Is there truth to the idea that men prefer blue and women like pink? Claudia Hammond investigates, and discovers why these colours matter more than we think.

It’s easy to spot the girls’ section of a children’s clothes shop because most of it is pink. I know a lot of parents who insist that they would like their daughters to wear something different, but pink seems to hold an irresistible allure for them. But is that really true? Is it inevitable that girls are born to grow up to prefer pink?

Various studies have looked at colour preferences in different age groups. In the US most have found that babies and toddlers, whether male or female, are attracted to primary colours such as red and blue. Pink doesn’t feature high on the list, although it is more popular than brown and grey. Some studies of this age group have found blue is favoured, others red, but they rarely find any gender difference.

In 2007, research conducted at Newcastle University in the UK asked adults for their favourite colour. Did most of the women choose pink, or even red? No. The colour which came out top, for both men and women, was blue. But women, on average, rated the reddish shades more highly than the men did.

The authors speculated that this was because hunter-gatherer women traditionally had the job of collecting fruit, so they might be more attuned to reddish shades of berries.

It’s not quite clear why this should influence their likes and dislikes. Perhaps it might lead to improved skills in discrimination between different shades of red, but there’s a missing step in the logic.

Since some red berries are delicious and others are poisonous, why should that make red your favourite colour? If women evolved to prefer red, this should be universal, but a study conducted last year with the Himba people in Namibia found there was no preference for reddish tones among women. Hard-wired colours?

Cultural norms may also shape colour preferences. In cultures where pink is considered the appropriate colour for a baby girl and blue for a baby boy, babies become accustomed from birth to spending time wearing or even surrounded by, those colours. This makes it hard to know whether any preferences expressed later on are hard-wired. But a study from 2011 tried to get closer to discovering what’s going on.

When one-year-old girls and boys were shown pairs of identical objects such as bracelets, pill boxes and picture frames, but with one object pink and another of a second colour, they were no more likely to choose pink than any other colour.

But after the age of two the girls started to like pink and, by four, boys were determined in their rejection of pink. This is the precise time when toddlers start to become aware of their gender, to talk about it and even to look around them to see what defines boy and what defines a girl. But just like adults, even very small children show biases towards their own group.

This group bias was also seen another study where three-to-five-year-olds were given red or blue t-shirts to wear at nursery. For one group, the red and blue t-shirts were constantly referred to, and by the end of three weeks the children liked everything about their own colour group better. And that was just three weeks. Gender becomes a key topic of discussion from early pregnancy onwards.

When we hear the news of the birth of a new baby, there’s just one thing we want to know. Is it a boy or a girl?

You could argue that it doesn’t really matter what colour babies are exposed to the most, but it can even affect the way we, as adults, treat them. There’s one famous study showing that women treated the exact same babies differently depending on whether they were dressed in pink or blue.

If the clothes were blue they assumed it was a boy, played more physical games with them and encouraged them to play with a squeaky hammer, whereas they would gently soothe the baby dressed in pink and choose a doll for them to play with. Pink for boys?

But what about the idea that a century ago little boys were dressed in pink and pink for girls is only a recent fashion? It seems even that might be something of a myth too. Psychology writer Christian Jarrett describes in his new book Great Myths of the Brain, how an Italian psychologist Marco Del Giudice, who tried to find the origins of this idea, could find just four short magazine quotes, describing pink as the colour for boys.

In two of these he believes that perhaps the blue and pink were accidentally swapped around. That seems unlikely to me, but when he searched a database of five million books printed in American or British English from 1800-2000 more convincing was the lack of any mentions of “pink for a boy”, even though from 1890 onwards there were increasing mentions of “pink for a girl”. Even the association of pink with femininity today can backfire if it’s not used in the right way.

Pink is often used for breast cancer campaigns, but researchers at Erasmus University Rotterdam found that when women were shown adverts dominated by the colour pink, they were in fact less likely to think they’d contract breast cancer themselves or to donate money to a cancer charity. The authors don’t believe this was because they hated the colour pink, but because when they were reminded of their gender so overtly, the adverts felt so personally threatening that it set off denial mechanisms.

But there is one way at least in which pink can be useful for both women and men. Back in 2002 researchers in Switzerland who were keen to increase the response rate to surveys, found that printing questionnaires on coloured paper made no difference, unless the paper was pink, in which case 12% more people filled it in.

Colours, it seems, influence our behaviour much more than we realise.