Sense about Science ? equipping people to make sense of science and evidence
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- Second-hand and chemical free
- Mumsnet & Ask for Evidence
- Context is crucial
- Extraordinary claims need extraordinary evidence: The importance of skepticism
- Who will take responsibility?
- The "accuracy" of screening tests
- Hightable with Tracey Brown: Asking for Evidence to make Sense About Science
- EU GM plant cultivation - how did we get to this weird situation?
- PETA says milk is linked to autism
- Beautiful Science
Posted by Chris Peters on 30 September 2014
A fortnight ago, when my wife mentioned we were planning on getting a second-hand pram, one of her colleagues firmly remarked: “You shouldn’t buy anything second-hand – why would you put your baby’s life at risk?”. As expectant parents you’re susceptible to the hard sell and bombarded with conflicting advice, but at times like this asking for evidence can help. Where did this second-hand claim originate? I decided to do a bit of digging.
Car seats and mattresses
The problem with second-hand things is you don’t always know their history – for a car seat that means you wouldn’t know if it was damaged as a result of a car accident.
It seems second-hand mattresses are similarly a bad idea, as soft mattresses have been linked to cot death. Seeing as a new mattress for our second-hand Moses basket is a little under £20, it’s a price worth paying.
It turns out my wife’s colleague vaguely remembered an article about the dangers of second-hand car seats – but she’d taken it further and decided against any second-hand items for her children. The original article seems to have come from a press release issued by the Baby Products Association which quite openly states it was “set up with the objectives of promoting the baby and nursery products sector in both the UK and Europe.” It’s always worth asking questions rather than just accept things at face value. “Who made the claim?” “Where did the information come from?”
Pure, safe and chemical-free
We have splashed out on a bedside crib which came with a brand new mattress proudly boasting to be ‘chemical-free’. Something that we at Sense About Science have already found is completely meaningless.
I asked Mothercare for evidence about this claim and they replied quickly saying “Chemical-free is a term used in marketing to imply that a product is safe, healthy or environmentally friendly because it only contains natural ingredients.” Mothercare accepts that the term is a ‘misnomer’ as “nothing that physically exists in Earth’s ecosystems is free of chemicals”.
But it’s a shame that Mothercare continues to misinform people by using the phrase ‘chemical-free’ in its marketing, as well as perpetuating the myth that natural is always better than synthetic. I’ve asked Mothercare to amend this claim and I’m waiting to hear back.
In the meantime it’s great to see Mumsnet championing the Ask for Evidence campaign by featuring it as this week’s ‘Campaign of the Week’. As a Voice of Young Science member put it: "As father to a one year old I see this area as a minefield of misinformation so Mumsnet getting on board is excellent."
Posted by Chris Peters on 29 September 2014
There are so many different arguments about what we should and shouldn't do... how to raise an autistic child, fight dementia, cut the environmental impact of waste collection, or reduce obesity. You should follow this diet, change school meals, limit phone use, avoid plastic. Or should you? Confused? Frustrated?
Some of these claims are based on reliable evidence and sound science, but many are not. None of us want to be exploited by misleading information or products that don't work. But there’s something you can do to protect yourself from misleading information – Ask for Evidence is helping thousands of people to find out more about the evidence behind claims they hear.
And that’s exactly why Mumsnet, the UK’s biggest network for parents, is featuring Ask for Evidence as its “Campaign of the Week” this week.
Justine Roberts, co-founder and Chief Executive, Mumsnet.com:
“Parents and those expecting are bombarded with often conflicting advice and product claims, at a time when hormones are raging and you're most susceptible to the hard sell. Likewise conception difficulties and sub-fertility can be heartbreaking for women and their partners, and it's understandable that some may be tempted to try unproven methods to help them conceive a much-wanted baby. The way to deal with the bombardment is to ask questions. This campaign epitomises the need to ask for evidence rather than just accept things at face value.”
