A pox on your detox

Last week on the show, Stu talked about something that catches the attention of many of us who over-indulge during this silliest of seasons: detox. In particular, the detox programs hawked by manufacturers of vitamin supplements and weight-loss plans, which claim to cleanse your body of toxic substances.

These pseudomedicines are a beloved bane of science communicators everywhere, so I don’t really have much to add. Instead, I recommend you listen to our podcast.

But if you really need to read something about it, try the following:

• consumer advocate Choice’s investigation of 10 diet detox products, CHOICE says you don’t need a pill to purify (media release), or Do diet detox products work? (full article).
• British doctor and author of Bad Science Ben Goldacre’s classic take-down of The detox myth (The Guardian)
• another British group, Sense About Science’s comprehensive, 18-page Detox dossier
• academic website The Conversation’s recent feature Monday’s medical myth: detox diets cleanse your body.

But if you really, really want something without having to click a link, take the following example: cigarette smoke.

Cigarette smoke and the damage it causes cannot be cleansed by taking a magic pill. The only way to get it out of your system is to stop smoking for good (Quit poster, Australian Government)

Cigarette smoke is one of the toxins most frequently listed by detox proponents. But as we all should know after decades of government advertising – like the Quit poster shown above – the only way to rid yourself of its toxic effects is to stop smoking.

There is no magic pill, lemon drink, ear candle, or – heaven forfend – colonic irrigation, that will protect you from harm and allow you to keep smoking. Similarly, quitting for a couple of weeks, or 10 days as many of the detox plans seem to run for, won’t undo the damage from years of tobacco.

As for other, less deadly toxins that you consume in moderate amounts – like say, chocolate – well your body is quite capable of handling them itself, thank you very much. You don’t need to swallow another substance to chase them out of your system.

When you think about it, detox programs are a bit like the old lady who swallowed a fly. And look at what happened to her…

Rising antidepressant use may be something to be sad about

According to a new paper, antidepressant use in Australia has doubled in the past decade (Stephenson CP, Karanges E & McGregor IS 2012, “Trends in the utilisation of psychotropic medications in Australia from 2000 to 2011″, Australia & New Zealand Journal of Psychiatry, first published 9 November 2012, doi: 10.1177/0004867412466595).

In fact, over this time there’s been an increase of 58% in the prescription of all psychotropic drugs, even though Australia’s population has only increased by 13% in that time.

Psychotropic drugs are those that affect the brain, and as well as antidepressants they include sedatives, antipsychotics, mood stabilisers and medication for attention-deficit hyperactivity disorder (ADHD).

Pills of the antidepressant fluoxetine, aka Prozac (Photo by Tom Varco, via Wikimedia Commons)

Most of these types have had large increases too. Antipsychotic use has also doubled between 2000 and 2011, ADHD drugs (including methylphenidate) have increased by 73%, and although some benzodiazapines like Valium have remained fairly stable, the newer alprazolam (Xanax) has gone up.

According to one of the authors, Professor Iain McGregor from the University of Sydney’s School of Psychology:

“These results are surprising, somewhat worrying, and raise the question of why so many of us need drugs to be able to cope with modern life.

“The heavy use of antidepressants may reflect their increasing use in conditions other than depression: everything from anxiety disorders to treating pain.

“These drugs have been relentlessly promoted by the pharmaceutical industry but meds are not the only answer, and anyone with emotional problems should consider diet, exercise, lifestyle changes and psychological therapy.”

You can read more about this study at the University of Sydney.

(This story aired on 29 November 2012 – you can listen to the podcast.)

Morgellons mind games

‘Morgellons’ is the popular name for a skin condition that, from scientific evidence, appears similar to delusional parasitosis, i.e. a very strong delusional belief that parasites are crawling under the skin. But just because it’s a delusion doesn’t mean people are making it up, or that it an be cured simply by telling the patient that it’s psychological.

The symptoms are real enough: skin lesions, a feeling of stinging, biting, or pins and needles, and frequently also fatigue, difficulty in concentrating, short-term memory loss and depressed mood. But perhaps the most characteristic feature is the appearance of fibres – often blue or red – or other solid material under the skin.

Examples of Morgellons skin lesions. B and D are close-ups of the sores in A and C respectively. You can see the characteristic blue fibres in each of these (photos by CDC, via PLoS ONE)

It’s relatively new, first ‘identified’ in 2001 by Mary Leitao, whose two-year-old son complained of ‘bugs’ and developed sores with curiously coloured fibres. Disappointed with the lack of medical recognition, she named the condition ‘Morgellons’ after a mention in A Letter to a Friend by Sir Thomas Brown, published in 1690.

