Shining a blue light over a man’s dinner makes him eat less, researchers find

Study says women are not affected by the light, however

A first-person view of someone eating a hamburger (Getty Images)

Shining a blue light over your dinner could make you eat less – if you’re a man, researchers have found.

A study published in the scientific journal Appetite found that lighting food with a blue coloured light “significantly” decreased how much of it men ate.

There was no effect on women who participated in the study, however.

The reason for the change in behaviour appears to be that the food looks less delicious with a blue light shone on it – what the researchers called the “hedonic impression of the food’s appearance”.

“Since naturally blue-coloured foods are rare, humans may have a doubt as to whether they are safe to eat,” they said.

Researchers hypothesised that the difference in reaction between men and women to the light was because women have a better sense of smell – meaning men are “more dependent on visual cues” when deciding whether to eat something or not.

The scientists noted that it did not affect the “willingness to eat” by the men or its perceived flavour.

“This study provides empirical evidence that the colour of lighting can modulate the meal size,” the researchers said. “In particular, blue lighting can decrease the amount of food eaten in men without reducing their acceptability of the food.”

To conduct the study, researchers took 112 adults and asked them to abstain from food the night before.

The participants were seated in booths lit by white, blue and yellow lights and were given a large breakfast of omelettes and pancakes.

After eating as much of the food as they wanted, the participants filled out a questionnaire, from which results were derived.

The results could have implications for combating obesity.

The study was produced by researchers at the University of Arkansas in the United States. The group of scientists who conducted the study was led by assistant professor Han-Seok Seo.