Science Weekly

Kevin Hall spent 21 years at the US National Institutes of Health and became known globally for his pioneering work on ultra-processed foods. In April he unexpectedly took early retirement, citing censorship under the Trump administration. Now he has co-authored a book with the journalist Julia Belluz that aims to bust myths and challenge wellness orthodoxy on everything from weight loss and metabolism to supplements and wearables. Hall tells Ian Sample what he wants us all to understand about diet, exercise and weight loss, and what led to his departure from the job he loved. Help support our independent journalism at theguardian.com/sciencepod

The renowned primatologist Jane Goodall has died aged 91. She will be remembered for her observations that revolutionised our understanding of chimpanzees, as well as her tireless environmental advocacy. Ian Sample talks to the Guardian’s global environment editor Jon Watts, who met Goodall many times, to find out what her scientific legacy will be. Help support our independent journalism at theguardian.com/sciencepod

Scientists are warning that academic publishing needs urgent reform in order to retain trust in the research system. Ian Sample tells Madeleine Finlay what has gone so wrong, and Dr Mark Hanson of the University of Exeter proposes some potential solutions. Help support our independent journalism at theguardian.com/sciencepod

The Ig Nobel prizes were awarded recently – for science that makes you laugh and then think – and the peace prize was given to a cheeky study testing the link between alcohol and language proficiency. Does a drink really help us to converse more convincingly in another tongue, or does it just give us inflated confidence? To find out, Madeleine Finlay speaks to a member of the winning team, Dr Fritz Renner, a researcher in clinical psychology and psychotherapy at the University of Freiburg in Germany. Help support our independent journalism at theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 theguardian.com/sciencepod

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 professor Michael Snyder, director of the Center for Genomics and Personalised Medicine at Stanford University School of Medicine. Michael explains what the drivers of these bursts of ageing could be, and how they might be counteracted.. Help support our independent journalism at theguardian.com/sciencepod

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 theguardian.com/sciencepod

Madeleine Finlay is joined by Ian Sample to discuss three intriguing science and environment stories. From a breakthrough in the quest to create organs in the lab to a world-first climate visa that will see citizens relocate from the island of Tuvalu to Australia, plus what happens when two massive black holes collide. Help support our independent journalism at theguardian.com/sciencepod

Guardian feature writer Rhiannon Lucy Cosslett recently wrote about the growing cohort of parents whose children are on the waiting list for an autism or ADHD diagnosis, and are turning to the internet to buy melatonin to help them sleep. She tells Madeleine Finlay about their experiences and what is driving them to the hidden market. Paul Gringras, a consultant in paediatric sleep medicine and neurodisability, and lead of sleep medicine at King’s College London, also explains why melatonin can be helpful for neurodivergent children and why he is concerned about the increasing number of parents looking for it online. Help support our independent journalism at theguardian.com/sciencepod

In the days since the deadly floods in the Texas Hill Country, speculation has grown about whether cuts to US weather agencies may have contributed to the the number of casualties. Ian Sample talks to the meteorologist and climate journalist Eric Holthaus to find out whether this narrative stacks up and what the consequences could be for extreme weather prediction in the future. Help support our independent journalism at theguardian.com/sciencepod

The actor recently posted a photo of himself undergoing a £10,000 procedure at a London clinic that claims to remove microplastics, forever chemicals and herbicides from the blood. But how settled is the science around the health risks of microplastics? To find out, Ian Sample speaks to Dr Stephanie Wright, associate professor of environmental toxicology at Imperial College London’s school of public health. She explains what we know so far about the effects of microplastics in the body, why the science is still evolving, and what we can do to reduce our exposure. Help support our independent journalism at theguardian.com/sciencepod

The number of women choosing to freeze their eggs has increased sharply, according to figures from the UK’s Human Fertilisation and Embryology Authority (HFEA). The number deciding to embark on the process abroad also appears to be rising. Madeleine Finlay speaks to the Guardian journalist Lucy Hough, who recently travelled to Brussels to freeze her eggs. She explains what prompted her decision and how she feels now that the procedure is over. Madeleine also hears from Joyce Harper, a professor of reproductive science at University College London, about what the freezing of eggs involves and why the small odds of success could be driving women to travel to do it. Help support our independent journalism at theguardian.com/sciencepod

In an interview last weekend, Iran’s ambassador to the UN said his country’s nuclear enrichment ‘will never stop’ because it is permitted for ‘peaceful energy’ purposes. It is the latest development in an escalation of tensions over Iran’s nuclear programme, which erupted when Israel targeted the country’s nuclear facilities in June. To understand why enrichment is so important, Madeleine Finlay talks to Robin Grimes, professor of materials physics at Imperial College London. He explains what goes into creating a nuclear weapon, and why getting to the stage of weaponisation is so difficult. Help support our independent journalism at theguardian.com/sciencepod

