Washington, Sep 2 (IANS): Do you always snack on while watching TV or munch popcorn at the movie theatre? Blame it on your bad eating habits.

A new study explains how and why such habits prevail even when the stuff we're eating doesn't taste half as good.

Researchers gave people a bucket of either just-popped, fresh popcorn or stale, week-old popcorn, before they entered a movie theatre, the journal Personality and Social Psychology Bulletin reports.

Moviegoers who didn't usually eat popcorn at the theatre ate much less stale popcorn than fresh popcorn. The week-old popcorn just didn't taste as good, according University of Southern California statement.

But typical popcorn addicts among movie goers ate about the same quantity of fresh or stale popcorn. In other words, it made no difference whether the popcorn tasted good or bad.

"When we've repeatedly eaten a particular food in a particular environment, our brain comes to associate the food with that environment and make us keep eating as long as those environmental cues are present," said David Neal.

Neal was psychology professor at University of Southern California when he conducted the research. He now heads a social and consumer research firm.

"Nobody likes cold, spongy, week-old popcorn," said study co-author Wendy Wood, provost professor of psychology and business at Southern California.

"But once we've formed an eating habit, we no longer care whether the food tastes good. We'll eat exactly the same amount, whether it's fresh or stale," Wood added.