Posted by Volunteer on 09 September 2014
“Lack of sleep linked with depression”
“Divorce linked to smoking”
“Mother’s diet linked to childhood obesity”
Do these types of headlines look familiar to you? Newspapers, health websites and adverts for the latest ‘super foods’ regularly claim that a new ‘link’ has been discovered. But it’s important to look a little deeper when you see these sorts of headlines because with these ‘link’ stories, context is crucial.
The problem is that the word ‘link’ implies causation and assuming a ‘link’ is causal can lead you to the wrong conclusion. For example, a ‘link’ between sleeping with the light on and shortsightedness in young children made people think leaving a night light on makes you shortsighted. It turns out that the parents of shortsighted children are more likely to be shortsighted themselves (since shortsightedness is partly genetic), and this also means they are more likely to leave the light on in their children’s rooms. So night lights don’t cause shortsightedness. It is instead shortsightedness in parents that leads to both shortsightedness in their children and a night light being used.
It’s important to look at the context of a correlation to find out whether there really is a causal ‘link’. Try keeping in mind the principle that “correlation does not imply causation” to help weigh up whether a ‘link’ story is credible.
The dose makes the poison
It is becoming common knowledge that red wine and grapes contain a chemical called resveratrol which is ‘linked’ to longevity and cancer prevention. So will drinking lots of red wine make you live into your 90s and never get cancer? Unfortunately it probably won’t.
There’s some evidence from animal tests and experiments on cells grown in the lab that resveratrol may have an anti-cancer effect, but very little is known about its effects in humans. And many of the studies showing this anti-cancer effect have used doses of resveratrol that are far higher than the dose you could get in your diet. So drinking red wine will never be an effective way to prevent cancer.
Resveratrol is also marketed as an ‘anti-aging elixir’ in beauty products. Dr Cat Ball from the Biochemical Society decided to ask for evidence behind one of these products. She was sent a study which found that a resveratrol-containing solution increased lifespan – in mice, with the caveat that the researchers weren’t sure whether it was the resveratrol that was actually causing the effect.
Dose is just one part of the context behind a ‘link’ story. If you live in the UK and sit in the sun for just 10 minutes each day, your chances of developing skin cancer will be much lower than someone living in Australia who sunbathes daily for hours. And surely it’s obvious that putting a product containing a specific ingredient on your skin won't have the same effect as eating something with that ingredient? Unfortunately this is an assumption we see all too often. Mathilde Thomas, founder of beauty brand Caudalie, advised in a Daily Mirror article that you should eat grapes because they are “full of antioxidants, which help to give you really beautiful skin”. I asked Caudalie for evidence, and they got back to me explaining how antioxidants act by “inhibiting the oxidation of other molecules”. I was then told that: “Grapeseeds are very rich in polyphenols, such as [those in] our cosmetic range. This is why you can prevent oxidation by eating grapes and/or applying our creams and serums”. But there’s no reason to assume that applying something to your face will have the same effect as eating it. Caudalie failed to provide evidence that polyphenols, when consumed in grapes, either end up in your skin or can in any way work to make your skin “beautiful”.
Asking for Evidence can help
Next time you see a ‘link’ story or come across extraordinary claims like the one made by Caudalie, you can Ask for Evidence to find out the context, and see how robust the ‘link’ actually is – extraordinary claims need extraordinary evidence.
Posted by Volunteer on 01 August 2014
Guest post by Grace Gottlieb, Sense About Science volunteer (@Grace_Gottlieb)
Check any newspaper today and you will find advice on what to eat or drink to lose weight or look good. Advertisers exploit our fixation with diet to sell products – from superfoods and “detox” treatments to diet supplements and even this extraordinary weight loss string. Buying into these fads can affect not just your bank balance but, more importantly, your health. So make sure you Ask for Evidence behind claims before believing everything you read.
Trust me, I’m a celebrity…
Many companies use celebrities to sell their products. You have probably seen Vitabiotics adverts where athletes feature with quotes like “Anyone competing or living a healthy lifestyle needs Wellman in their life. I'm a champion and I recommend it.” When Sparkle Ward asked Vitabiotics for evidence, they responded saying that the claims made in their adverts are based on individual testimonies only and not scientific evidence. That’s clearly not a great tagline for selling a product! Companies also promote their products as “natural” and “chemical-free”. Well, “natural” doesn’t necessarily mean safe, and everything is made of chemicals. Apples, for example, contain toxic chemicals which would kill you if taken in a large enough dose.
