Consumption of two foods -- nuts and yogurt -- were most closely correlated with weight loss, according to Walter Willett, one of the study's co-authors. Interviewed on National Public Radio, Willett noted that the active probiotic cultures in yogurt may be responsible for yogurt's weight loss powers. "There has been a lot of work in recent years on how the types of bacteria in our colon influence our state of inflammation and weight gain. So it may well be that the healthy bacteria in the yogurt are helping change the mix of bacteria in the colon and influencing weight."

Willett also noted that fat content in foods did not mean that the food itself was fattening. "But eating foods that keep us satisfied is really going to be important in the long run."

From the July 25, 2011, Prepared Foods' Daily News.