The purpose of this study was to evaluate the work of Stellman and Garfinkel who speculated, based on epidemiologic data, that users of intense sweeteners are more likely than nonusers to gain weight.We analyzed the study's design and statistical analysis to determine whether the conclusions of Stellman and Garfinkel were supported by the data.Several methodological flaws and inappropriate statistical analyses were identified. These included: use of data from an unrelated study for which they were not intended; failure to correct for bias due to convenience sampling; use of data from a subpopulation without validation; and stratification of subjects by outcome data.Our analysis indicates that the data from the study in question do not allow one to draw conclusions about a relationship between use of intense sweeteners and weight change. Furthermore, data from well-designed clinical trials have shown that aspartame is not associated with weight gain, and when used as part of a balanced deficit diet, can facilitate weight loss.