Large Sample of Students Finds No Link Between Junk Food In School And Obesity: Authors Withheld Study For Two Years

From "STUDY SUGGESTS JUNK FOOD IN SCHOOLS DOESN’T CAUSE WEIGHT GAIN AMONG CHILDREN" in ScienceBlog:

[Jennifer] Van Hook and her coauthor Claire E. Altman, a sociology and demography doctoral student at Pennsylvania State University, used a subsample of 19,450 children who attended school in the same county in both fifth and eighth grades (the 2003-2004 and the 2006-2007 school years).

The authors found that 59.2 percent of fifth graders and 86.3 percent of eighth graders in their study attended schools that sold junk food. But, while there was a significant increase in the percentage of students who attended schools that sold junk food between fifth and eighth grades, there was no rise in the percentage of students who were overweight or obese. In fact, despite the increased availability of junk food, the percentage of students who were overweight or obese actually decreased from fifth grade to eighth grade, from 39.1 percent to 35.4 percent.

The sad part of the study is that the authors withheld the results for two years because it not fit their preconceived notions that junk food sold in schools increases obesity among children.

“We were really surprised by that result and, in fact, we held back from publishing our study for roughly two years because we kept looking for a connection that just wasn’t there,” said Jennifer Van Hook, a Professor of Sociology and Demography at Pennsylvania State University and lead author of the study***...we expected to find a definitive connection between the sale of junk food in middle schools and weight gain among children between fifth and eighth grades. But, our study suggests that—when it comes to weight issues—we need to be looking far beyond schools....