It is not uncommon for two people that were once romantically involved with one another to get together as friends for the occasional lunch date as a means for catching up.

However, a new study suggests that breaking bread with an ex is more likely to expose the jealous bones of your current love interest than other personal encounters that do not involve food.

Researchers at Cornell University surveyed 79 undergraduates, questioning them about how it would make them feel if the person they were currently dating was to take part in various activities with one of their exes for an hour, including communicating through email, phone, or more personally by getting coffee or a meal at different times of the day.

In addition they asked a secondary group of 74 undergraduates how their “best same-sex friend” would react to the person they were currently dating having outside activities with an ex.

While communicating through email scored as the least threatening form of contact, dinner ranked higher on the potential jealousy charts than lunch, and late-afternoon coffee scored higher than coffee with a past love interest during the late-morning hours.

"For romantic partners left out of a meal, we find a common view that lunch, for example, is not 'just lunch,'" write researchers Kevin Kniffin and Brian Wansink of Cornell University.

While obvious physical effects of food, such as weight gain, are often studied, researchers suggest that their findings contribute to increasing attention on the influence of food on individual and social behavior.

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