How chicken got big. Dr Chris van Tulleken unwraps the forces that shape what we eat. Listen and subscribe on BBC Sounds - just search for Fed with Chris van Tulleken.

Greg Foot returns to investigate a whole new batch of so-called wonder products suggested by you, the listeners. Sliced Bread is back for a new series from Thursday 28 September, 2023 on BBC Radio 4 and BBC Sounds, with new episodes available weekly on Thursdays on BBC Sounds and wherever you get your podcasts.

Charlotte and Amit dive into the story of microwaves and ask if they have enough power for a comeback. Around nine out of ten of us have a microwave in the UK, making it a trendy gadget. But most of us use it for reheating food or zapping a microwave meal. Amit Katwala and Charlotte Stavrou find out if we are missing a trick by not incorporating microwaves further into our cooking and delve into whether these gadgets can help us during the cost of living crisis. We meet MasterChef winner Tim Anderson who explains why he’s a self-described ‘microwave evangelist’ as he creates an emergency cookie for us in the studio. Alan Kelly, a professor in Food Science at University College Cork, tells us about the inner workings of microwaves and we trace the device's history, evolving from radar technology used in the Second World War. Food writer Bee Wilson, author of the new book The Secret of Cooking, charts how her mother’s attitudes to microwaves changed through the years while Louis Platman, a curator at the Museum of the Home, tells us when microwaves began to appear in our homes. Producer: Emily Uchida Finch A Whistledown production for BBC Radio 4

It’s not an understatement to say that microchips are now everywhere - from phone chargers to our beloved pets, there’s probably a microchip embedded within. But who invented them and how do they dictate computing power? Amit Katwala and Charlotte Stavrou dig their hands into a bowl of microchips for this episode of All Consuming. They meet Ken Shirriff, a former engineer at Google, who explains the crucial role of transistors in microchips, which are tiny switches etched into the silicon wafer. When the first microchip was invented in the 1950s there were just three transistors, but some microchips can now contain billions. Over the decades, this has hugely increased computing power and changed our daily lives. But microchip fabrication plants - called ‘fabs’ to those in the industry - require large volumes of water. Amit and Charlotte speak to Anurag Bajpayee, the co-founder of a company that recycles water at microchip manufacturing plants and Dr Yu Shu, a researcher at Oxford University, who is working on a novel method of creating microchips which are less harmful to the environment. We end our tour of the world of microchips with a visit to the University of Sussex quantum lab where they’ve recently had a breakthrough in quantum microchips, which could change the world in a way that we can’t yet compute. Producer: Emily Uchida Finch A Whistledown production for BBC Radio 4

Around 70 million pairs of denim jeans are sold every year in the UK. They come in a dizzying array of shapes and styles, but the essentials haven’t changed since they were first conceived in the Californian gold rush 150 years ago. Charlotte Stavrou and Amit Katwala continue their exploration of our culture of consumption by unpicking our abiding love affair with denim. Mohsin Sajid, denim designer and lecturer at some of the UK’s top fashion colleges, takes us through the history of denim which originated as tough workwear, to its golden age of 1950s American youth culture. Meanwhile, Bryan Szabo who runs an annual raw denim fade competition - the Indigo Invitational - explains how denim allows wearers to leave an imprint on their clothes and tell a unique story. Sir John Hegarty discusses his agency’s relaunch of Levi’s 501 jeans in the 1980s when an irresistible combination of visual and music references made this item so desirable it became a symbol of rebellion in the Cold War. We hear from Nicolai Khalezin of the Belarus Free Theatre about how denim was used in Belarus to bolster a protest movement. Produced by: Ruth Abrahams and Emily Uchida Finch A Whistledown production for BBC Radio 4

Charlotte Stavrou and Amit Katwala take a deep dive into the world of Board Games - from the Ancient Egyptian game of Senet to more recent classics like Monopoly and Catan. Along the way, they talk history with Dan Jolin, the co-founder of the board game magazine Senet, meet the acknowledged master of the modern strategy game Reiner Knizia who has invented over 800 games, and learn the tricks of the trade from world Monopoly champion Nicolo Falcone who reveals why getting stuck in jail isn't always a bad thing. Presented by Charlotte Stavrou and Amit Katwala Produced by Carrie Morrison A Whistledown production for BBC Radio 4

