Risk analysis is a widely used tool to understand problems in food safety policy, but it is seldom applied to nutrition policy. We propose that risk analysis be applied more often to inform debates on nutrition policy, and we conduct a risk assessment of the relationship of regular carbonated soft drink (RCSD) consumption in schools and body mass index (BMI) as a case study. Data for RCSD consumption in schools were drawn from three data sets: the Continuing Survey of Food Intake by Individuals 1994–1996, 1998 (CSFII), the National Health and Nutrition Examination Survey 1999–2000 (NHANES), and the National Family Opinion (NFO) WorldGroup Share of Intake Panel (SIP) study. We used the largest relationship between RCSD and BMI that was published by prospective observational studies to characterize the maximum plausible relationship in our study. Consumption of RCSD in schools was low in all three data sets, ranging from 15 g/day in NFO-SIP to 60 g/day in NHANES. There was no relationship between RCSD consumption from all sources and BMI in either the CSFII or the NHANES data. The risk assessment showed no impact on BMI by removing RCSD consumption in school. These findings suggest that focusing adolescent overweight prevention programs on RCSD in schools will not have a significant impact on BMI.