This study explored the role of life events in triggering both weight loss and weight gain and assessed whether a number of variables differentiated between these two types of weight change. Members of a slimming club (n = 538) completed an online questionnaire concerning two events, which had caused either weight loss or weight gain. They then described the event and its impact in terms of a number of variables. The majority of participants could describe a time when a life event had resulted in both weight loss and weight gain including relationship problems, pregnancy, illness and death of someone close. Compared with the weight gain event, the weight loss event was perceived as more positive, less negative, more controllable and more predictable than the weight gain event. Further, in terms of sustaining conditions, the weight loss event was perceived as reducing the choice over food and the function of eating and as increasing the choice over exercise and the function of this behaviour. To conclude, life events are related to weight change and the direction of this change can be explained both by the perceived nature of the event and its impact upon choice and function of eating and exercise.