Tag Archives: Cancer

Lots of sexual partners is apparently good for you !

5 Nov

Even by the standards of the British media this is a very strange bit of reporting. Last week a number of usually fairly conservative parts of the British press reported on a study suggesting that having more that twenty sexual partners could reduce a males chances of developing prostate cancer !

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Each of these newspaper stories is reporting a paper by Spence, Rousseau and Parent called ‘Sexual partners, sexually transmitted infections, and prostate cancer risk’ published in the journal  Cancer Epidemiology.

As a teaching example, this story has two great things going for it. First, as I’ve previously written about, ‘sex’ stories are a great way of engaging undergraduate students, and second you don’t have to be a urology expert to start demolishing this story. A moments thought about what hypothesis might be being tested here is worthwhile. Initially you might imaging some sort of ‘exercise’ theory, but of course we’re not talking here about frequency of sexual intercourse, but number of sexual partners (one could have had 21 sexual partners and only had sex 21 times, or one sexual partner and sex many hundreds of times !), which leaves me to think that we might be talking about a ‘promiscuous personality’ in some way inoculates against prostate cancer. As you might imagine, what you actually find is only post-hoc theorising about causality !

When you actually delve into the paper itself two things emerge, firstly that the 19% reduction in cancer risk reported in the newspaper stories wasn’t statistically significant, and secondly that the effect reported only appeared with 20+ sexual partners, 19 partners made no difference at all.

As the wonderful NHS Choices websites speculates, you do wonder if this isn’t an example of just recycling the press release, rather than actually reading the original paper, and whether those writing these stories have and ‘science’ knowledge to back up their work. I shall try this out with my students next week, and report back on the impact !

 

More on the benefits (or otherwise) of coffee

13 Jan

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Coffee, or more specifically caffeine, crops up in a lot of places in my teaching. The Daily Mail has a strange obsession with things that cause or prevent cancer, and over the years coffee has been placed in both the ’cause’ and ‘prevent’ categories. Equally, one of my favourite Daily Express headlines ‘Two cups of coffee a day stops Alzheimer” was based solely on a study in mice. It is, however, slightly depressing when this overzealous reporting of caffeine -related stories begins to infect the BBC.

On the 12th Jan 2014 the BBC website reported a story headlines “Caffeine pill ‘could boost memory'”. The story reports a study of 160 participants, whose memory for images, over a 24 hour period, improved when given a 200 milligram caffeine tablet. The study comes from a very reputable source, and I have no reason to doubt the validity of the science involved, but I am intrigued that the BBC’s reporting of the story seem to fall half way between the extremes of the Mail and Express and actually applying some rational thinking. For example, the BBC report includes the line ‘The Johns Hopkins University study involved people who did not regularly eat or drink caffeinated products’, but makes no further comment on why this might be significant. Now, a sample of American participants who don’t drink tea, coffee or cola seems like it might be less that representative.

To give the BBC some credit, they do include ‘a voice of reason’ at the end of the story ( and I really pleased that in this case it was Dr. Ashok Jansari, a colleague from my own department).  Ash rightly points out the potential negative effect of caffeine, but what I find slightly odd about this is the apparent need to ‘contract out’ rational thinking, as if it isn’t something we should expect from the journalists reporting the story. After all you only need to type ‘caffeine’ into the search box of the BBC website to find a whole range of stories about the possible negative effects of caffeine including the idea of a ban on highly caffeinated drinks for under 16s.

All in all, this seems like a nice story to get students thinking rational at science (i.e. what’s the ecological validity of the original study) but also about the reporting of science and the idea that by learning some simple skills they can seemingly do the sort of thinking that BBC journalists seem to be avoiding. It’s also worth noting that ‘caffeine pill could boost memory’ is a story that is likely to be very appealing to students facing exams, and anything that gets across the message that cans of Red Bull may not be the answer to good exams results can only be a good thing 😉

Do tight belts give you throat cancer ?

23 Oct

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On 1st October the Daily Telegraph reported that wearing tight belts increased your risk of throat cancer. Unlike much popular science reporting this looked like a very straight report of a study, in that it explains the methodology of the study , details where it was published and even quotes one of the authors.

The story gets interesting for teaching purposes it you actually go to the original journal article, as it makes no reference to throat cancer ! What the study actually reports is a link between wearing tight belts and developing acid reflux, equally importantly it was only a very small study (24 participants) that ran for only a few days. It appears that the link to cancer came from an interview with one of the lead authors where he mentioned to small increase in cancer risk that acid reflux caused.