With over 90% of our photos now captured on phones, Charlotte Stavrou and Amit Katwala go in search of what cameras mean today and how they have evolved since their origins in the 19th century. Ruth Quinn, curator of photography and photographic technology at the National Science and Media Museum in Bradford, shines a light on how photographic cameras were born out of a Victorian fascination with chemistry and optics. Long-time Kodak employee, Steve Sasson, reveals how a brief to play with a new bit of kit in the 1970s led to his invention of the digital camera. Meanwhile, Dr Alix Barasch, Associate Professor of Marketing at the University of Colorado, discusses the ways phone cameras and image-sharing apps are not only changing how we process our environment but also what we do. And Charlotte takes a trip into the dark room with photographer Alia Romagnoli to develop a portrait taken on a film camera for a recent series on queer men and masculinity and discusses why these old manual devices are back in fashion with Gen Z. Producer: Ruth Abrahams A Whistledown production for BBC Radio 4

Amit Katwala and Charlotte Stavrou explore our unending appetite for manicures and find out that it's much more than just a buff and cuticle pushback. Gel, acrylics, French tips - there's a seemingly endless list of services that can be applied to our fingertips. But some salons have taken nail art to the next level as Charlotte found out when she visited NUKA nails in West London. While manicures seem to be enjoying a heyday, nail treatments aren't a modern phenomenon as writer Suzanne E Shapiro explains as she takes us on a journey from Ancient Egypt to the French Riveria of the 1920s. Consultant dermatologist Dr Deirdre Buckley is also on hand to warn us about the emergence of plastic allergies in manicure lovers and we also uncover the dark underside of the industry when it comes to trafficked salon workers. Producer: Emily Uchida Finch A Whistledown production for BBC Radio 4

From the running boom at the end of the 19th century to a lockdown-inspired desire to lace up, running shoes have evolved to fit the shape of our lives for over 150 years. Charlotte Stavrou and Amit Katwala explore how they keep pace with trends, innovations, and even our ambitions. Thomas Turner, author of The Sport Shoe: A History from Field to Fashion, reveals the role of Victorian periodicals in spreading tips and recommendations to fellow runners. Elizabeth Semmelhack, director and senior curator of the Bata Shoe Museum in Toronto, takes us to 1970s California where running shoes signalled a new kind of aspiration for baby boomers, driven by new brands and mass marketing. Dr D’Wayne Edwards, sports footwear designer and founder of Pensole Lewis College, shares insider stories of being one of just two black footwear designers when he started in 1989, and how he’s bringing a more diverse cohort into the industry today. Meanwhile, Jessica Morgan, journalist, and editor, unboxes a memory of a special pair of running shoes that saw her through her darkest times. And we jog down to Hackney Downs park in east London to meet Michael Doughty from Hylo Athletics who left a career in football to set up a running shoe company with green ambitions. Producer: Ruth Abrahams A Whistledown production for BBC Radio 4

Charlotte Stavrou and Amit Katwala go mushy for houseplants in this episode of All Consuming where they explore our culture of consumption. Philodendrons, Hoyas, Monsteras - the list of plants available to consumers is now almost endless and these green companions became a crucial part of our home during lockdown when we craved the outdoors. In recent years, our love for houseplants has seen the plant market explode - but at what cost? Charlotte and Amit meet Jacob James, a seller of rare plants at the Royal Chelsea Flower Show, who reveals that there’s been a recent crash in rare houseplant prices. We check in with historian Catherine Horwood to find out how houseplants first entered the home and ecologist Dr Adam Cross gives us a fly’s eye view of a rare carnivorous plant. Amateur biologist Sebastian Cocioba tells us how he hacks orchids for a special Mother’s Day present. Presenters: Amit Katwala and Chalotte Stavrou Producer: Emily Uchida Finch A Whistledown production for BBC Radio 4

From the first spectacles that perched on noses around 750 years ago to AI-enhanced glasses for the visually impaired, we have been harnessing science - and design - to help us see for centuries. Charlotte Stavrou and Amit Katwala peer into the wonders of glasses that bring the world into focus for an estimated 4 billion adults around the world. We visit the UK’s largest collection of eyewear - the British Optical Association Museum where we meet curator, Neil Handley. Jessica Glasscock, author of Making a Spectacle, reveals how the Harlequin frame – better known as the cat eye frame - transformed glasses for women in the US in the 1930s. Meanwhile, historian Jo Gooding explores the role of the British welfare state in influencing glasses styles and the unintended consequences that arose from state provision. For the UK consumer, things changed dramatically in the 1980s and Graham Daldry, former Creative Director of Specsavers shares the secrets of the winning ‘Should’ve gone to…’ campaign. And taking us to the next level, Karthik Mahadevan, the Founder and CEO of Envision gives us a demo of glasses that use AI and camera technology to assist people who are severely visually impaired. Presenters: Charlotte Stavrou and Amit Katwala Producer: Ruth Abrahams A Whistledown production for BBC Radio 4

