People on diet know what it's like to maintain dietary and fitness discipline while trying to shed weight. Having dinner with friends could ruin all the hard work: you might be peer-pressured into sharing a high-calorie appetizer, having a bite of their uber starchy main dish, and you'll probably order a sugary drink - because you can't have plain water all night long, right?

New research presented at the Agricultural and Applied Economic Association’s 2013 annual meeting suggests you can actually maintain your social life and lose weight - as long as you choose the right dinner dates. Eating with friends who maintain a healthy diet may encourage you to order something equally good for you.

Researchers from the University of Illinois at Urbana-Champaign and Oklahoma State University studied the orders of 1,459 restaurant customers who didn't know their choices were being monitored. It turns out diners often ordered something from the same category as the people they were eating with. As an added bonus, when more people at their table ordered from the same category as them, they were more likely to be satisfied with their choice.

But what if your very best friends aren't healthy eaters, and you don't totally appreciate the company of your healthy-eating friends? How will you adjust your meals so that you don't eat unhealthily when you're out with them?