The rise in wearable devices and the desire to quantify various aspects of everyday activities has provided the opportunity to offer just-in-time triggers to aid in achieving pre-determined goals. While a lot is known about the effectiveness of messaging in marketing efforts, less is known about the effectiveness of these marketing techniques on in-the-moment decision-making. We designed an experiment to determine if a simple solution of using just-in-time persuasive messaging could influence participants' eating habits and what types of messaging could be most effective in this effort. Our solution utilizes a head-mounted display to present health-based messages to users as they make real-time snack choices. We are able show that this method is effective and more feasible than current efforts to influence eating habits.