Did you know there was a time when you could only buy green tea in the UK? Tea is now a staple product for most of us, but it has a long and complicated past. In this episode of All Consuming, Charlotte Stavrou (née Williams) and Amit Katwala steep themselves in the intriguing history of tea. They talk to advertising expert Paul Feldwick to get the inside story of how chimps were used to advertise the drink, historian Jane Pettigrew explains how tea reached our shores from China, and we also delve into the links between tea and sympathy with psychologist Dr Andrea Shortland. Producer: Emily Uchida Finch A Whistledown production for BBC Radio 4

Charlotte Stavrou and Amit Katwala return for a second series of investigations into the products that have changed the world. Coming to BBC Sounds weekly from 20 July 2023.

All Consuming hosts Charlotte Williams and Amit Katwala talk to presenter Greg Foot about the return of Sliced Bread, his Radio 4 series which explores promising sounding wonder products and sees whether their claims stand up to scrutiny. You can listen to the series by searching for Sliced Bread on BBC Sounds.

From an illusive science fiction dream in the 1980s, to very real headsets in homes across the world today - virtual reality is making a genuine impact on our lives and social interactions. Amit Katwala and Charlotte Williams immerse themselves in the virtual world to find out where the innovative technology is leading, checking in on today’s prototypical “metaverse” and VR’s growing influence on art, entertainment and science. We hear from Dr Alastair Smith about VR’s revolutionary uses in the study of psychology, Dr Trudy Barber sheds a light on the social connections forming inside the metaverse, while interactive experience director May Abdalla invites us into the world of her award-winning VR project, Goliath: Playing with Reality. Presented by Charlotte Williams and Amit Katwala Produced by James Tindale A Whistledown production for BBC Radio 4

Charlotte Williams and Amit Katwala trace the sometimes shocking truth behind the history of the light bulb, following its evolution from carbon spitting hazard to energy efficient LED. We hear from media historian Markus Krajewski about how a cartel of companies conspired to limit the lifespan of light bulbs in the first known example of ‘planned obsolescence’. Nobel prize winning physicist Hiroshi Amano talks to us about how his discovery of the blue LED light has changed the world, and we speak to Tom Bramell whose job is to to look after a lightbulb which has been on for 121 years. Presented by Charlotte Williams and Amit Katwala Produced by Emily Finch A Whistledown production for BBC Radio 4

The average cost of a funeral in the UK is just over £4000 - and can be a lot more. Charlotte Williams and Amit Katwala explore how social and financial pressures are changing the way we do funerals, as more and more people turn to cheaper greener alternatives. They trace the history of the funeral and its many associated traditions with funeral historian Dr Helen Frisby, and unpick so-called funeral poverty with Lindesay Mace from Quaker Social Action. Dr Kate Woodthorpe from Bath University explains the birth of the Funeral Director and Dan Garrett, the CEO of Farewill, discusses how the industry is adapting to changing attitudes to death and the big rise in "personalised funerals". Presented by Charlotte Williams and Amit Katwala Produced by Bukky Fadipe A Whistledown production for BBC Radio 4

Batteries are everywhere in modern society. They’re in our phones, laptops and cars, or inside the classics - like torches, portable radios, or TV remotes. They’re inside drones probing deep beneath the ocean or providing juice to the Mars rover. In an electrifying episode of All Consuming, Amit Katwala and Charlotte Williams explore the history of the energy storage devices that changed the world. We check in with the curator of contemporary Science at the Science Museum, Dr Sophie Wearing, to learn about the unlikely origin of the term “battery” and the early uses of energy storage. We also we get up to speed with Electric Vehicle Batteries with the Faraday Institution’s chief scientist, Sir Peter Bruce. Battery recycler Sam Haig deconstructs lithium-ion battery recycling and, to get the bigger picture, we hear from pumped-storage hydro expert Alex Campbell. A Whistledown production for BBC Radio 4

