New doctor's orders: No earbuds, no music, and no watching TV while eating.

Researchers at Brigham Young University and Colorado State University have found that the noise your food makes while you're eating can have a significant effect on how much food you eat.

The "Crunch Effect," as they call it, suggests you're likely to eat less if you're more conscious of the sound your food makes while you're eating. Therefore, watching loud TV or listening to loud music while eating can mask eating sounds that keep you in check.

A student eats a pretzel while listening to music. A new BYU-CSU study finds that if you mask eating sounds you may eat more. Credit: Jaren Wilkey/BYU Photo

"For the most part, consumers and researchers have overlooked food sound as an important sensory cue in the eating experience," said study coauthor Gina Mohr, an assistant professor of marketing at CSU.

"Sound is typically labeled as the forgotten food sense," adds Ryan Elder, assistant professor of marketing at BYU's Marriott School of Management. "But if people are more focused on the sound the food makes, it could reduce consumption."

To be clear, the researchers are not talking about the sizzle of bacon, the crack of crème brulee or popcorn popping. The effect comes from the sound of mastication: chewing, chomping, crunching.

Elder and Mohr carried out three separate experiments on the effect of that "food sound salience" and found even suggesting people think of eating sounds (through an advertisement) can decrease consumption.

The most fascinating experiment discovered people eat less when the sound of the food is more intense. In that study, participants wore headphones playing either loud or quiet noise while they ate snacks. Researchers found the louder noise masked the sound of chewing and subjects in that group ate more--4 pretzels compared to 2.75 pretzels for the "quiet" group.

"When you mask the sound of consumption, like when you watch TV while eating, you take away one of those senses and it may cause you to eat more than you would normally," Elder said. "The effects many not seem huge--one less pretzel--but over the course of a week, month, or year, it could really add up."

Elder and Mohr said the main takeaway for people should be the idea of mindfulness. In other words, being more mindful of not just the taste and physical appearance of food, but also of the sound it makes can help in "nudge" consumers to eat less.

So next time you eat, pull out your earbuds and tune into the sweet sounds of your food.

The study is newly published in the academic journal Food Quality and Preference.