Understanding the degree to which eating behaviors, such as disinhibition and restraint, are associated with weight loss and weight loss maintenance could contribute to further refinement of effective weight management intervention strategies. The purpose of this analysis was to examine if these factors mediate weight loss or weight loss maintenance using data from a randomized controlled trial testing a commercial weight loss program that delivered behavioral counseling and structured meal plans including prepackaged foods. Mediation analyses were used to examine whether changes in disinhibition and restraint mediated the relationship between intervention and weight change during initial weight loss (0-6 months), continued weight loss (6-12 months), or weight loss maintenance (12-24 months) phases. Only decreases in disinhibition between baseline and 6 months mediated the intervention effect on initial weight loss. Our results suggest the mediation effects of these eating behaviors are modest and other factors contribute to a larger, more complex long-term weight loss prognosis.