight to the stories we tell ourselves.

If you’ve ever felt pulled into a spiral of worry or wondered why your brain seems to “spam” you with distressing ideas, this conversation offers clarity, compassion, and a path toward breaking the loop.

Dr Riccardo De Giorgi, MD, DPhil, MRCPsych, is a Clinical Lecturer in Psychiatry at the University of Oxford and an Honorary Consultant in General Adult Psychiatry at Oxford Health NHS Foundation Trust. He teaches psychiatry and psychopharmacology, leads experimental medicine research, and focuses on repurposing immuno-metabolic drugs — including GLP-1 receptor agonists — for cognitive and mental disorders.

In this episode, we explore GLP-1 receptor agonists (GLP-1RAs) — medications originally developed for diabetes and obesity — and their emerging relevance to psychiatry and brain health. Recent analyses, including work led by Dr De Giorgi, review preclinical and clinical evidence suggesting these drugs may influence cognitive processes, reward pathways, mood regulation, and inflammatory mechanisms implicated in conditions such as depression, addiction, Alzheimer’s disease, and other psychiatric or neurocognitive disorders.

We discuss:

• How GLP-1 signalling works in the body and the brain
• Why psychiatrists are increasingly interested in GLP-1RAs beyond metabolic effects
• The current evidence for psychiatric and cognitive benefits (and limitations)
• Mechanistic challenges in translating animal findings to humans
• The importance of stratifying patients and integrating biomarkers in future research

This episode strips away hype to uncover what science currently supports — and what remains an open question — about the psychiatric potential of GLP-1 receptor agonists.

Professor Luigi Nibali is an award-winning specialist periodontist who has been keeping gums healthy and saving teeth for more than 15 years. He is a Professor of Periodontology at King’s College London (Guy’s Hospital) and a leading clinician–scientist in gum disease and oral inflammation.

Trained in dentistry in Italy, Luigi Nibali completed an MSc and PhD at the UCL Eastman Dental Institute, where his research focused on the genetic and inflammatory drivers of aggressive periodontitis. His work spans clinical periodontology, systemic inflammation, and the links between oral health and cardiovascular disease, diabetes, cancer, and neurodegeneration.

In this episode, we break down what periodontitis actually is, why it often develops silently, and why bleeding gums are an early warning sign that shouldn’t be ignored. We explore how chronic oral inflammation can contribute to whole-body inflammation, including its relationship with markers such as C-reactive protein (CRP).

We then discuss Luigi’s recent feasibility study using a fasting-mimicking diet alongside standard periodontal treatment — what the protocol involved, what they observed, and why diet may help regulate inflammation without adding more medication.

This conversation connects oral health, diet, inflammation, and long-term disease risk, with practical insights on prevention and why gum health remains one of the most overlooked pillars of overall health.

Highlights

• Bleeding gums aren’t normal — they signal chronic inflammation

• Periodontitis often progresses silently for years

• Oral inflammation can increase systemic inflammatory burden (CRP)

• Diet quality may influence gum disease severity

• Fasting-mimicking diets show early promise as an adjunct therapy

Topics Periodontitis • Oral inflammation • Systemic inflammation • CRP Oral microbiome • Fasting-mimicking diets • Diet & inflammation • Prevention & oral hygiene • Lifestyle and metabolic health