This story seems useful in both encouraging students to read original sources, but also makes a good point about how scientists communicate about science. A scientist talking to another scientist about a tiny increase in cancer risk, will come away with the idea that it isn’t much to worry about. One suspects that a member of the public (or worse, a journalist) would come away from such a conservation just with the phrase ‘CANCER RISK’.

Are fish oils good for you or not ???

20 Nov

I was very impressed last week by a story in the Daily Mail finally accepting that fish oils weren’t a magical cure for any number of health problems. This made me think about ways of getting students to understand the reliability of any particular source of information. After all, reading this one article would make you think that the Mail was a useful source !

After a little thought I typed ‘fish oil’ into the search box on the Mail’s home page and came up with a whole range of ‘interesting stories, a selection of which are listed below:

11 September 2012 “Fish oil supplements ‘do NOT cut risk of heart attacks and strokes”

28 July 2012 “Are you hooked on fish oil yet? The natural wonder drug proven to treat a range of conditions”

13 June 2012 “Elderly warned that taking fish oil pills ‘does not prevent brain decline'” 

31 January 2012 “Taking fish oil during pregnancy ‘protects babies from eczema'”

28 February 2012 “New proof daily dose of fish oil does help keep your brain young”

3 January 2012 “Fish oil may hold key to leukaemia cure”

26 October 2011 “Fish oil supplements ‘can slow growth of prostate cancer cells in just four weeks'”

31 May 2011 “Fish oil could curb binge drinking by reducing desire for alcohol”

8 July 2010 “Fish oil may cut breast cancer risk ‘by a third’ 

24 May 2010 “Health news: Why pregnant women should drink more milk, tackle knee pain with sound waves and could fish oil reduce asthma?”

20 January 2010 “Is fish oil the elixir of life ?”

11 August 2009 “Could a fish oil pill add years to your life?”

22 May 2007 “Heart attack victims should take fish oil pill daily”

15 May 2006 “Fish oil ‘boosts pupil performance'”

I’m not particular interested in the research underlying all of this, (If you are there is an excellent chapter on the ‘fish oil and brain power’ story in Ben Goldacre’s book ‘Bad Science’). However this seems like a great illustration that students do not have to be experts in a particular subject to see that fish oils are unlikely to be the cure for all of these ills. It may well be, once all the research has been conducted, that fish oil does have valuable health properties but that is very different from the panacea presented above !

Cherry picking research. Screens of any sort (and Facebook) may be killing you, or at least your children !!!

14 Oct

In my lecture this week I was covering the idea of cherry picking research findings to match a particular view of a research question, as as luck would have it two days before the British press was covered with the ‘news’ that watching TV (or indeed screens of any sort) was seriously damaging children’s health. This story was based on the latest work of Dr. Aric Sigman, who has previously been involved in Putting baby in nursery ‘could raise its risk of heart disease’ and How using Facebook could raise your risk of cancer. I’m particularly interested in the work of Dr. Sigman as he received his PhD from the institution at which I now work (from the same department).

In my lecture I showed the students a TED lecture from Ben Goldacre on the questionable practices of the pharmaceutical industry in cherry picking research results to support there latest product (excellently detailed in his new book ‘Bad Pharma’). I moved on to show them the psychologists could be equally guilty of this, illustrated with the Facebook/cancer story mentioned above. Aric Sigman’s habit of cherry picking the literature has been extensively detailed, but what I find particularly surprising is that he openly admits to selectively reporting evidence to support his own point of view. All of this from someone who’s academic credentials on the surface seem exemplary . Aric Sigman’s own website lists him as a Chartered Biologist, Fellow of the Society of Biology, Chartered Psychologist, Associate Fellow of the British Psychological Society, a recipient of the Chartered Scientist award from the Science Council and a Fellow of the Royal Society of Medicine. Interestingly, true experts in the fields Sigman writes about, such as Dorothy Bishop (Oxford Professor of Developmental Neuropsychology) have regular criticised his writings (but have had little media impact). Indeed, Bishop has written a great piece on how to become a media science expert, where you suspect she may have had Aric Sigman in mind.

On the surface all of this could be quite depressing for someone trying to teach students to think rationally, in that it questions the value of science’s much-revired peer-review process (Sigman’s work has been regularly published in the peer-reviewed ‘The Biologist’. However, as a vehicle for encouraging students to question everything they are presented with even if it comes from a peer-reviewed sources an an apparently highly qualified author, it is second to none.

On a more cheerful note, my lecture did produce one gem that I will recycle for years to come. The Daily Mail’s article suggesting Facebook could raise your risk of cancer has a very interesting addition an the bottom, a button to post the story to Facebook and a counter showing that 4565 readers have ‘liked’ the story on Facebook !

One of my students spotted this particular gem of irony, so perhaps what I am teaching is worthwhile !

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