Along with the size of your waiter, the lighting, music, and even where you sit has been shown to unknowingly bias what you order.
The amount of food you order at a restaurant may depend on how heavy your waiter is, a new study suggests.
The study of 497 diners in 60 restaurants showed that diners who ordered their dinner from heavier wait staff were four times more likely to order dessert, and ordered 17 per cent more alcohol.
"No one goes to a restaurant to start a diet. As a result, we are tremendously susceptible to cues that give us a license to order and eat what we want," said lead author Tim Doering, researcher at the Cornell University's Food and Brand Lab.
"A fun, happy, heavy waiter, might lead a diner to cut loose a little," said Mr Doering.
The study observed 497 diners ordering dinner in casual American restaurants. It then compared these orders to the Body Mass Index (BMI) of the person who waited on them and the size of the diner.
"A heavy waiter or waitress seems to have an even bigger influence on the skinniest diners," said Mr Doering.
Along with the size of your waiter, the lighting, music, and even where you sit has been shown to unknowingly bias what you order.
Although, you cannot change your waiter or the music in a restaurant, you can follow a personal ordering rule-of-thumb, the researchers said.
"Deciding that you'll have either an appetiser or a dessert - but not both - before you get to the restaurant could be one of your best diet defences," said Brian Wansink, Director of the Cornell Food and Brand Lab.
The study was published in the journal Environment and Behaviour.