A common tactic used by advertisers in weight-loss product ads is to use before/after photos showing significant weight loss by a model. These pictures are often accompanied by other visual cues such as natural ingredients in the hope of adding a sense that the product is a safe way of losing weight. In this study, the impact of visual complexity and visual contrast on audience’s evaluation of an advertised weight-loss product has been examined. The result suggests that attitude toward the product, risk perception, and purchase intention are highly influenced by the interaction of visual complexity and visual contrast. More specifically, the impact of before/after photo is different on past users of dietary supplements in comparison to non-users. In particular, users’ body image perception and satisfaction with the dietary supplements they used before influence the way before/after photos work. Non-users of dietary supplements who are in the market for weight-loss products might find an ad featuring before/after photos more appealing and are more likely to buy the product. The mere inclusion of before/after photos regardless of the real weight loss (15 pounds. vs. 32 pounds) affects the level of risk perception as well as purchase intention, supporting the notion that usage of before and after photos in dietary supplement ads requires further examination and stricter regulation.