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I first wrote about the snail facial back in 2015, in response to an article in the Herald on Sunday on that very topic. Today, the fact that there's a story on the very same subject on the Stuff webpage suggests that there is always an appetite for woo (although when I read the story just now, I was happily surprised to see that all the comments so far were very skeptical). So I thought I would rework that original post a trifle. 

Back in 2015 we were told that one could (if one had a sufficiency of funds) already purchase Snail Soap, which contained "snail slime, virgin olive oil, honey and extracts from medicinal plants". The slime component supposedly helped 'beat' wrinkles (what's wrong with a bit of character?) & reduced scarring. The Herald article included the comment that "No one has come back and said it is rubbish or doesn't work," but then, it might be a tad embarassing to have to 'fess up to spending $25/bar on soap that didn't meet one's expectations.

At the time it seemed that the next contribution gastropods had to make to our outer beauty was the snail facial: snails crawl about over your face, leaving their silvery mucus trails behind them. This probably does leave your face feeling a bit tighter, when the trails dry. But saying that "snail facials are believed to be very good" may well be an example of wishful thinking, especially in the absence of supporting data.

Snail slime does contain lectins, which are a class of glycoprotein; the amount & type of this substance vary with the species of snail. (Many years ago now, my Significant Other used to go out collecting them on dewy mornings, so that the lectin could be extracted and analysed.) It also contains other proteins such as collagen & elastin, which probably comes in helpful for the slug species that indulge in balletic aerial s*x at the end of a mucous bungee cord. But as far as I can see the claims that smearing one's face with this slimy mix will encourage skin cells to make more of these proteins lack support. And indeed, quite why putting protein molecules (which are highly unlikely to be absorbed through your skin) on the dead outer surface of your skin would encourage the cells beneath to spring into activity, is not immediately clear.

Lectins are 'sticky' molecules produced by plants (& algae), animals, fungi & prokaryotes, and are involved in communication between cells, defence against pathogens, fertilisation, metastasis of tumours, and appear to generate an inflammatory response (something that's picked up on by various '' sites such as Those from snail slime may have anti-microbial activity, but in absence of actual infection that would not be a burning reason to use it on one's face. And indeed, I think there's need for caution in their use, as it seems that bacteria such as E.coli can survive for quite some time in snail faeces: I'd certainly want to be sure that the snails had been kept long enough to evacuate their bowels prior to crawling over my skin!

I see that ads for the facial products promoted in today's Stuff story (which, were it not for the inclusion of rather negative feedback from some users, would perhaps best be called an advertorial) claim that

[this] highly concentrated essence contains 96% snail mucin, a powerful ingredient known to aid in skin repair, hydration, brightness, and tone.

This is interesting as the actual ingredients list states - with no mention of proportions - 

Snail Secretion Filtrate, Betaine, Butylene Glycol, 1,2-Heandediol, Sodium Hyaluronate, Panthenol, Arginine, Allantoin, Ethyl Hexanediol, Sodium Polyacrylate, Carbomer, Phenoxyethanol.

So no mention of actual mucin (which is actually a class of glycoproteins), and a bunch of other chemicals that are found in a range of skin products... At least in 2018 they don't claim that this elixir contains the chemical known as "Helix Asperia Muller - just as well, really, as there is no such thing. As one Smut Clyde pointed out to me 3 years ago, when he expanded on this very subject. the phrase is actually a typo (?) for the old taxonomic name of the actual garden snail, Helix aspersa (Muller), Muller being the chap who first described it. The species has now apparently been reclassified as Cornu aspersum. I didn't know that, until he told me.

Also - & unsurprisingly - the ad provides no link to research supporting these claims. As it happens there is some preliminary evidence that the stuff might be useful for some types of skin damage (here, for example), but the top Google Scholar links for a search on mucins and skin hydration relate to people's very own mucins, not those from a snail. Adding Helix to the search string produces nothing either, & nor does using Cornu (the current taxonomic name for garden snails). 

I'd like to say I'm shocked, but I'm not. 

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One of the things that's become quite obvious, in the various anti-vax comments that I've followed and responded to on line, is that people with 'alt' views have very firm ideas on what constitutes 'the truth'. And it's not something that mainstream organisations, authorities, or scienceA are seen as offering.

And so (on a new UNICEF New Zealand post) we see:

Blue chimes in (you get the gist),

and really doesn't think UNICEF New Zealand is telling the truth.

And then there's Black, with her accusation of shills and 'paid' science. We've met Black before.