Amit Katwala and Charlotte Williams explore the world of e-cigarettes and vapes, tracing their extraordinary growth and asking whether they’re life savers or something more insidious. We hear from Time journalist Jamie DuCharme, author of the book Big Vape, about the rise and fall of the e-cigarette firm Juul who recently paid out over $430 million after being accused of targeting teenagers with its advertising. Shaun Yendalls, the owner of two vape shops in South London, explains why his staff actively try to stop people buying his products and Scott Butler from Material Focus details the massive environmental impact of the new fad for disposable vapes. Presented by Charlotte Williams and Amit Katwala Produced by Bukky Fadipe A Whistledown production for BBC Radio 4

In recent years our supermarket shelves have undergone a transformation. Sections once devoted solely to meat and animal products have been partitioned to include a new plant-based category, with everything from spins on classics like tofu and seitan, to modern products like Quorn and the lab-designed Impossible and Beyond burgers. In this episode of All Consuming, Charlotte Williams gives you something to chew on in a surprisingly meaty topic - examining the plant-based product revolution and its potential environmental benefits, and finding out if “vegan” is a dirty word. Charlotte meets author and entrepreneur Thomasina Miers to discuss dialling back on our high-carbon diets, checks in with vegan-accredited farmer Laurence Candy, learns about the health and environmental benefits of plant-based alternatives from Dr Chris Bryant, and breaks bread with vegan YouTube superstar Gaz Oakley. A Whistledown production for BBC Radio 4

Charlotte Williams and Amit Katwala explore how Britain went soft on toilet paper. 1-ply, 2 ply, 3 ply, quilted - there’s a lot of choice when it comes to choosing what toilet paper to buy. But soft toilet tissue is a relatively new invention. Our lavatorial habits have evolved over time and author Sophia Gholz gives us the lowdown on how pottery, magazines and corn cobs were all at one time used for the mundane but necessary task of keeping ourselves clean. For many people, the smell and feeling of a specific British brand of paper is etched into their collective memory. Dr Alice White of the Wellcome Collection explores official resistance to putting soft paper in schools and hospitals. Consumer psychologist Dr Paul Marsden is also on hand to explain why toilet paper is often the must-buy product in times of national emergency. And marketing consultant Paul Duncanson gives a behind-the-scenes account of one of the most enduring - and successful - toilet tissue advertisements ever produced. Producer: Candace Wilson A Whistledown production for BBC Radio 4

Much has been written of Vinyl’s resurgence - it’s the format that refuses to die, electrifying fans young and old across the decades. But, we’ve often forgotten about the Lennon to vinyl’s McCartney - the venerable turntable. In this episode of All Consuming, hosts Charlotte Williams and Amit Katwala get into the groove to find out why turntables just keep spinning us around. We unearth the history of recorded sound, including the French invention that drew audio waveforms and predated Edison’s phonograph and get up to date with the latest stats on vinyl’s revival. Amit meets Audiophile researcher Marc Pearlmann to consider the claims that vinyl on high end turntables “sounds better” than CDs, we check in with Wolverhampton record store owner Claire Howell, meet veteran turntable manufacturer Roy Gandy and Charlotte gets a lesson in DJ-ing from a very special guest... Producer: James Tindale A Whistledown production for BBC Radio 4

Charlotte Williams and Amit Katwala explore the burgeoning non-alcoholic drinks market and explore its origins, dating all the way back to the Middle Ages. In a whistlestop tour through history, they trace the influence of the Temperance Movement in the US on drinking habits and examine how attitudes to wellness and mental health have shaped the market today. Producer: Candace Wilson A Whistledown production for BBC Radio 4

From the artisans of Ancient Egypt, to the revolutionary parfumiers of Renaissance France and the designers working digitally in the dungeons of petrochemical labs, perfume is one of the most available and affordable luxuries. Initially exclusive to the halls of royalty, it's now available for £15 from your local chemist - the perfume industry continues to grow with our consumer culture. Are you smelling a story? In this first episode of All Consuming, hosts Charlotte Williams and Amit Katwala make scents of the perfume industry. They sniff out why fragrance films are so fantastical, catch a whiff of how industrial perfume producers manufacture at industrial scale, and hold their noses as actors take “method” to fragrant new frontiers. Charlotte meets the perfumer to the stars Azzi Glasser and takes the chance to smell bespoke fragrances designed for Hollywood A-listers. Amit introduces us to nose-in-the-know Luca Turin, a biophysicist who moonlights as a fragrance author. And smell psychologist Rachel Herz reveals why the smells of those we love can sometimes become repulsive. Producer: James Tindale A Whistledown production for BBC Radio 4.

From turntables to funerals, Charlotte Williams and Amit Katwala reveal the truth behind what we’re all consuming.