The commercial sector, through a range of products and services, is already heavily involved in the weight loss industry. Because of its capability to access millions of people, it has great potential for promoting public health through dietary and exercise practices. However, an absence of controls or advertising standards, safety and quality, currently threatens its credibility. This paper draws from my own experience developing a now well-established diet and fitness organisation. It makes the case that the best quality products and practice arise from close collaboration with scientific experts in the field. Effectiveness is increased through the distribution of sound educational messages, through an array of commercial options that include books, magazines, videos, television and diet and exercise clubs.