People over-eat because of 3 weird psychological biases

People don't just eat when they're hungry, and they don't stop when they're full.

Psychologists have found a not-so-sweet suite of factors that contribute to over-eating.

Here's a run-down:

Your personality traits matter.

According to a new Swiss study cited by New York Magazine, your eating habits are unknowingly guided by your personality traits.

As in:

• Conscientious people are less likely to eat sugary food.

• Sensitive people are more likely to engage in "emotional eating."

• Extroverted people are more likely to eat out frequently, availing them to larger portions.

If your success as an entrepreneur is largely shaped by your personality, then it's pretty natural that your eating habits will be, too.

People pleasers eat a lot at parties.

There's a name for the kind of person that needs other people to feel comfortable — people pleasers.

The fancy psychological name for it is sociotropy, defined as "a combination of beliefs, behavioral tendencies and attitudes that lead a person to attend to and depend on others for personal satisfaction."

In other words, sociotropic people are constantly seeking approval from others.

As a study lead by Case Western Reserve University psychologist Julie Exline found, those who score high on sociotropy tend to over-eat in social situations to make the people around them feel comfortable.

"They don't want to rock the boat or upset the sense of social harmony," Exline said in a statement.

People mirror each other's eating.

One of the weirder findings in social psychology is that people mirror one another's behavior when they're getting along, from body language to tone of voice to eating. A 2011 study of British young women found that they were more likely to eat "congruently," that is, to take a bite within five seconds of the other person taking a bite. In a 1992 study, 153 adults kept eating diaries for a week — and the amount they ate went up 75% when eating in groups.

So while it may be true that you are what you eat, it might be more accurate to say that you eat like those who you surround yourself with.