Eating together? Simply a matter of adapting

The results are published in the international scientific journal PLoS ONE on 2 February 2012.

The idea that people adjust the amount they eat to fit in with their eating companion is nothing new. However, previous studies into this phenomenon had only examined the way in which the eating behaviour of person A influenced that of person B. Hermans wanted to broaden this one-sided approach. He explains his reason using an example: 'If the two of us eat together, my eating behaviour can influence yours, but your reaction can then also influence my behaviour. It's a perpetual chain of reactions.'

So Hermans and his colleagues studied whether eating companions also adjusted the timing of their bites in line with each other, thereby literally mimicking each other. Seventy female students took part in the study, eating in a replica restaurant where they were served a hot meal together with a female companion they had not met before. Hermans observed their behaviour via a hidden camera, keeping careful track of exactly when each person ate a bite of the meal. He generated a detailed data file of the exact times at which each one of every couple took a bite.

Mimicry

The study showed that both women in every couple tended to synchronise their bites with their eating companion rather than eating at their own pace. This mimicry was three times more prominent at the beginning of the meal than at the end. The results can probably be explained by subconscious mimicry, according to Hermans. Previous research into social influence on eating behaviour has already demonstrated that women adapt their eating behaviour in line with that of familiar and unfamiliar people, and this research set-up may well have reinforced the effect. 'When eating with someone you don't know, mimicking your companion's behaviour can be an important way to make an impression or ingratiate yourself, particularly when just becoming acquainted.

First study

This is the first study proving that people adapt their eating behaviour at a micro-level. Roel Hermans: 'As we only concentrated on female students, colleagues from the same department will now explore whether the same effects are seen among children.' The fact that obesity is becoming an increasingly urgent health threat makes it important to ascertain the impact that the environment has on our eating behaviour. Hermans: 'I think it's important that people realise how their eating behaviour can be influenced without them knowing. They could use this knowledge to help change their eating patterns if need be.'