Are You a 'People Pleaser'? (They're More Likely to Snack)

"If you sense that another person wants you to eat, you'll be more likely to eat more," Julie Exline, a psychologist at Case Western Reserve University and lead author of the new study published in the Journal of Social and Clinical Psychology, told ABC News.

Social situations are tempting enough when it comes to eating, but some people eat even more to avoid "rocking the boat," Exline said, pointing out that people seem less sociable when they watch their diet, according to previous studies.

But eating a third slice of pizza just to fit in is a decision you might regret later on. "If we look back later and feel like we've given into social pressure, we often regret those choices," Exline told ABC News.

The bottom line: You might want to think about how many extra calories you're taking in as a result of peer pressure. But Super Bowl Sunday isn't really the best time to start cutting back. "If you eat healthy most of the time, it's OK to relax and have fun Super Bowl Sunday," Dr. David Katz, director of the Yale University Prevention Research Center, told ABC.