Staff at a primary school in Dundee want to change the colour of the uniform because they think the red colour could affect children’s behaviour. According to the Headmistress Gillian Knox:

‘Red is often used to energise body and mind, and some research indicates that it can increase heart and breathing rates. [This is] not the calm, relaxed learning state we hope to achieve. A recent study linked red to impaired performance on achievement tasks.’

Pupils currently wear a bright red jumper or cardigan with grey trousers or skirt. But teachers want there to be only ‘small amounts’ of red – such as in the school tie.

However, although statements such as this – that red raises heart rates – are all over the red and often cited as facts (as in ‘everybody knows’) in fact there is very little evidence that looking at red can affect heart rates. We ran a study at University of Leeds last year and found no statistically significant effect of the colour of light on subjects’ heart rates or on their blood pressure. A review of the literature reveals little evidence: there is a PhD thesis from California from about 1950 that nobody can get hold off and a study with mentally handicapped children in the 80s. That’s it. Light certainly affects us physiologically but it is far from fact that red raises blood pressure.