Anecdotal evidence and aspartame

Posted by Andrew Wadge on December 21st 2007 in Science in Government

As a scientist, I see some sources of evidence as being more powerful than others. For example, published evidence from a double blind, cross-over study, done to best practice and challenged through peer review carries more weight than anecdotal evidence. 

Nonetheless, all evidence is important and none is discounted when the Agency carries out a risk assessment, though it may be weighted according to its source. I have been interested to learn that the National Council of Women of Great Britain discussed the use of anecdotal evidence at its Annual Conference in October this year and adopted a motion to 'urge HMG to acknowledge the importance of anecdotal evidence in decision-making and put in place a system to seek, listen to, record, challenge and if proven act upon anecdotal evidence.
 
Having reproducible evidence and challenging through peer review are fundamental to the scientific process, but the Agency is not only about science.  When we develop advice and make policies -the risk management part of the business - the Agency takes into account a far wider evidence base (individual liberty, regulatory constraints, economic and social consequences and consumers’ appetite for risk).  This second stage is distinct from the scientific process of advocacy and challenge that generates the risk assessment; it's an iterative, consultative process which leads to our Board reaching and making a judgement accountably and in public.
 
I see anecdotal evidence as a trigger for more rigorous scientific studies which will provide reproducible evidence for an independent analysis of the risks.

The Agency has recently been asked how it is going to respond to the anecdotal evidence of adverse reactions to the artificial sweetener aspartame. 

At a recent meeting of the European Food Safety Authority (EFSA) Advisory Forum, I proposed that EFSA should lead a research project to address anecdotal concerns of consumers about the effects of the artificial sweetener aspartame. The idea is that the study would compare reported symptoms and biochemical parameters in a double-blind cross over design in self-selected groups who report that they are sensitive to aspartame compared with control groups.  EFSA responded positively to this suggestion and will arrange a meeting with key member states to discuss this further.
 
I believe that the Agency needs to be clearer about the relative merits of different types of evidence used in the risk assessment process and so I have asked Professor Colin Blakemore, the Chair of the Agency's new General Advisory Committee on Science to consider this in 2008.

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Testing adverse reactions of aspartame

Posted by Anonymous (not verified) on 14/01/2008 - 11:25

As a sufferer of an unpleasant adverse reaction [explosive diarrhoea] if I inadvertently ingest aspartame, I am delighted to read that you have included aspartame and anecdotal evidence as a subject for your blog. A great many other adverse reactions have also been reported and a book written by a doctor called ‘The Aspartame Disease’. However, as an engineer rather than a scientist, my preference would be to collect as much anecdotal evidence as possible and then test its validity directly. A double blind crossover study would need a very large number of participants to ensure a significant result. As there are 60,000,000 people in the UK, if you found just one suffer in 1000 participants in a trial that would imply there were 60,000 sufferers. This raises the question as to how many sufferers there has to be to raise serious concern and remove the substance from all food and drink

As aspartame’s only ‘benefits’ appear to be its low calorie value and financial benefits to its manufacturers, I would suggest any consumer suffering ill effects would be one too many. Is it a coincidence that since the introduction of aspartame the number of obese people and in particular children has risen greatly; do the increased number of sweetened drinks for children make children seek everything sweet? Since aspartame's introduction the number of people suffering from Irritable Bowel Syndrome [IBS] has also risen greatly; is this another coincidence?

Finally - A committee advised that the results of the Ramazzini research project, which showed a dose-related significant increase of cancers in female rats, should be disregarded. One of the reasons for this advice was that the rats had a respiratory infection. It is now possible to buy throat/cough lozenges which contain aspartame to help with respiratory problems in chemists and even sweet shops. Couldn't this be dangerous?

washing turkeys

Posted by Barry Turner (not verified) on 23/12/2007 - 09:51

so if washings not good are you saying not to wash and cook the turkey without?