Since then, the number of patients reporting similar symptoms – mostly in the United States – grew rapidly, despite lack of formal recognition in the medical community. The level of attention led the US Centers for Disease Control and Prevention (CDC) to conduct a study into what they called ‘unexplained dermopathy’.

The results of this study were published in January 2012, and they reinforced the similarity to delusional parasitosis (Pearson ML, Selby JV, Katz KA, Cantrell V, Braden CR, et al. 2012, “Clinical, epidemiologic, histopathologic and molecular features of an unexplained dermopathy”, PLoS ONE, vol. 7, no. 1, e29908, doi:10.1371/journal.pone.0029908).

The mystery fibres, analysed with light and scanning electron microscopes, X-ray and infrared spectroscopy, turned out to largely be cellulose, consistent with the idea that they came from clothing or bandages – some even with evidence of dyes.

Skin lesions showed evidence of being caused either by scratching or bites (by insects or other arthropods, not humans). And interestingly, those with sores on their backs usually had an unaffected dumbell-shaped area – just where they wouldn’t be able to reach.

There was no sign of any infection by parasites or bacteria, other than those normally found on skin, and there was no consistent evidence of environmental factors through analysis of geographical locations or habits (apart from a finding that most patients had been near some sort of solvent, but the researchers had no comparison with normal prevalence in the community.

What they did find was a high rate of psychiatric conditions, including somatisation (feeling physically ill due to anxiety) and depression, and of illicit drug use. These may not be surprising, given that psychological effects are included in the usual description of Morgellons, and although some drugs can cause delusional parasitosis, it’s not clear here whether that could have happened or whether patients may have used drugs to alleviate their symptoms.

Overall, the researchers couldn’t identify a cause. Based on what they did find, they suggested doctors treat either the individual symptoms, or use treatments recommended for delusional parasitosis (and treatment with anti-psychotic drugs has been tried – see Reid E & Lio PA 2010, “Successful treatment of Morgellons disease with pimozide therapy”, Archives of Dermatology, vol. 146, no. 10, pp. 1191-1193. doi:10.1001/archdermatol.2010.276).

Of course, not everyone agrees with this finding. The spread of Morgellons seems to have been due as much to the Internet as anything else – computer viruses aren’t the only diseases you can catch online.

But remember that even healthy people can have itching induced by visual stimuli. For those experiencing an actual delusion, the symptoms are very real and very painful – the hope is that with this thorough study they can be directed to realistic treatments, rather than the conspiracies so easily found online.

(This story aired on 29 November 2012 – you can listen to the podcast.)

Mental itching is a real head-scratcher

Two recent studies show that an itch can be caused just by watching someone else scratch, or by looking at pictures of itchy things.

The first involved 51 participants watching videos of others scratching, while scanning their brains to see which parts were activated. Interestingly, watching someone else scratch switched on the same areas of the brain as scratching yourself (Holle H, Warne K, Seth AK, Critchley HD & Ward J 2012, “Neural basis of contagious itch and why some people are more prone to it”, Proceedings of the National Academy of Sciences, vol. 109, no. 48, pp. 19816-19821, doi: 10.1073/pnas.1216160109).

It’s tempting to think this is related to empathy, but in fact those most susceptible to induced itching were the more neurotic members of the group. So it appears to have more to do with one’s own hang-ups than an ability to put oneself in others’ shoes.

Bull ant from the genus Myrmecia, found in bushland surrounding Swifts Creek, Victoria – actual size is around 25 millimetres. Are you feeling itchy yet? (Photo by Fir0002/Flagstaffotos)

The second study had 30 participants looking either at itch-related pictures, like ants, fleas or skin conditions, or neutral images, like butterflies or healthy skin. Once again, there was a strong correlation between feelings of itchiness or actual scratching, and the nature of the images (Lloyd DM, Hall E, Hall S & McGlone FP 2012, “Can itch-related visual stimuli alone provoke a scratch response in healthy individuals?”, British Journal of Dermatology, published online 22 November 2012, DOI: 10.1111/bjd.12132).

The researchers of this study concluded that this shows evidence of the involvement of so-called ‘mirror neurons’ – those brain cells that respond equally to performing a task and watching someone else perform the task – but they point out that the fact that only pictures of stimuli were involved, it’s more than just mimicking behaviour.

