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 [email protected] or you can send us a voice note to our WhatsApp number: 07543 306807.

Presenter: Greg Foot

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 [email protected] or you can send us a voice note to our WhatsApp number: 07543 306807.

Presenter: Greg Foot

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 [email protected] or you can send us a voice note to our WhatsApp number: 07543 306807.

PRESENTER: Greg Foot

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 [email protected] or you can send us a voice note to our new WhatsApp number: 07543 306807.

PRESENTER: Greg Foot

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 [email protected] or you can send us a voice note to our new WhatsApp number: 07543 306807.

PRESENTER: Greg Foot

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

Sales of energy drinks are rising and their brightly coloured cans line the shelves of almost every supermarket or grocery store in the UK. But do brands like Monster, Red Bull and Relentless deliver on their promises?

Listener Syed is a consultant radiologist and says he needs to be on his A-Game in his demanding job. He wants to know if an energy drink would be any better than his usual cup of coffee in helping him stay alert. He's also keen to know more about some of the ingredients they contain - things like taurine, guarana and electrolytes. What exactly do they do? And are energy drinks safe to drink regularly?

Presenter Greg Foot has a thirst for knowledge and speaks to expert dieticians and cardiologists to find out if energy drinks live up to the hype. Are they the best thing since sliced bread - or marketing BS?

PRESENTER: Greg Foot

Shampoo ranges hugely in price, from own brand bottles to premium products that promise to improve your hair, leaving it in better condition, stronger and shinier. But can they really deliver?

Listener Sophie sent in a WhatsApp to ask just that, as well as whether we should use different shampoos depending on our hair type, if sulphates or parabens could be harmful to our hair, and if shampoo bars can do the job just as well, and be a greener option?

Greg Foot untangles some of the most common claims by speaking with a clinical Trichologist (someone who has studied the structure, function and diseases of human hair) as well as an expert chemist and pharmaceutical analyst.

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 [email protected] or you can send us a voice note to our new WhatsApp number: 07543 306807.

PRESENTER: Greg Foot

Two products dominate the market for nasal sprays that claim to reduce symptons of a cold - Vicks ‘First Defence’ and Boots ‘Dual Defence’. But do they work?

Listener Leah got in touch because she catches lots of colds from her young son and wants to know if they can help her get over them more quickly. She also wants to know if they’re safe to use regularly and how long you should take them for.

Presenter Greg Foot sniffs out the evidence and talks to a leading expert who’s dedicated most of his career to investigating cold remedies.

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 [email protected] or you can send us a voice note to our new WhatsApp number: 07543 306807.

PRESENTER: Greg Foot

In the run up to Christmas, many parents will be checking on their battery supplies ahead of Santa bringing gifts that require them. But do branded batteries, that promise more power and longer life at a higher price point, really deliver it?

Listener Peter got in touch asking just that, as well as whether batteries have an expiry date?

Greg Foot recruits some year 7 pupils and their teacher to help him perform a test to find out, and speaks to one of the country’s leading scientists about what gives a battery more power, or helps it store more energy.

You can also hear more about the difference between single use, and rechargeable batteries in our longer podcast episode 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 [email protected] or you can send us a voice note to our new WhatsApp number: 07543 306807.

PRESENTER: Greg Foot