Do you eat snacks habitually at night without being hungry and without giving it a second thought?

According to Brian Wansink, PhD, food psychologist at Cornell University, subconscious eating can lead to avoidable weight gain.

The findings were presented at the Annual Convention of the American Psychological Association.

"Most of us have too much chaos going on in our lives to consciously focus on every bite we eat, and then ask ourselves if we're full. The secret is to change your environment so it works for you rather than against you," Wansink said in an APA statement.

His study indicates that what we see, rather than our stomachs, really does control how much we end up eating.

One of his studies revealed that after making few environmental changes, people lost weight at a rate of up to two pounds a month.

These small changes included using smaller salad plates instead of large dinner plates. Keeping unhealthy foods out of sight and keeping healthier foods in more visible places, especially in the refrigerator. Lastly, another change included eating in the kitchen or dining room rather than eating while watching television.

"These simple strategies are far more likely to succeed than willpower alone," said Wansink. "It's easier to change your environment than to change your mind."

In one of his experiments, 30 people were given soup out of a "bottomless bowl" that was pressure-fed under the table and slowly refilled from the bottom without them realizing it. Another 30 people were served soup in regular bowls.

Results revealed that those with the "bottomless bowls" ate 73-percent more than those with the normal bowls. However, the "bottomless bowl" participants didn't realize they had eaten more.

"Don't rely on your stomach to tell you when you're full. It can lie," Wansink says.