And yet these claims are so far from what all the data tell us (that vaccines are really rather safe, that they've saved probably millions of lives and avoided or reduced a lot of suffering), that you have to wonder, why? Why are these three individuals, and many others like them, so ready not only to write off modern evidence-based medicine, but to believe the pronouncements of The Health Ranger, Joseph Mercola, Andrew Wakefield, Russell Blaylock, and others like them? There's been quite a lot written on this lately, as it's a question that concerns doctors, scientists, educators, and science educators alike. 

Part of the problem probably lies with the ease with which 'fake news' spreads these days. A study just published in Science (Vosoughi, Roy & Aral, 2018) looked at 126,000 'rumour cascades' (the retweeting of ideas & rumours) on Twitter, and found that fake news is more likely to go viral:

Falsehood diffused significantly farther, faster, deeper, and more broadly than the truth in all categories of information

although fake political news travelled fastest & furthest, and

false news was more novel than true news, which suggests that people were more likely to share novel information. Whereas false stories inspired fear, disgust, and surprise in replies, true stories inspired anticipation, sadness, joy, & trust.

The story is also discussed here at The Atlantic.

It's not all down to bots, either: apparently Twitter bots spread true & false tales even-handedly (if bots have hands!); it's the propensity of people to spread the false stuff preferentially that's the problem. (I've seen this in my own FB circle, with some friends being quite uncritical in sharing rumours that a moment's quick fact-checking show to be untrue.) So why these differences? What is it about human judgement that sees falsehoods spread so fast?

Part of the answer may lie in the architecture & connectivity of our brains. This article at The Genetic Literacy Project notes that 

Some people, especially if they are young, will back away from strong beliefs if exposed to the scientific perspective over a long time period. But in some instances, people hold even tighter to their beliefs, when challenged with facts. It's a baffling phenomenon, yet science has come a long way in understanding the underlying brain functions.


certain brain structures ... are less active during rational thinking, and more active while a person maintains irrational beliefs in the face of counter-evidence.

Because these parts of the brain are aslo involved in stress responses, It's been speculated that 

the tendency to hold tightly to beliefs in the face of counter-evidence may be the result of a kind of stress response ... [one that uses a particular neural pathway] to process signals from what the emotional mind perceives as threatening.

This is similar to the ideas discussed here at Debunking Denialism, where it's suggested that some people may believe in conspiracy theories because this helps them make sense of an uncertain & changing world, plus such theories

provide psychologically satisfying answers to ambiguities and allows people to have a comforting, yet faulty, sense of certainty in the face of a lack of information.

Unfortunately these theoriesB also insulate believers from information contradicting their beliefs, allowing them to see others providing that opposing evidence as bought & paid for (see Black above). And the fact that conspiracy theories often generate quite strong, negative, emotions may help explain their spread, as suggested by Vosoughi, Roy, & Aral (2018). 

Another reason why belief in ideas and concepts that run counter to everything science tells us about the world is discussed by Simon Oxenham on the British Psychological Society's Research Digest page. Writing about a recently-published paper, he asks

Could it be the case that knowing that most people doubt a conspiracy actually makes believing it more appealing, by fostering in the believer a sense of being somehow special?

Oxenham describes how the researchers found that if an individual believed in one conspiracy theory (eg that fluoridation is harmful) they were more likely to believe in others (eg that vaccination is also harmful, or that humans have nothing to do with global climate change) - something that Orac has described as 'crank magnetism'. Those surveyed were also asked to rate their own 'need to feel unique', and it seems that this was also correlated with someone's agreement with conspiracy theories - particularly if they believed that a particular theory was a minority opinion. 

Now, as anyone will know who's read the comments threads on any post or FB article about vaccination or fluoridation, these beliefs can be incredibly difficult to change. And yet it's necessary to try, because these beliefs can also be dangerous if they gain wide currency: witness the outbreaks of measles in Europe and in some US states, due to uptake of the idea that vaccines are harmful. Oxenham discusses the findings of two other studies (the originals are here and here): 

popular conspiracy theories may be best dealt with through early education that debunks dangerous conspiracy beliefs before they have the opportunity to take hold in the wild

And that's because these ideas can be very difficulty to counter once they've become established in someone's mind.

It's a big, & daunting, task. 


A and yes, I know! To paraphrase Indiana Jones: [science] is the search for facts, not truth.

