It used to be thought that blue was an appetite suppressant because blue foods are rare and sometimes poisonous. But I have always doubted this and wrote about it near three years ago on this blog. And then nearly two years ago I posted about research from the University of Basel (Switzerland) and the University of Mannheim (Germany) in which it was shown that participants drank less from a red cup than a blue cup and ate less snack food from a red plate than from a blue plate. In other words, the opposite of what was commonly believed. Today I read in CNN about work by Nicola Bruno, a cognitive psychologist from the University of Parma, about his research to measure how much food or hand cream people used when presented on plates of different colours (red, white or blue). The food and hand cream was available to be used freely whilst participants took part in a survey. People ate less food and used less hand cream when either was presented on a red plate. However, the authors note that in their experiment the participants were unaware of the experiment – so it is not so straight forward to extrapolate and conclude that if you buy red plates for home you would eat less. Because then you would be conscious of the idea and it might not work. On the other hand, it might!!
It was nice for me to hear this story and it reminded me of when Nicola came to visit me (when I worked at Keele University) and we published a paper together. That was in about 2000 and I don’t think I have seen him since. Sometimes it isn’t a small world. But it was nice to come across him again anyway.
Yesterday was the first lecture in my module (Colour: Art and Science) at the University of Leeds. In this module I look at colour from a multi-disciplinary perspective covering art, design, physics, history, philosophy, neuroscience, advertising and branding – all perspectives that are needed to understand colour or are strongly influenced by colour. Towards the end of the module I look at colour in branding and advertising and look at the effects that colours have on people’s behaviours and emotional states. One of the frustrating things about it though is that there is a lack of high-quality research about this. In fact, I would go so far as to say that there is more nonesense written about colour (in books and on the internet) than almost any other topic I know!
Take the effect of colour on appetite. Lots of websites and books will tell you the same thing. Red stimulates appetite and this is one reason, for example, why it might be used in MacDonalds’ interior colour scheme. On the hand, blue inhibits your appetite; one reason for this is often stated as being that blue foods are quite rare and therefore we are predisposed to not want to eat blue foods (though what about blueberries!!). But when people write this, how many of them have actually done any research or read any research about these effects? That’s what I mean about nonesense; people write it because they heard it somewhere or imagined that it might be true. Last week I came across some research on the effect of colour on appetite. In this research, published in the Journal of Appetite, and jointly carried out by staff from the University of Basel (Switzerland) and the University of Mannheim (Germany) it was shown that participants drank less from a red cup than a blue cup and ate less snack food from a red plate than from a blue plate. In other words, the opposite of what is commonly believed. The point of this is that more serious research needs to be done to explore the effects that colour has; come and do a PhD in my lab and help to rectify that!!
Of course, the research referred to above does not necessarily mean that people would prefer red food to blue food or that people would eat less food in a restaurant decorated in red rather than blue. It is exactly that sort of extrapolation that is partly responsible for all of the misinformation about colour that is everywhere around us. I have to confess that I myself am sometimes responsible for this misinformation since I was talking to the students last year about the appetite-suppressant properties of blue. I need to stop now …. and go and do some more research.