Sunday, November 14, 2010

Is that your diet I can smell?

If you want to make money from a product for the masses, make it a weightloss aid.

Despite literally squillions of diets available, it appears that there is always room for another one, and the hoards of people, having lost money (but not weight) on a particualr diet, seem more than ready to transfer to the next thing that will present the opportunity of having a slim physique.

Losing weight isn't particularly easy - like most health advice, it broadly falls into "don't eat too much, don't eat crap and take some excercise", and because longlasting results will take 12 months or more, people get disillusioned and wander off looking for a quicker fix to weightloss.

As a result there is a market ready and willing to try any new way you can think of to lose weight. It may be a surprise to know that most of these fall into two categories -

1. Stuff you already know, packaged in a new way.
2. Stuff that requires will-power - i.e. doesn't do anything.
3. Stuff that will cock up your innards in some way while trying to achieve its purpose.

Some are clever enough to fit into two or more of these groups.

I've came across an example which hit the main stream media over the last few months, and I'll leave it up to you to decide which category it goes into.
"Crystals Use Smell to trick you into weightloss"
said the Telegraph in Nov 2010. A clear statement for fact, no room for discussion, cut and dried TRUE.
"The smells that help you to slim"
wrote the Daily Express in 2009, less certainly, but still no room for doubt.
"Can a spoonful of sprinkles help the weight go down?"
asked the Daily Mail in Aug 2009, offering yet another candidate for Dr*T's First Law.
"Smell yourself Well"
offered the Independent in Feb 2010, the headline editor pleasantly missing the point.

(Incidentally, these last THREE offerings were all penned by Hugh Wilson - he seems pretty good at selling dubious 'science' journalism to multiple papers having recently sold the story of how sitting down can make you ill to both the Independent and the Mail.)

The nub of the product is that it has a smell/flavour, you sprinkle it on your food and hey-ho the weight the drops off quicker than you can say "calories in needs to be less than calories out".

The product is called Sensa(R), and works on the idea that if you overstimulate your body with smells and flavour, it will thinks it's already full and your appetite will be reduced. You won't even want to touch that piece of crackling that's been sprinkled with something that makes it smell really good and taste even better.

The chap who is flogging this is Dr Alan Hirsh MD who seems to have qualifications and publications aplenty, and is the Director of the Smell & Taste Treatment and Research Foundation in Chicago. Admittedly, this is an organisation he founded, but nonetheless.

As always, the important point is: evidence. What are the claims? How are those claims tested and proved?

The website proudly claims:
and a graph showing clearly that the 1436-person clinical trial found that people on the Sensa(R) product lost about 35lb whereas the control group lost 2lb.

This is quite a big thing - usually when newspapers pick up a 'science' story, it is centred around a crappy piece of PR puff, with a trial of about 6 people (I'm looking at you, University of Bath) but this looks good.

In order to find out more about the trial, I went searching in all the usual places - Cochrane Library, Clinical etc, but couldn't find any reference to the trial. After spending more time on this than I probably should have, I had a lightbulb realisation - it wasn't a clinical trial, it was a "clinical study". Apparently, clinical studies *sound* like clinical trials, but they're different - from what I can gather - in that the study has not been verified, validated or approved by anyone or body, outside of Hirsch's own establishments.

So, perhaps then, despite the lack of clarity of the trial - sorry, *study* - the results may be published somewhere? Surely a website wouldn't claim it had 'extradordinary clinical results' without publishing somewhere? Of course not - that would be underhand, unscientific and very, very naughty. Dr Hirsh doesn't come across as the type of fellow just to run an unregulated, unvalidated, unapproved clinical trial and not publish the results.

The link on his website takes you directly to where the results are published, and he has listed this on his publication page
Hirsch, A.R. "Use of gustatory stimuli to facilitate weight loss." ATTD Abstracts, 2008, p. 39.

ATTD Abstracts? Not one I know - a little bit of googling yields that it is an abstract for the Advanced Technologies for Treatments of Diabetes Conference in Prague, Feb 2008. You can find and enjoy his abstract here (put Hirsch into the search box) and, from his website, spend some time cocking your head at the poster he presented (pdf).

Just to clarify this, presenting an abstract at a conference is pretty much open for anyone to do. I could make a copy of the Fallen Madonna With The Big Boobies by Van Klump and articulate how it can be used to cure genital warts, and may well have my abstract accepted.

(This is not to do with low standards, but more with allowing freedom of ideas. I accept my warts cure has limited scientific plausability but that's beside the point.)

So when he says he has 'published', he is not being untruthful, more he is (consciously or otherwise) conflating different levels of evidence - one (the abstract) which requires no questioning, no approvals, no testing, no explaining, no demonstration of data, no minimum levels of scientific methodology to name a few, and two (peer-review publishing) which requires many, if not all those things.

(As I repeat often, peer-review is still open to fatal flaws, but it's certainly better than nothing)

So someone has come up with a product, which contains ingredients currently used in food (so no need for pharma-style regulation), has managed to run an uncritical PR-campaign which has been accepted by many of UK's media outlets (with Hugh Wilson pushing his stories through), without ever having had to present even the slightest snippet of reasonable published evidence, despite claiming to have the most "extraordinary clinical results" of any weight loss aid.

How on earth can the system be so screwed up as to allow this to happen?

As far as a product that is sprinkled on food to overstimulate the senses to aid weight loss, I'm pretty sure I know what it smells of.

(Belated h/t to @kashfarooq)


Photo by Boaz Yiftach


  1. Brilliant post - the whole 'clinical studies vs trials' thing is a subtle trick likely to be lost on the bast majority of newspaper editors/readers. Thanks FSM for pedantic nerdy bloggists eh?!

    Right - armed with your advice on how to set up a quack weight-loss programme, I'm off to repackage a well-known laboratory chemical in a will-power-requiring package that squishes you innards - wanna buy some shares?!

  2. Heh, just some actual research:


    Obesity's link to sense of smell

    People who are overweight have a greater sense of smell for food, a study has found.

  3. The trysensa website now has results from an "independent" "study" ("a double-blind, placebo-controlled study conducted by an independent laboratory"). It's worth looking at:

    It is described (in the filename) as an "abstract poster" but what is it an abstract of? Not a paper, but (I'm guessing here) the study data. No information of any kind on the "study" itself. At the minimum I'd say that this is a quite unconventional way to present "scientific" "data." At the maximum I'd say that - oops, I don't think I can say anything that strong on a blog like this...

    There actually are a lot of studies on "nutraceuticals" these days. They are used to cherry pick data for marketing claims. I personally have done quite a few of these studies as principal investigator for a contract research organization (CRO). The sponsor of the study (company that owns the product) always seems to find something positive in the data, even if the conclusions of the CTR (clinical trial report) show no difference from placebo. Then the claim is made that it was found in a clinical study and this legitimizes their product a little so it sells more. Lay people have no idea how to evaluate a neutraceutical and they like to hear the good stuff.

    If you look at the "data" itself at the above link, it too looks pretty fishy if you've done a lot of research. It is even possible that that the "data" was created in someone's head in the drawing of the charts. Do you really believe that the curves of an effective weight loss product would look like this over a 6 month period? Not me.