It has been 25 years since Bill Clinton announced one of humanity’s most important scientific achievements: the first draft of the human genome. At the time, there was a great deal of excitement about the benefits that this new knowledge would bring, with predictions about curing genetic diseases and even cancer. To find out which of them came to pass, and what could be in store over the next two-and-a-half decades, Madeleine Finlay is joined by science editor Ian Sample, and hears from Prof Matthew Hurles, director of the Wellcome Sanger Institute. Help support our independent journalism at theguardian.com/sciencepod

Ever since Pluto was demoted from planet to dwarf planet in 2006, astronomers have been wondering whether Neptune really is the most distant planet from the sun. Now, a new telescope could uncover what lies in the farthest reaches of the solar system. The Vera C Rubin Observatory released its first images this week, and soon the world’s most powerful digital camera will be pointing across the whole of the night sky. Scientists are hopeful that if planet nine exists, the telescope will find it within its first year of operation. Ian Sample is joined by Dr Scott Sheppard, an astronomer at the Carnegie Institution for Science, to find out how Pluto lost its planetary status, why scientists think there could be another super-Earth, and why planet nine has been so hard to find. Help support our independent journalism at theguardian.com/sciencepod

More of us are turning to products containing mushroom extracts, with the medicinal fungi market now worth billions of pounds. Promises of benefits to mental and physical health have seen its popularity spill over from wellness influencers to the shelves of Marks & Spencer – but is there any scientific evidence behind these claims? Ian Sample chats to Madeleine Finlay about the appeal of mushroom drinks and supplements, and hears from the mycologist Prof Nik Money on what we really know about how fungi can affect our minds and bodies. Help support our independent journalism at theguardian.com/sciencepod

The chancellor, Rachel Reeves, has promised £14bn of investment to build the Sizewell C nuclear power plant, kicking off what the energy secretary, Ed Miliband, says will be a ‘golden age for clean energy abundance’. But for critics, the technology’s high costs and lengthy construction times have always eclipsed the benefits of abundant low-carbon electricity. Ian Sample is joined by the Guardian energy correspondent Jillian Ambrose to find out why the UK government is backing nuclear and whether it will help Britain hit its target of net zero by 2050. Help support our independent journalism at theguardian.com/sciencepod

As a companion to the Guardian’s Missing in the Amazon podcast, global environment editor Jon Watts goes in search of answers to the question Dom Phillips was investigating when he was murdered: how can we save the Amazon? In the final episode of a three-part series, Jon encounters a radical new view of the Amazon’s history being uncovered by archaeologists. Far from an uninhabited wilderness, the rainforest has been shaped by indigenous peoples for thousands of years. Jon finds out how their expert knowledge could be harnessed to secure the Amazon’s future. Help support our independent journalism at theguardian.com/sciencepod

As a companion to the Guardian’s Missing in the Amazon, Jon Watts, global environment editor, goes in search of answers to the question Dom Phillips was investigating when he was murdered: how can we save the Amazon? In episode two, Jon meets the people trying to make sure the rainforest is worth more standing than cut down – from a government minister attempting to establish Brazil’s ‘bioeconomy’ to a startup founder creating superfood supplements and a scientist organising night-time tours hunting for bioluminescent fungi. Jon explores new ways of finding value in the forest and asks whether they will be enough to secure its future survival. Help support our independent journalism at theguardian.com/sciencepod

As a companion to the Guardian’s Missing in the Amazon, the global environment editor Jon Watts goes in search of answers to the question Dom Phillips was investigating when he was murdered: how can we save the Amazon? In episode one of a three-part series, Watts explores what’s at stake if we fail to act in time. He hears about the crucial role of the rainforest for South America and the global climate, and looks back at how cattle ranching came to dominate and destroy huge swathes of the forest – pushing it to a dangerous tipping point today. Help support our independent journalism at theguardian.com/sciencepod

The British journalist Dom Phillips and the Brazilian indigenous defender Bruno Pereira vanished three years ago while on a reporting trip near Brazil’s remote Javari valley. The Guardian’s Latin America correspondent, Tom Phillips, investigates what happened to them in a six-part podcast series. Find episode 2 and all future episodes by searching for Missing in the Amazon. Help support our independent journalism at theguardian.com/sciencepod

Vast areas of the ocean are getting darker, according to research based on satellite imaging. Marine ecosystems are governed by faint light changes – from mass nightly migrations to coral spawning cycles – so what happens when that light begins to fade? Ian Sample talks to Prof Tim Smyth from the Plymouth Marine Laboratory about why this darkening is happening and how life in the ‘photic zone’ – the sunlit upper layer that is home to 90% of marine organisms – could be profoundly affected Planet’s darkening oceans pose threat to marine life, scientists say. Help support our independent journalism at theguardian.com/sciencepod

