Richard S. Osbaldiston
The obesity epidemic has lead to myriad physical and mental health problems. Correspondingly, the weight loss industry promotes a wide array of products that are marketed to help people lose weight, including glamorous images of impressive weight loss. None of these marketing messages report scientific studies, so we set out to examine the weight loss literature and determine how much weight loss can be reasonably expected and what are the components of the most effective weight loss programs. Using PsycInfo, we located 54 scientific studies in which weight loss was the dependent variable and which reported pre- and post-program weights. We found that, on average, these scientific studies report a weight loss of 11.5 pounds. The most common measurement interval was 6 months, and, on average, participants in these studies lost 9.95 pounds after 6 months. We concluded that the marketing materials for commercial weight loss programs grossly over-report what reasonable results are for these programs.