Either way, it seems that the urge to scratch can be as much a matter of perception as it is of the presence of a genuine irritant.

(This story aired on 29 November 2012 – you can listen to the podcast.)

Asbestos, the Fiend’s fibre

The ABC TV mini-series Devil’s Dust gave an enlightening but frightening history of asbestos-related disease and litigation in Australia, and it made me want to find out more about this wonder material turned bad. What exactly is asbestos, and how does it cause cancer?

Blue asbestos, or crocidolite, mined at Wittenoom, Western Australia. The ruler measure is 1 cm, giving an idea of the tininess of the fibres (Photo by John Hayman, via Wikimedia Commons)

Asbestos is a family of fibrous minerals. The most common type mined in Australia, primarily at Wittenoom WA, was blue asbestos, or crocidolite. Its chemical formula is Na₂Fe²⁺₃Fe³⁺₂Si₈O₂₂(OH)₂, which is actually that of an igneous mineral called riebeckite. Riebeckite forms elongated blue crystals, but it’s only considered asbestos when the crystals are fibres with a width of about 1 micrometre or less.

There are five other types of asbestos, mostly minerals with tiny rigid fibres like crocidolite. However, there’s one kind, known as white asbestos or chrysotile, mined primarily in Canada, which has longer, softer fibres.

All kinds of asbestos are resistant to fire, heat and chemical damage, and have been used in various forms for thousands of years. However, it’s probably the flexible white asbestos, chrysotile, which was woven into miraculous cloths that could be cleaned simply by throwing them into the fire. Wily traders tried to convince people these cloths came from the fur of the fireproof salamander, but Marco Polo himself debunked the idea, calling it “fabulous nonsense”.

In Australia, the less flexible blue asbestos was used for decades as a component in building material and insulation, thanks to its good tensile strength. But there have been other uses that seem absolutely crazy in hindsight, such as making filters for cigarettes and gas masks, or even artificial snow.

Johnny Storm, aka the Human Torch, had the superpower of bursting into flame and so for safety he basically lived and breathed asbestos. Of course, he got his powers through exposure to radiation, so maybe ‘safety’ is subjective. (Strange Tales #101, 1962)

However, health problems due to over-exposure have been known for hundreds of years, with mentions of lung disease afflicting slaves who worked in asbestos mines. Quite possibly this was asbestosis, which is scarring of the lungs caused by an accumulation of inhaled fibres.

Even scarier though is mesothelioma, a cancer of the mesothelium, or protective lining around organs – primarily the pleura, which lines the lungs.

How asbestos causes cancer – or even how it gets out of the lungs and into the pleura – is not exactly known. There are theories that it causes inflammation, or oxidative stress due to the undigestibility of the fibres, or that it interferes with signalling mechanisms, or even that the fibres get physically tangled and interfere with chromosomes in the cell (Toyokuni S 2009, “Mechanisms of asbestos-induced carcinogenesis”, Nagoya Journal of Medical Science, vol. 7, no. 1, pp. 1-10).

This is because one notable property of asbestos fibres is that, even though they start at a scale of around 1 micrometre, they easily break up into into thinner fibres, getting down to 0.01 micrometres, or 10 nanometres. That’s smaller than the pores in cell nuclei.

Whatever the mechanism, it seems that it can only take one rogue asbestos fibre to give you cancer. So should you panic?

Well, although there are about 600 new cases of mesothelioma diagnosed in Australia every year (based on 2007 data), that doesn’t necessarily reflect the ubiquity of asbestos in the community. Some people contract mesothelioma after minimal exposure, such as washing clothes or being near a building site, but some workers in asbestos plants don’t get the disease. It’s possible that most of the fibres are removed by the human body before they’re able to do lasting damage.

That doesn’t mean you should be too complacent, as mesothelioma can take between 20 and 50 years to develop following exposure. But neither should you panic: when the dangers were first realised, there was a rush to remove asbestos from buildings, but this only led to more fibres being released into the air. So now the recommendation is that, if the asbestos is intact, it’s safer to leave it where it is.

But if you are doing renovations and need to remove it, it’s important to follow appropriate safety precautions, or hire a qualified contractor. You can find information about safe removal of asbestos at Asbestoswise, www.asbestoswise.com.au.