But it’s “scientifically proven”…
Not everyone buys into celebrity endorsements or the idea that “natural” is best. But advertisers have another tactic up their sleeve – scientific-sounding claims to make you think there’s evidence. Danone yoghurt brand Actimel, for example, was advertised as “scientifically proven to help support your kids’ defences” but the Advertising Standards Authority (ASA) ruled that its evidence “wasn’t good enough to prove the claim”. The ASA can’t stop all misleading claims though, so it’s a good idea to be skeptical when you hear claims like “clinically proven” or “dermatologically tested” – vague terms which tell you nothing about the reliability of the evidence.
Often there is an element of truth to scientific claims, but it is twisted or exaggerated. In a Daily Mirror article on beauty secrets, a co-founder of Lush declared “Getting more honey in your diet is great for the face. It’s good at helping the skin absorb moisture.” It’s true that honey itself absorbs moisture but does eating honey help the skin absorb moisture? I asked Lush for evidence and they replied to say that the Lush co-founder “doesn’t remember saying that” but added that honey is “much easier for our body to digest” than sugar and she “feels that it fuels the muscles for longer”. Would you buy a product if the evidence to back it up was based on someone’s feelings?
Exceptional ingredients – are they special or just trendy?
Lush also told me that “Honey has been used as a skin ointment for over 2000 years”, as if that means it must be good for your skin. (Lead, which is poisonous, has been used in cosmetics since Roman times, but they didn’t mention that.) A lot of fuss is made out of the fact that honey and other products are traditional. For example, the Director of the Honey Research Unit at the University of Waikato in New Zealand has said, “I’m a great believer that if anything is traditional then it works. There may be no rational explanation, but that’s because we haven’t found it”. Flawed reasoning like this is at the core of the craze over Manuka honey, which supposedly has “curative powers” superior to regular honey. This belief is so widespread that manufacturers get away with selling it in small jars priced at £60, and there are even fake Manuka honeys on the market – normal honeys falsely advertised as Manuka so sellers can up the price.
Want to lose weight? Ask for Evidence before buying into fad diet claims
Misrepresenting the science seems to be the basis of all fad diets. Some diets have nothing to do with sound science, such as the clay diet which is said to “remove negative isotopes, helping you detox and stay in shape”. Diets such as this one are so ridiculous that they might as well have been made up. In fact, some are indistinguishable from diets that have just been made up. If you don’t believe it, have a go at the Spoof Diets quiz, which challenges you to spot fad diets from fictional ones – it’s harder than you might expect. So how are you supposed to tell what’s good for you and what to avoid? The answer is to Ask for Evidence. Scientists from the Voice of Young Science network helped us look at the evidence behind 13 diets – fad and fiction – and the results show just how important it is to Ask for Evidence behind claims, especially where your health is concerned.
Posted by Ian Bushfield on 18 July 2014
The Government has known that the official statistics are wrong since the Royal Statistical Society raised the issue in the wake of the 2009 H1N1 pandemic. Since then it’s been bounced around departments until we and charities who use and fund research that is affected by this had to write to the Prime Minister calling for action.
I have been trying to track down a response since we sent the letter a month ago. In that time, I’ve repeatedly called Number 10, Department of Health, Ministry of Justice and Home Office, each of whom have sent it to someone else for a response at least once. Number 10 has most recently tasked the Ministry of Justice with providing a response and told us Number 10 won’t be able to help us anymore. Today, the Ministry of Justice told me that a draft response has just been sent to the Minister’s office for sign off and we could possibly expect a response by early next week.
Of course, I’ve now been told several times that we could expect a response very soon but one has yet to materialise. I’ll believe it when I see it and in the meantime, the official statistics are still wrong.