Saunas and cold plunge pools are popping up everywhere in the UK, bringing fiery heat and icy cold to a beach, city farm or park near you. Their users will be ready with all the reasons why it’s good for both the mind and the body. But what’s the evidence for the benefits of sauna and cold plunge? In this episode from April, Madeleine Finlay hears from Ian Sample and Dr Heather Massey, associate professor at the University of Portsmouth’s extreme environments laboratory. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

In this episode from January 2026, Ian Sample puts listeners’ questions about dreams and nightmares to Dr Michelle Carr, the director of the Dream Engineering Laboratory in Montreal’s Centre for Advanced Research in Sleep Medicine, and the author of the book Into the Dream Lab. They look at why we dream, what we can learn by examining our dreams, and what we can do when dreams turn into nightmares. Carr gives her top tips for taking charge of our dreams and trying to influence their content. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Science correspondent Nicola Davis investigates the strange story of Tam O’Braan and his attempts to grow tea in Scotland. In episode three of this mini-series first broadcast in October 2025, all of O’Braan’s lies come to a head and it is revealed where he was sourcing the tea being supplied to hotels and shops. At trial, O’Braan takes the stand and the Scottish growers finally get some answers. But what remains today of the Scottish tea industry that O’Braan instigated?. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Science correspondent Nicola Davis investigates the strange story of Tam O’Braan and his attempts to grow tea in Scotland. In episode two of this mini-series first broadcast in October 2025, Nicola hears how O’Braan’s network of Scottish tea growers began to have suspicions about exactly what he was selling and where it came from, and how cutting-edge science helped provide some answers. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Science correspondent Nicola Davis investigates the strange story of Tam O’Braan and his attempts to grow tea in Scotland. In episode one of this mini-series first broadcast in October 2025, Nicola looks back on her first meeting with O’Braan while working on a feature about tea plantations in the UK. He was selling his award-winning Scottish-grown tea to some of the UK’s finest hotels, but something didn’t quite add up. And Nicola wasn’t the only person taking an interest in his story. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

The first person has been treated with a highly anticipated new gene therapy that aims to turn back the clock on ageing cells. The trial is aimed at retinal cells, with the hope that encouraging them to behave as if they were young again could improve sight in the affected patients. If it proves to be safe, it could open the door to a whole raft of therapies based on the emerging field of cellular rejuvenation. To understand more about this cutting edge research, Madeleine Finlay hears from science editor Ian Sample and from Paul Knoepfler, professor of cell biology and human anatomy at the university of California, Davis.. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Scientists often talk about the importance of flora and fauna to the health of our planet, but Dr Toby Kiers, an evolutionary biologist and founder of the Society for the Protection of Underground Networks, wants us to consider another force: fungi. Her work charting the planet’s vital underground systems has earned her numerous awards, including a MacArthur fellowship and a Tyler Prize for Environmental Achievement (sometimes called the ‘green’ Nobel). She tells Ian Sample about her work mapping fungal networks on the remote Palmyra Atoll in the Pacific Ocean, and what the research reveals about fungi’s often invisible role. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Men’s average testosterone levels have halved over the past 50 years, according to scientists who say society is facing a male fertility crisis. Rising levels of obesity and diabetes are expected to play a part, but the team behind the work suggest that environmental factors such as endocrine-disrupting chemicals – which can be found in various household items – and global heating could also be factors in the apparent striking decline. Ian Sample speaks to science correspondent Hannah Devlin to find out how the work has been received and what the researchers want to see happen in response to their finding. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

In the last 50 years, Britain has lost an astonishing 73 million wild birds from its landscape, according to the British Trust for Ornithology. Habitat loss, pesticides, disease, cats and the climate crisis mean there are fewer birds than ever before. For children and young people it can be difficult to appreciate the scale of the loss due to a psychological phenomenon called ‘shifting baseline syndrome’, where each generation inherits a degraded version of the environment, and therefore doesn’t notice the overall decline. But Gen Z are bucking the trend. Thanks to social media and the Merlin Bird ID app, birding has become cool. To find out what we’re missing from the dawn chorus, and why young people are embracing birdwatching, Madeleine Finlay hears from the writer Robert Macfarlane and from Jess Painter, a member of the RSPB’s youth council. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>

Researchers claim they are closer to creating life from nothing after building tiny, quivering blobs that use lab-made DNA to feed, grow and multiply in a dish. To find out how significant this step is, and where scientists hope it will lead, Madeleine Finlay hears from co-host Ian Sample and from Kate Adamala, professor of genetics at the University of Minnesota. Help support our independent journalism at <a href="https://www.theguardian.com/sciencepod">theguardian.com/sciencepod</a>