Asbestoswise also recommend not panicking if you accidentally disturb and break some asbestos. Their advice is to wipe up the dust with a damp cloth or paper towel, put the cloth or towel into a plastic bag, tie the plastic bag and put it into another plastic bag, tie up that one and put it in your rubbish bin. Seal any cracks in the panel, or if it’s too damaged, replace the whole thing.

So asbestos is very scary, but you don’t need to panic – just treat it with caution.

You can find out more about mesothelioma from the Cancer Council Victoria.

(This story aired on 29 November 2012 – you can listen to the podcast.)

Synaesthesia mixing the senses at MONA

On 3 and 4 November 2012, I was lucky enough to visit Hobart’s Museum of Old and New Art (MONA) and enjoy a two-day event that mixed art and science to explore the psychological phenomenon of synaesthesia.

Synaesthesia is a ‘joining of senses’, where you perceive something with one sense and at the same time you experience it with another sense. For instance, you may see colours and shapes when listening to music, or colours associated with particular letters or numbers.

MONA’s Synaesthesia event represented this concept with the Tasmanian Symphony Orchestra playing music from composers such as György Ligeti, Henryk Górecki and Modest Mussorgsky, as well as performances from Brian Ritchie, Kate Miller-Heidke and Meow Meow. It blended this with visual art from the museum’s exhibitions, a film program, including Jonathan Fowler’s Red Mondays & Gemstone Jalapenos, embedded above, and fantastic catering.

It also included a panel discussion on the topic, with synaesthetes Andrew Legg and Margaret Hollis, pianist and music scholar Peter Hill (representing the synaesthetic composer Olivier Messiaen), and University of New South Wales psychologist Dr Karen Whittingham.

After the discussion, I had the pleasure of speaking to Dr Whittingham about her research on synaesthesia, as well as artist and synaesthete Steve Glass. You can listen to this interview on our podcast from 15.11.2012.

A transcript follows after the break…

More scientists are retracting papers for misconduct

The rate of retractions of scientific papers is rising, being up by a factor of 10 since the 1970s. But a new study shows that this is due more to fraud and misconduct, rather than simple mistakes.

The researchers from Princeton University looked at all 2,047 articles retracted in the field of biomedical and life-science research, as indexed on 3 May 2012 by the US National Library of Medicine’s PubMed service (Fang FC, Steen RG & Casadevall A 2012, “Misconduct accounts for the majority of retracted scientific publications”, Proceedings of the National Academy of Sciences, vol. 109, no. 42, pp. 17028-17033, doi: 10.1073/pnas.1212247109).

They found that only 21.3% of retractions could be attributed to error, with 67.4% being due to misconduct.

‘Misconduct’ here includes fraud or suspected fraud (43.4%), as well as duplicate publication (14.2%) and plagiarism (9.8%).

The rise in retractions has often been put down to pressure to publish leading to mistakes getting through, but the high incidence of fraud suggests that it’s more than mere carelessness.

What’s really concerning is the high rate of citations of these papers, even after they’ve been retracted. Once something is published, there’s no realistic way to control how others use it.

In the long term, these effects may even out. Assuming other researchers follow the scientific method properly, even if they start from a flawed citation their own, rigorous research will correct it. The scientific process will clean things up eventually.

But in the short term, inaccurate research can cause serious problems. An example is Dr Andrew Wakefield’s 1998 study published in The Lancet, which claimed that autism was linked to the measles, mumps and rubella vaccine. Although this was retracted in 2010 and is now considered fraud, it had a huge impact on public perception and gave ammunition to anti-vaccination campaigners.

The most cited article in the study was Dr Andrew Wakefield’s fraudulent 1998 paper that tried to link autism to vaccines, with citations continuing to rise even after retraction (image by Fang et al, PNAS)

In order to keep up with today’s relatively high number of retractions (about 1 in 10,000, compared with 1 in 100,000 in 1977), a website has been created, called Retraction Watch.

If these mistakes can be caught early enough, whether deliberate or not, then it’s hoped that the only damage will be to the reputations scientists involved.

Stretching credulity

Quick news-you-can-use today: the bulk of research shows that stretching before or after exercise doesn’t prevent injury or muscle soreness, or improve performance. In fact, stretching before exercise may increase the risk of injury.

And yes, you should warm up before exercise, but stretching is not a warm-up.

