In a televised press conference on Monday, Donald Trump and health secretary Robert F Kennedy Jr made a series of unproven claims about autism and its links to paracetamol use in pregnant women, and about childhood vaccinations. The comments were immediately refuted by scientists and health agencies around the world, but many expressed concern about the impact of this misinformation being repeated at the highest levels of government. So what does the science really say? Madeleine Finlay speaks to Guardian science editor Ian Sample to factcheck the claims made in the announcement, and find out what decades of scientific research into autism tells us about its causes and why diagnoses are on the rise. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

A trial is under way to find out if a £100 blood test could transform the way that the NHS diagnoses Alzheimer’s disease. Alzheimer’s is the leading cause of dementia and diagnosis is currently costly and time-consuming. To find out how this blood test could benefit patients, Ian Sample talks to Prof Jonathan Schott, who is co-leading the trial. He explains what the test involves and why it could pave the way for exciting new treatments for the devastating disease. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

The murder of political activist Charlie Kirk has prompted fears about rising levels of political violence in the US after a number of high-profile assassinations and attempted assassinations of political figures in recent years. But how connected are these events and do they signal a rise in public support for this kind of violence? To find out Ian Sample speaks to Sean Westwood, an associate professor in political science at Dartmouth College and director of the Polarization Research Lab. He explains how political violence has evolved and why overestimating the support for such acts can be dangerous. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

At a recent ceremony for world leaders in Beijing, a hot mic picked up a surprising exchange between Vladimir Putin and Xi Jinping about the possibility of living to 150. Putin suggested the secret might lie in repeated organ transplants. But is this the new frontier of anti-ageing research or a fringe and unproven theory? To find out, science editor Ian Sample speaks to Russian affairs reporter Pjotr Sauer and to John S Tregoning, professor of vaccine immunology at Imperial College London and author of Live Forever: A Curious Scientist’s Guide to Wellness, Ageing and Death. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

The fertility rate in England and Wales has fallen for the third year in a row – a trend mirrored across the world, with two-thirds of the global population now living in countries with below-replacement-level fertility. In the second episode of a two-part series, Madeleine Finlay speaks to Dean Spears, assistant professor of economics at the University of Texas at Austin, and Dr Jennifer Sciubba, chief executive of the Population Reference Bureau, to ask whether declining birth rates are really something to worry about – and how societies can adapt to a future with fewer children. Watch the new Guardian documentary Between Moon Tides. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

The fertility rate in England and Wales has fallen for the third year in a row. It is a story that is being repeated all over the world, with two thirds of the global population now living in countries with below replacement level fertility. Low fertility rates have become a talking point on the political right, with Elon Musk claiming that population decline is an existential threat to the future of humanity. But for others, the timescales involved are too vast to start worrying about now. So how should we be thinking about population decline? In episode one of a two-part series, Madeleine Finlay speaks to Dean Spears, assistant professor of economics at the University of Texas at Austin, and to Dr Jennifer Sciubba, president and CEO of the Population Reference Bureau, to find out what has happened to global birth rates, and how governments are trying to tackle the fall. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Psychologists have traditionally believed we become less curious as we age, but recent research has shown that curiosity actually becomes more targeted and specific in our later years. To find out why this happens, and how maintaining broad curiosity into older age can help keep our brains young, Madeleine Finlay hears from Dr Mary Whatley, an assistant professor of psychology at Western Carolina University, and Dr Matthias Gruber, of Cardiff University’s Brain Imaging Centre. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

It’s been a dramatic week at the US Centres for Disease Control and Prevention (CDC). In the space of seven days, the agency’s head was sacked and replaced by an interim head, four senior staff members resigned, and existing staff took to the streets to express support for their ousted leaders. To understand how everything unfolded and what it could mean for the health of Americans, science editor Ian Sample hears from health reporter Melody Schreiber and former CDC director Mandy Cohen. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

There are increasing reports of people experiencing delusions after intensive use of AI chatbots. The phenomenon, dubbed ‘AI psychosis’, has raised concerns that features built into large language models may contribute to some users losing touch with reality. Madeleine Finlay speaks to Dr Hamilton Morrin, a psychiatrist and researcher at King’s College London, about his recent preprint exploring who is at risk and how models could be made safer. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

