Researchers stating the bleeding obvious

In a not unexpected development, newly published research suggests that people who fail to dry their hands properly after washing them may be more likely to spread disease-causing bacteria.

The researchers say that paper towels are the best way to reduce bacterial numbers when drying hands. Dr.Anna Snelling, one of the papers authors, says: "Good hand hygiene should include drying hands thoroughly and not just washing. The most hygienic method of drying hands is using paper towels or using a hand dryer which doesn't require rubbing your hands together".

No doubt this came as good news to the company that funded the research: Dyson Limited, who produce the Airblade, a dryer which uses air 'blades' to strip water from still hands. The paper found that the Airblade was "superior to the warm air dryers for reducing bacterial transfer."

The researchers quantified the effects of hand drying by measuring the number of bacteria on different parts of the hands before and after different drying methods. Volunteers were asked to wash their hands and place them onto contact plates which were then incubated to measure bacterial growth. The volunteers were then asked to dry their hands using either hand towels or one of three hand dryers, with or without rubbing their hands together, and levels of bacteria were re-measured.

However, the results also suggest that "if people use conventional warm air hand dryers for at least 30 seconds, then it is likely that the hygiene benefit will be similar to that achieved with 10 s use of the Dyson Airblade"

Expecting conventional dryers to function effectively using the reduced drying time for the Airblade is hardly reasonable. Obviously, if equipment is not used as designed, it will not function effectively.

Expecting the conventional dryers to work using a 10 second drying time, just because Dyson's latest gadget does is missing the point. When used for the recommended duration, the conventional dryers worked just as well as the new product.

When the A5 and Turbodry (the two conventional driers used in the study) were used for their recommended times of 30 and 35 seconds respectively, there was no significant difference in mean log bacterial count numbers compared to the that present when the Airblade was used for 10 seconds.

The work carried out at the University of Bradford also found that rubbing hands together while using traditional hand driers could actually increase bacterial numbers by bringing bacteria to the surface that usually reside within the skin. These bacteria can then be transferred to other surfaces.

However, this study used a drying time of 15 seconds for all dryers, significantly less than that recommended by the manufacturers of the conventional dryers.

What this paper has shown is that the Airblade does its job effectively in a relatively short duration of 10 seconds. But, what it also shows is that if you use a device incorrectly it won't work properly. That's hardly surprising, is it?

The paper is here.

Probiotic Advert Banned

Following up on my earlier post regarding European Commission findings on probiotic yoghurts and drinks, the BBC report that the Advertising Standards Agency in Britain have banned a TV advert for Actimel - a well known brand of probiotic drinks.

Read the report here from the BBC.

Probiotic drinks under scrutiny

A panel of scientists at the European Food Safety Agency (EFSA) has dismissed a range of health claims made by manufacturers of so-called "probiotic" yoghurts and drinks.
The opinion delivered by the EFSA was part of a wider study of over 4,000 'general function' claims submitted by EU member states. While only about 500 claims have been studied in this batch, the rest are still being evaluated.
A 'general function' claim is a claim made about a particular food product which suggests that it can aid growth, development or function of the body or make you less hungry so that you will eat less, etc. Basically, its the sort of claim made about products that says, 'Eat this and you'll get thin', or 'Eat this and you'll never get a cold or runny nose again'.
Of the 523 claims made about a variety of food components, including probiotic bacteria, one third were upheld as there was a sufficient amount and quality of scientific evidence to back up the claims.
Of the remaining two thirds which were not upheld, over 50% were rejected owing to a lack of information on the substance on which the claim was based.
180 claims made for probiotic cultures were assessed by the panel, with ten claims being rejected outright and the remainder falling into the category where not enough evidence had been provided to support the claims.
Prof. Albert Flynn of the EFSA commented:"EFSA’s independent scientific advice will help ensure that the health claims made on foods are accurate and helpful to consumers in making healthy diet choices. The scientific opinions will inform future decisions of the Commission and Member States concerning the authorisation of health claims”.
As these were "general function" claims, the next phase will be to assess specific claims made and submitted by manufacturers such as Yakult and Danone about specific strains of probiotic bacteria. A spokesperson for Yakult said: "Yakult has submitted claims for Lactobacillus casei Shirota, a well characterised probiotic strain unique to Yakult. Evidence for its health benefit is based on over 70 human studies and over 70 years of research."
Incidentally, and for a bit of fun, you can generate your own probiotic culture name by following the link below and inserting your last name. Enjoy!
http://nfitz.net/probioticgenerator.php