Amy Joy Lanou of the University of North Carolina at Asheville and Dr. Neal Barnard with the Physicians Committee for Responsible Medicine in Washington evaluated 49 clinical trials from 1966 to 2007 that assessed the effect of milk, dairy products or calcium intake on body weight and body mass index, with or without the use of dieting.

The review, published in the journal Nutrition Reviews, indicated that neither dairy products nor calcium supplements helped people lose weight. Of the 49 clinical trials, 41 showed no effect, two demonstrated weight gain, one showed a lower rate of weight gain and five showed weight loss.

"Our findings demonstrate that increasing dairy product intake does not consistently result in weight or fat loss and may actually have the opposite effect," the review authors said in a statement.