For more than a decade, scientists have been puzzling over what was causing billions of starfish to dissolve into piles of white goo. Sea star wasting disease has ravaged starfish populations, wiping out 90% of the once common sunflower sea star. Now, researchers have finally identified the culprit. Madeleine Finlay speaks to Dr Melanie Prentice, one of the team to crack the case. She explains the impact the disease has had on the marine environment, how they found the pathogen responsible, and what it means for sea stars’ recovery. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Scientists have found the first robust evidence that people’s genes affect their chances of developing myalgic encephalomyelitis or chronic fatigue syndrome (ME/CFS), a mysterious and debilitating illness that has been neglected and dismissed for decades by many in the medical community. To find out more, Madeleine Finlay speaks to science editor Ian Sample and to Nicky Proctor, who has ME and took part in the research. She also hears from Beth Pollack, a research scientist at the Massachusetts Institute of Technology who studies ME/CFS and related conditions, about how scientific understanding of the illness has improved and how scientists are transforming this knowledge into ideas about future treatments. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

After three years of negotiating, talks over a global plastics treaty came to an end in Geneva last week with no agreement in place. So why has it been so difficult to get countries to agree to cut plastic production? Madeleine Finlay hears from Karen McVeigh, a senior reporter for Guardian Seascapes, about a particularly damaging form of plastic pollution causing devastation off the coast of Kerala, and where we go now that countries have failed to reach a deal. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Europe is suffering from another heatwave as deadly temperatures of up to 44C hit the continent and wildfires blazed across the Mediterranean. To find out why Europe is heating faster than anywhere else, Madeleine Finlay speaks to the Guardian’s Europe environment correspondent, Ajit Niranjan, and to Adam Taylor, professor of anatomy at Lancaster University, to find out how we can try to stay cool as the temperature rises. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

For many of us, slathering on sunscreen to protect our skin in the summer months is a no-brainer. But recently social media has been awash with influencers airing their concerns about the potential dangers of this seemingly innocuous product. So is there anything to the claims that sunscreen is toxic? To find out, Madeleine Finlay is joined by the Guardian’s science editor, Ian Sample. He explains where the science stands on the safety of sunscreen and what we can do to protect our skin all year round. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

It’s a mystery that has long puzzled researchers. Freud called the phenomenon infantile amnesia, and for many years scientists have wondered whether it’s a result of failure to create memories or just a failure to retrieve them. In this episode from March 2025, Ian Sample speaks to Nick Turk-Browne, a professor of psychology at Yale University, whose research appears to point to an answer. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Recently, a group of world-leading scientists called for a halt on research to create ‘mirror life’ microbes amid concerns that the synthetic organisms would present an ‘unprecedented risk’ to life on Earth. Ian Sample tells Madeleine Finlay about why this work initially seemed exciting for scientists and what the risks of it continuing could be. Kate Adamala, assistant professor of genetics, cell biology and development at the University of Minnesota, describes what made her change her mind about pursuing her own research on mirror cells. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

In this episode from January 2025, Ian Sample speaks to Keon West, a professor of social psychology at the University of London, whose new book explores what science can reveal about racism, the inventive methods scientists have used to study it and the scientifically proven ways of tackling racism and discrimination. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

In 2024, the Oxford English Dictionary announced its word of the year was ‘brain rot’. The term relates to the supposedly negative effects of consuming social media content, but it struck a chord more widely with many who feel they don’t have the mental capacity they once had. Gloria Mark, a professor of informatics at the University of California, Irvine, has been studying our waning attention spans for 20 years. In this episode from January 2025, she tells Madeleine Finlay why she believes our powers of concentration are not beyond rescue, and reveals her top tips for finding focus. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Scientists are beginning to understand that ageing is not a simply linear process. Instead, recent research appears to show that we age in three accelerated bursts; at about 40, 60 and 80 years old. To find out what might be going on, Ian Sample hears from Prof Michael Snyder, the director of the Center for Genomics and Personalised Medicine at Stanford University School of Medicine, who explains what the drivers of these bursts of ageing could be, and how they might be counteracted. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Doctors in the UK have announced the birth of eight healthy babies after performing a groundbreaking procedure that creates IVF embryos with DNA from three people. Ian Sample tells Madeleine Finlay about the life-threatening genetic disorders that the technique appears to prevent, and Prof Sir Doug Turnbull describes the 25-year journey to achieving the breakthrough. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>