Ian Sample meets Jaap de Roode, professor of biology at Emory University in Atlanta, and author of the book Doctors by Nature: How Ants, Apes and Other Animals Heal Themselves. De Roode explains how a chance discovery got him interested in animal medicine, the amazing ways that creatures use toxins to fight parasites and pathogens, and what humans have learnt about medicine from the animal world. Help support our independent journalism at theguardian.com/sciencepod

Ian Sample is joined by Dr James Kinross, colorectal surgeon and author of the book Dark Matter: The New Science of the Microbiome, to answer all your questions about gut health. In episode two, Kinross explains what else, beyond antibiotics, can damage our microbiome, how we can start to repair it, and gives his top tips for keeping our gut microbes happy. Help support our independent journalism at theguardian.com/sciencepod

Ian Sample is joined by James Kinross, colorectal surgeon and author of the book Dark Matter: The New Science of the Microbiome, to answer all your questions about gut health. In episode one, James explains how the gut microbiome gets set up, how it impacts our early development, and the effect antibiotics can have on our microbes. Help support our independent journalism at theguardian.com/sciencepod

Doctors in the US have become the first to treat a baby with a customised gene-editing therapy after diagnosing the child with a severe genetic disorder that kills about half of those affected in early infancy. Ian Sample explains to Madeleine Finlay how this new therapy works and how it paves the way for even more complex gene editing techniques. David Liu, a professor at the Broad Institute of MIT and Harvard and the inventor of these therapies, also describes the barriers that could prevent them reaching patients, and how he thinks they can be overcome. Help support our independent journalism at theguardian.com/sciencepod

In March 2021, the Toronto-based reporter Leyland Cecco heard about a memo sent by New Brunswick health officials that warned about a possible unknown neurological syndrome thought to be affecting about 40 people. Since then the story has taken many twists and turns, most recently with a peer-reviewed study that concludes there is no mystery illness after all. Cecco tells Madeleine Finlay about the devastating symptoms that patients experienced, and why the research is unlikely to resolve the conflict over what has been causing them. Help support our independent journalism at theguardian.com/sciencepod

Geoengineering, the controversial set of techniques that aim to deliberately alter the Earth’s climate system, may be inching a step closer to reality with the announcement that UK scientists will be conducting real-world experiments in the coming years. To understand what’s happening, Ian Sample is joined by the Guardian environment editor Damian Carrington. Damian explains what the experiments will entail and why scientists are so divided on whether pursuing this research is a good idea. Help support our independent journalism at theguardian.com/sciencepod

For a long time the appendix was considered disposable. After all, millions of people have theirs removed each year and go on to live healthy lives. But as Heather F Smith, a professor of anatomy at Midwestern University tells Ian Sample, researchers are increasingly understanding what this small worm-shaped organ may be bringing to the table in terms of our health. Smith explains how the appendix is linked to both our immune system development and gut health, and why she thinks an increasing interest in the microbiome may bring it to greater prominence. Help support our independent journalism at theguardian.com/sciencepod

Science correspondent Hannah Devlin joins Ian Sample to discuss three intriguing science stories from the week, from a global study that puts the UK third from bottom when it comes to flourishing, to a man who intentionally suffered more than 200 snake bites in the quest to find a universal antivenom and a breakthrough in the quest to understand the contents of the charred Herculaneum scrolls buried when Mount Vesuvius erupted. Help support our independent journalism at theguardian.com/sciencepod

Direct to consumer tests that claim to tell us our biological – as opposed to chronological – age are getting a lot of attention, but what can they really tell us about our health? Science editor Ian Sample talks to Dr Brian H Chen, an epidemiologist at the California Pacific Medical Center Research Institute, who has conducted research into a variety of these tests called epigenetic clocks. He explains what exactly they are measuring and whether, once we have the results, there are any evidence-based strategies we can adopt to lower our biological age. Help support our independent journalism at theguardian.com/sciencepod

Authorities are still trying to understand what triggered the massive power outage that left the majority of the Iberian Peninsula without electricity on Monday. To understand what might have been at play, and whether there’s any truth to claims that renewable energy sources were to blame, Ian Sample hears from Guardian energy correspondent Jillian Ambrose. And Guardian European community affairs correspondent Ashifa Kassam explains what it was like to experience the blackout and how people reacted. Help support our independent journalism at theguardian.com/sciencepod

Just Stop Oil, the climate activism group behind motorway blockades, petrol station disruption and tomato soup attacks on major artworks, has disbanded after staging a final action in London this weekend. To find out why the group has decided to hang up the famous orange high-vis, Madeleine Finlay hears from our environment correspondent Damien Gayle who has been covering Just Stop Oil since its inception. He explains how policy wins and policing crackdowns combined to bring the movement to a close, and what the future of climate activism could look like in its wake. Help support our independent journalism at theguardian.com/sciencepod