B really , hypotheses

S.Vosoughi, D.Roy, & S.Aral (2018) The spread of true and false news online. Science 359 (6380): 1146-1151. doi: 10.1126/science.aap9559

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Back in mid-February, UNICEF NZ posted a piece on the importance of vaccines. Shortly thereafter, the comments thread had been overrun by anti-vaccination pro-disease activists. (I have to say, I'm really impressed with the person who does UNICEF's social media. Talk about grace & dignity under fire!) This seems to happen every time a story about vaccine-preventable disease hits the mainstream &/or social media, and those opposed to vaccination seem willing to push just about any fable to promote their case. (While I have blocked out names here, most of the images are hot-linked to the original comments threads.)

And so we hear that, apparently, measles is a benign disease.

I asked that more than once, but for some reason the information was not forthcoming. Even when phrased thusly (thanks, Paul!):

If sanitation, better nutrition and plumbing was the cause of reduction of incidence of disease ie morbidity (graphs like the one Black presented show a reduction of mortality from disease) then why did sanitation, better nutrition and plumbing have to wait until 1996 to begin to lower the amount of cases of varicella yet in 1960s lowered the cases of measles? Wouldn't you think that if measles was lowered then chickenpox would also be lowered seeing as they are transmitted the same way?

If sanitation, better nutrition and plumbing was the cause of reduction of polio, why did sanitation, better nutrition and plumbing wait until 2006 to reduce the number of cases of rotavirus but forget to reduce the number of cases of norovirus? After all, all three are transmitted identically and yet one disappeared by 1979, the second began disappearing in 2006 and the third is still running rampant.

In fact, it was pretty much crickets all the way on those questions. Perhaps because there isn't really a possible negative response to the evidence that (eg) the introduction of the measles vaccine really did lead to a marked reduction in measles cases. (Better medical care had already seen a reduction in actual deaths - though they still happen today - 90,000, mostly in underdeveloped countries, in 2016.) The data are discussed in this article, but here's the graph from the US.

Image result for measles cases us 1912-2001

But hey, people like Brown "do their own research" & just know that vaccines contain all sorts of nasty stuff.

Sadly, their "research" appears to be lacking.

All this would be laughable if it wasn't such a danger to public health - for the aim of Brown, Black et al is surely to frighten parents into not vaccinating their children. Goodness knows those various claims about vaccine components have been repeatedly debunked (including in an earlier post of mine), and there's no evidence that vaccines cause autism, or cancer (& in fact, the Hep B & HPV vaccines specifically protect against cancer). Plus there are an increasing number of good-quality studies available on the long-term safety & efficacy of vaccines (see here, here, and here for examples.) But, I guess, if your "research" involves watching "Vaxxed: the movie", or frequenting websites such as NaturalNews and, then you might think otherwise.

Also it seems that vaccines are not for the malnourished:

Well, actually:

In fact, Black doubled down on that one:

Not only is this wrong, it's also despicable victim-blaming: she's implying that if only the child's parents had provided whichever vitamins or foodstuffs the child was deficient in, s/he wouldn't have died. I'm sure that would make this child's parents feel really good. Not.

Black also has a thing for one Dr Deisher - however, a much greater blogger than I has explained on multiple occasions what is wrong with the claims shared on that thread by Black:

The thought of vaccines having anything to do with "aborted foetal cells" seems an anathema to them. However, when you drill down into it, the cells we're talking about are stem cells that had their origins in cells derived from foetuses back in the 1960s. These human cell lines are used in the manufacture of Hep A, rubella, chickenpox & shingles vaccines. Even the Catholic Church is not opposed to this use. However, this doesn't stop Dr Deisher & others claiming that any remaining human DNA (derived from the stem cells) that might be in the vaccines can combine with the vaccinated person's DNA & cause all sorts of harm. As Dr Gorski says, the odds of this are truly minute, and no robust data have been presented to support it.

In other words, despite claiming to be 'dealing in the science', Black seems remarkably poorly informed (& doesn't read her own citations):

In this particular case, the study that Black holds up as proving that catching measles is protective against cancer actually involved a patient treated with a measles virus genetically engineered to attack tumour cells. Which is pretty darn cool, actually, although the virotherapy worked for only one person in the clinical trial discussed here. A second study she put forward was published in that top-ranked lower-tier journal, Medical Hypotheses. And it was a speculative model... However, there is good evidence that measles infection actually reduces the immune system's ability to respond to other infections, and that for a number of years.

In fact, Black & her colleagues are rather fond of saying that Blue, Green & others can't provide good-quality studies demonstrating the efficacy of vaccines because those studies don't exist, a claim that can be disproved by finding even one study to the contrary. Thus I can only assume that she's hoping that no-one goes looking, because she's very, very wrong. See here, here, & here, for example. (Mind you, by the logic displayed by Black & her ilk, those studies aren't any good because they're in the mainstream scientific literature, & we all know how corrupt that is </snark>)