Science Weekly

Revisited: Saunas and cold plunges, where does the evidence stand?

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 theguardian.com/sciencepod [https://www.theguardian.com/sciencepod]

Revisited: The surprising science of dreams and nightmares

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 theguardian.com/sciencepod [https://www.theguardian.com/sciencepod]

Revisited: A Scottish tea mystery, episode three – a bag for life

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 theguardian.com/sciencepod [https://www.theguardian.com/sciencepod]

Revisited: A Scottish tea mystery, episode two – the list

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 theguardian.com/sciencepod [https://www.theguardian.com/sciencepod]

Revisited: A Scottish tea mystery, episode one – green shoots

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 theguardian.com/sciencepod [https://www.theguardian.com/sciencepod]