Earlier studies associated the first year of college with a dramatic increase in body weight, termed the "freshman 15". However, recent studies showed that weight gain might be smaller. The purpose of this review was to evaluate the extent of observed weight/body composition changes, including factors associated with them, among students entering university. Searches were conducted for studies examining weight/body composition changes during freshman semesters. Most studies were not comprehensive in assessing numerous potential causative factors for weight gain. Methods for assessing diet, physical activity, and behavioral factors varied among studies. Weight changes were often not quantified by measures of body composition (lean/fat) to ascertain that changes were limited just to gains in fat mass. Overall, weight changes ranged from 0.7-3.1 kg, but among individuals who gained weight, the range was narrower, 3.1-3.4 kg. There may be specific groups of students with a greater predisposition for weight gain and future research should focus on identifying those groups. © 2009 International Life Sciences Institute.