Stretching may feel great – and look impressive – but it won’t prevent injuries or improve athletic performance (Photo by lululemon athletica, via Wikimedia Commons)

Flexibility is one thing that stretching may help, although whether that has any benefits itself is not proven. Its popularity despite lack of evidence leads to the the following curious statement in the 2008 Physical Activity Guidelines for Americans (chapter 4):

“Flexibility is an important part of physical fitness… For this reason, flexibility activities are an appropriate part of a physical activity program, even though they have no known health benefits and it is unclear whether they reduce risk of injury.”

But one thing on which most of us would agree is that stretching feels good. That may be enough motivation itself – after all, it’s probably why animals do it. Just don’t expect other benefits.

For very thorough, exhaustive and well-written further reading, see Quite a Stretch, by Paul Ingraham.

More references after the jump…

I’m looking through you

This month marks the 50th anniversary of The Beatles’ first single, Love me do, and the beginning of their contribution to medical science.

It goes like this: in 1967, Godfrey N. Hounsfield, an engineer working for Electric and Musical Industries Ltd, came up with a way to see soft tissues of the body with X-rays. On a conventional X-ray, bones are much easier to see, with organs like lungs and the brain being only indistinct blurs. But you can get some idea of them by comparing X-rays taken from different sides, like viewing the lungs from the chest and the back.

Hounsfield’s idea was to scan using X-rays from all angles around a person, and then put them together with the aid of computers. This technique came to be called computed tomography, or a CT scan. You’ve probably seen them before: a patient lies on a bed and then an enormous X-ray machine rotates around them. Each scan takes a 2-dimensional slice, and by putting them together it’s possible to build a full, 3-dimensional, even real-time, view of the body’s inner workings.

The first scan by a commercial CT machine was performed on 1 October 1971 in Atkinson Morley Hospital in Wimbledon, England. Eight years later, Hounsfield was awarded the Nobel Prize in Physiology or Medicine for his achievements, sharing it with Allan M. Cormack (Cormack was an American physicist who initially developed a theory of computer-assisted tomography, but his method wasn’t used in the commercial systems).

What does this have to do with The Beatles? Well, Hounsfield’s employer is abbreviated as EMI, which of course was The Beatles’ record label. It was thanks to the gold mine of their musical success – about 200 million singles – that EMI was able to fund Hounsfield’s research over four years to develop his device from a prototype into something that could be used as a hospital.

The Beatles’ music has inspired many people, but their scientific contribution has saved more lives.

References
The Beatles greatest gift… is to science (The Whittington Hospital NHS Trust)
Goodman LR 2010, “The Beatles, the Nobel Prize, and CT scanning of the chest”, Radiologic Clinics of North America, vol. 48, no. 1, pp. 1-7, PMID: 19995626

Sick cities

Older Australians living in urban areas are more likely to have a long-term health problem than those in rural or remote locations, with people from disadvantaged areas faring the worst of all.

Recent research from the University of Sydney looked at the correlation between environmental factors and non-infectious chronic disease in the ageing population using 1,256 survey participants, aged over 45, who had lived in the same location for at least 20 years (Black D, O’Loughlin K, Kendig H & Wilson L 2012, “Cities, environmental stressors, ageing and chronic disease”, Australasian Journal on Ageing, no. 31, pp. 147–151, doi: 10.1111/j.1741-6612.2011.00552.x).

The non-infectious diseases they considered included conditions like type 2 diabetes, arthritis, cancer and asthma, all of which are suspected to be affected by environmental risk factors, or stressors.

Parks and other green spaces in urban areas are believed to be good for the health of our ageing population (photo by Ben Shahn, via Wikimedia Commons)

As lead author Professor Deborah Black said:

“In the city you’re exposed to a range of environmental stressors, such as poor air quality, aircraft and road noise, high density housing, lack of adequate transport, poor urban design, a lack of green spaces and shade trees, and so on.”

“As people get older, their bodies are less able to cope physiologically with environmental stressors, and exposure can accelerate the ageing process and trigger or exacerbate disease.”

Low socioeconomic status was a big factor in this, with those living in the most disadvantaged areas having a 90 per cent greater chance of having a long-term health condition. These areas, with the cheapest housing, are often also near industrial areas, airports or busy roads, and also have reduced access to health services and public transport.

Urban health problems are expected to only worsen with climate change, as the heat island effect causes paved areas to reach higher temperatures, to which the elderly are more susceptible. This suggests that it’s important to try and improve urban environments by maintaining green spaces among the bitumen and concrete.