Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.


Jenna Carlson

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The World Health Organization (WHO) has declared obesity as a global epidemic, estimating 2.3 billion people will be overweight, and 700 million people will be obese by 2015. With the rise in obesity, weight-loss programs are one avenue that consumers are using to battle the epidemic. Approximately 2/3 of adults in the Western population are trying to lose weight or avoid weight gain.

The purpose of this paper is to review the current research of four major weight-loss programs: Weight Watchers, Jenny Craig, Nutrisystem, and Medifast, regarding fundamentals of the programs, the programs safety for consumers use, effectiveness of the programs short-term, and the long-term results available through studies. Weight Watchers and Jenny Craig have similar concepts with food in moderation and exercise, while Nutrisystem and Medifast, were similar in their use of meal replacements. Research showed that commercial diets like Nutrisystem, Jenny Craig, and Medifast are considered unsafe, due to enabling of unhealthy eating behaviors. Weight Watchers is currently one of the only programs that offers published peer-reviewed evidence of weight-loss effectiveness. Due to the lack of data in regards to long-term studies of effectiveness, Medifast, Jenny Craig, and Nutrisystem, have yet to prove their claims to help consumers keep weight off in the long-term.

Promoting the use of weight-loss programs by registered dietitians is not suggested. It is ideal to help individuals integrate exercise and eating in moderation to maintain a healthy lifestyle, because successful weight-loss requires long-term commitment to healthy eating and exercise habits.