Burwood, Victoria, Australia/Deakin University -- Scientists believe they may have discovered what causes some people to overeat -- taste. The researchers found that people who do not taste fat in food are more likely to overeat and therefore become obese.

The study adds to the growing body of research linking the taste of fat and obesity -- and fat as a vital contributor to feeling full. The researchers, from Deakin University, found that people who cannot taste fat in food eat significantly more at lunch after having a high fat breakfast than those who can taste fat.

"These results suggest that the ability to taste fat is linked with the fullness experienced from fat," explained Professor Russell Keast, a researcher in sensory science.

"If you do not taste fat or experience the fullness associated with eating fatty food, you are likely to be more hungry and consume more energy after an earlier fatty meal.

"And as we know, over-consumption of foods -- particularly fatty foods -- is associated with people being overweight or obese."

During the study, the participants' sensitivity to fat taste was tested. Then, over four separate days, they ate a high-fat, high-carbohydrate, high-protein breakfast They were then provided with a buffet-style lunch where they ate a variety of foods until comfortably full. The participants' perceived hunger and fullness were then recorded, along with how the amount of calories they consumed.

Keast, whose findings were published in the journal Appetite, said, "It is becoming clear that our ability to taste fat is a factor in the development of obesity.

"We know that people have a taste threshold for fat. Some have a high sensitivity to the taste and are likely to eat less fatty foods, while others are less sensitive and cannot taste fat - and are more likely to overeat fatty foods.

"We now know that [a lack of] sensitivity to fat taste impairs the body's ability to register the fullness signals that would normally come from eating fatty foods.

"The evidence is therefore building that increasing fat taste sensitivity in those who are insensitive is required as one way to address the growing obesity problem."