Is sourdough the best thing since Sliced Bread? It’s the last episode in the current series so I thought it was about time I investigated this! Listener Janet got in touch wanting to know whether sourdough really does live up to the hype. Is it better for our digestive health than other breads? Is it made with fewer additives? And do the cheaper sourdough loaves we can buy in the supermarket really cut it - or are they just ‘sourfaux’? To find out, I went to a baking school to make a sourdough loaf from scratch, learning about the process and ingredients that go to make the sort of sourdough you’d find at an artisan or traditional bakers - and might cost over five pounds. And I speak to one of the world’s leading nutritional experts on bread to find out which types we should eat for our health. This series, we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad, and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our WhatsApp number: 07543 306807. PRESENTER: Greg Foot PRODUCER: Simon Hoban

Mascara is a crucial element of many a make-up bag - but can mascaras really deliver on their promises of longer, fuller, or curlier lashes? Listener Kath got in touch to ask exactly that. She also wants to know if you pay more for mascara, do you get better results? How should we remove it - and what about waterproof products that are tough to take off? Are we potentially damaging our lashes? Greg Foot sets his sights on investigating by recruiting some regular mascara wearers to try out differently priced products, as well as speaking to a consultant dermatologist and cosmetic chemist to find out. This series, we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad, and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our WhatsApp number: 07543 306807. PRESENTER: Greg Foot PRODUCER: Kate Holdsworth

Do toothpastes promising to repair enamel and help with sensitive teeth really work? We've all been there - you go down the supermarket aisle to grab toothpaste and suddenly you’re faced with an ocean of the stuff, all promising to do different things. Buzz-phrases like ‘protect’ and ‘repair’ all vie for your attention. But just what are the ingredients in all these different toothpastes? And do they live up to the marketing hype? In this episode we hear from three listeners keen to find out: Bernadette has sensitive teeth, Deirdre is concerned about her enamel and Melvyn wants to protect his gums. Can presenter Greg Foot find a toothpaste that will work for them and leave them all smiles? This series we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad, and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our WhatsApp number: 07543 306807. PRESENTER: Greg Foot PRODUCER: Simon Hoban

Sleep is never more important than when you aren’t getting any. And there’s a large range of night time teas, herbal tablets and relaxing oils and sprays that promise to help you get some. But can they really deliver? Listener Corrine got in touch after struggling with her sleep post menopause, wanting to know if there was any evidence to back up the claims of various natural sleep aids. Can they give her the restful night’s sleep she craves – or is it just a waste of money? She sets Greg Foot the job of finding out, by speaking to an Expert Sleep Physiologist, as well as a Professor in Clinical Pharmacology, Therapeutics and Toxicology. This series we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad, and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our WhatsApp number: 07543 306807. PRESENTER: Greg Foot PRODUCER: Kate Holdsworth

We spend a lot of time on them so it’s important to get the right mattress. But buying one can be confusing. Some use springs while others are made out of foam - or there’s a combination of both. Then there’s memory foam, with brands like Tempur claiming to make their mattresses out of ‘proprietary’ material. And can a good mattress help to alleviate back pain? These are the questions keeping listener Stephen up at night and he tasks presenter Greg Foot with finding out more. Greg speaks to experts in the mattress industry and a sleep specialist, looking at the scientific evidence to test whether the claims made by mattress manufacturers live up to the marketing hype. This series, we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad, and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our WhatsApp number: 07543 306807. Presenter: Greg Foot Producer: Simon Hoban

After the Sliced Bread episode on shampoo, a number of listeners got in touch to request a follow-up episode on conditioners. So of course, we obliged. Listener Katie wanted to know what they actually do to our hair, if they can deliver on promises for shinier, smoother, or stronger locks – and whether leave-in treatments could be more effective than conditioners you wash off in the shower? Listener Franziska also got in touch, as she wondered if we could also have a look at heat protection products. She wanted to know what’s in them, can they offer our hair any protection while styling, and is there a difference between the effectiveness of sprays or creams? Greg Foot rinses out the claims on both, speaking once again to the experts from Shampoo – also available on BBC Sounds. This series, we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad, and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our WhatsApp number: 07543 306807. Presenter: Greg Foot Producer: Kate Holdsworth

Listener Isla, 11, wants to know if bottled water from the UK's biggest selling brands such as Evian and Buxton is cleaner, healthier, cheaper and greener than the stuff that comes from the tap. Greg Foot drills down into the subject, investigating the claims made by manufacturers of bottled water. Does it make any difference if water has spent years underground being "filtered by rocks" before being bottled? Are there more minerals in bottled water than in tap? And even though companies are making more of their bottles from recycled plastic, what’s the environmental impact? Greg speaks to experts including a lecturer in water chemistry, an environmental NGO and a water sommelier (yes, they’re a thing!) who explains why some bottled water can cost more than a hundred pounds. This series, we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our WhatsApp number: 07543 306807. PRESENTER: Greg Foot PRODUCER: Simon Hoban

When it comes to shop-bought painkillers, there are rows and rows of shelves dedicated to them in supermarkets and pharmacies – ranging from own-brand tablets, to more expensive capsules and caplets, as well as branded packets that promise to work faster, and target specific pain. Listener Hannah got in touch all the way from Tunisia to ask the questions – what’s the difference between paracetamol, ibuprofen or aspirin? Can certain painkillers target specific pain? And are any of them able to deliver faster pain relief than others – particularly the pricier branded ones? Greg Foot swallows all the information available, and talks to experts in clinical pharmacology and biochemistry to find out. This series, we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our new WhatsApp number: 07543 306807. PRESENTER: Greg Foot PRODUCER: Kate Holdsworth

In this episode presenter Greg Foot investigates three products that promise to make washing your laundry better for the planet. Listener Clare wants to know if the Ecoegg she’s using really is a greener alternative to liquid detergent and whether the cleaning pellets inside are harmful to the environment. Another listener, Jane, got in touch about laundry sheets – strips of concentrated detergent that go inside the washing machine’s drum. Is the slightly higher cost worth it to cut down on waste? And finally Mary wanted to know about filters that capture harmful microfibres which are shed from our clothes in the washing process and get into the environment, causing huge problems for marine life. This series, we’re testing and investigating your suggested wonder-products. If you’ve seen an ad, trend or fad and wonder if there’s any evidence to back up a claim, drop us an email to sliced.bread@bbc.co.uk">sliced.bread@bbc.co.uk or you can send us a voice note to our new WhatsApp number: 07543 306807. PRESENTER: Greg Foot PRODUCER: Simon Hoban

Petrol is something millions of drivers around the UK rely on, but when faced with the choice of what to fill up with at the pumps, many wonder what is the difference between regular and premium unleaded? That’s exactly what listener Irfan wanted to know, and if premium can really deliver on its promises to make your car more efficient, take you further, and clean out your engine for a higher price tag. Greg Foot drives the investigation into unleaded petrol, what’s changed since we moved from E5 to E10 as our standard, what makes premium special, can it take you further, and whether our carbon footprint is better with one than the other? PRESENTER: Greg Foot PRODUCER: Kate Holdsworth