Foods rich in unsaturated fats, such as avocados, nuts and olive oil, have been found to keep the keep hunger pangs at bay.

A new study has demonstrated that this fat, called oleic acid, stimulates the production of a compound called oleoylethanolamide (OEA) that decreases appetite.

Oleic acid is transformed into OEA by cells in the upper region of the small intestine. OEA then finds its way to nerve endings that carry the hunger-curbing message to the brain. There, it activates a brain circuit that increases feelings of fullness. In previous studies, it was found that increasing OEA levels can reduce appetite, produce weight loss and lower blood cholesterol and triglyceride levels.

Nearly 30 percent of Americans are obese, according to the Centers for Disease Control and Prevention, which has declared obesity an epidemic disease.