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Commercial Weight-Loss Programs

By Stephanie F. Yeager, RD, LDN & Christopher D. Still, DO, FACN, FACP

Summer 2008

This article reviews some popular commercial diet programs so you can decide what is right for you, and also will help teach you how to analyze commercial programs. With all of the enticing advertising and attractive claims about quick weight-loss out there, choosing the right weight-loss program can be difficult. Many commercial weight-loss programs can provide short term answers and temporary results to the problem of being affected by excess weight or obesity.

Many commercial diets can be very restrictive for quick results; as weight-loss slows down, it is easy for people to get frustrated and discouraged. Some programs provide low calorie diets and can teach the basics of healthy eating, while others offer expensive pre-packaged meals.

Pre-packaged meals can be appealing because of the ease of choice and convenience. However, when meals are pre-packaged, the basics of nutrition and healthy eating are not learned, weight maintenance becomes difficult and weight regain is often inevitable.

Liquid meal replacement plans, if used for too long, may be harmful because they can cause nutritional deficiencies. Also, these programs are often difficult to stick with for continued weight-loss because of not being able to maintain a “normal lifestyle”. Unfortunately, when normal eating resumes, weight regain often occurs, again, because healthy eating and portion control is not learned through the diet.

Jenny Craig

About the Program
The Jenny Craig program was founded more than 15 years ago and has 800 centers nationwide. It offers frozen or pre-packaged prepared meals to help with portion management and calorie control. This program offers weekly one-on-one nutritional and motivational counseling.

It was developed by registered dietitians and psychologists and tries to focus on lifestyle changes. Another option available is Jenny Direct, an at-home personalized weight-loss program. Materials are delivered to your home, and weekly support consultations are delivered over the phone.

How the Program Works
A typical Jenny Craig program consists of three meals and three snacks per day, which is calorie-controlled based on your height and weight. The breakdown of the diet is about 60 percent carbohydrate, 20 percent from protein and fats. You are required to purchase foods (main dishes) from Jenny Craig for the first phase, which is defined as the first half of your total weight-loss goal. You can work with your diet counselor to incorporate other food groups, such as fruits, vegetables, dairy and grains to your meals.

After the initial phase, you can transition to grocery foods, however, you are required to keep a food diary and work with the diet counselors on food choices.

What’s the Consensus?
Overall, the Jenny Craig diet is a well balanced reduced calorie diet that you can expect to lose about 1-2 pounds per week on. However, some concerns include:

  • Not teaching basics of nutrition in the initial phase – this could perhaps lead to long term weight re-gain.
  • Counselors are not dietitians – as with many commercial programs, they are encouraged to sell products.
  • Cost of the program – although prices can vary, the company says the average cost is about $60-70 per week, which includes entrées and snacks. Other fruits, vegetables, dairy and some grains are purchased in addition from the grocery store. Additional fitness tapes and videos are also available for purchase. Membership options can also be purchased which can cost around $400 for the first month.

About the Program
Nutri/System was founded more than 30 years ago, also offering prepackaged meals and dietary counseling. More recently it has crossed into an almost exclusively online weight-loss program, complete with online counseling and menu planning.

Nutri/System’s most popular and latest nourishment program features meal plans based on low glycemic-index (GI) foods, which are primarily low sugar, low fat, high fiber and high protein foods. The claim with low GI foods is to “help keep your blood sugar levels stable and your metabolism burning strong, so you can burn more fat.”

How the Program Works
Membership in the online weight-loss community is free-of-charge. Newcomers are assigned to a personal weight-loss counselor, who will track their progress and give advice as long as they follow the program. New members also receive a menu plan, a catalog of products, a food diary, a weight chart, an online weekly newsletter and a few other goodies to get them started.

Other services include online bulletin boards, chat room support groups and a free diet analysis. You can and are encouraged to purchase prepackaged entrées and snacks, however it is not mandatory. However, the menu plans incorporate the pre-packaged foods, so meal planning is difficult if you do not purchase the products.

Nutri/System plan encourages three meals and two snacks per day. They offer more than 100 different prepackaged foods to choose from; you can plan your own meals, or you can sign up for the 28-day meal package. As with others, you have to purchase additional fruits, vegetables and dairy products.

What’s the Consensus?
This diet plan, if proper additional fruits, vegetables and dairy products are added, can also be well balanced and calorie controlled. Following this diet and exercise recommendations should result in about a 1-2 pound per week weight-loss. The program does offer free chat rooms and online support which has been shown to be affective for many people.

One concern is the “bad” carb claim with high GI foods is not exactly a true claim. GI scores are based on single foods, i.e. if you eat them one at a time. So in real life, when you are eating a meal, combining foods and cooking foods affects overall GI score or value. Actually, eating a well balanced meal will in essence lower the GI score of a high glycemic food.

Another concern is that the preplanned, packaged meals do not teach good nutrition as no thought is involved, thus leading to lack of learning the essentials to keep the weight off.

The final concern is the cost of the food, following the meal plan costs about $60 dollars per week which does not include the fruits, vegetables and dairy products that must be purchased in addition to the prepackaged foods.

Weight Watchers

About the Program
Weight Watchers was founded in the 1960’s and offers weight-loss guidance and support. The plan emphasizes a well balanced diet and encourages lifestyle changes and exercise. Weight Watchers has come up with multiple plans for dieters, from which they can pick the one that fits their lifestyle more appropriately.

How the Program Works
The flex plan is based on the point system. All food is assigned a certain number of points according to calories, fat and fiber contents. Dieters are assigned a certain number of points to consume in a day based on their body weight and the number of pounds they want to lose. This system teaches that all food can potentially be incorporated into a healthy eating plan as long as the daily point values are not exceeded.

Dieters learn to balance their food choices; they can also trade physical activity for more points. Another option is the Core Plan ® that focuses on healthy foods (whole grains, fruits, vegetables and low-fat protein foods) without the need for tracking points.

Weight Watchers offers and encourages a lot of support, through weekly meetings (private, online or group) and weigh-ins, to give dieters encouragement, help, suggestions and strategies. No foods are forbidden and no foods are required for purchase. Most foods, even restaurant foods, already have points assigned to them which makes keeping track much easier than needing to figure them out on your own.

Food logs are encouraged, which turns off a lot of dieters. But the benefits gained from keeping food logs will, in the long run, “outweigh” the effort it takes to keep them. Long-term weight-loss and maintenance is better achieved as basics of nutrition and balance is taught. Dieters learn that higher fat and calorie foods can be incorporated but do “cost” more points, therefore they must tradeoff the rest of the day or increase exercise to make up for those foods.

What’s the Consensus?
Overall, this diet plan can teach healthy, balanced eating to dieters for a healthy 1-2 pound per week weight-loss. Weight Watchers is most similar to what dietitians would teach (calorie counting) and most healthcare professionals regard it as a standard to measure other commercial programs against.

The support system can facilitate tools and encouragement needed for weight-loss, however, counselors are trained but are not always licensed dietitians. The cost of a membership is about $20 per year, and meetings cost about $10-$15 per week, although many discount packages are often offered and the online version is about the same annual cost. Support online includes chat rooms, message boards, recipe ideas, meal plans and online journaling.

One concern when counting points is that many of the foods that are zero points often can have 60-80 calories in them. If many of these foods are eaten throughout the day that can add up to prevention of weight-loss (especially for smaller older women, or those people with slower metabolisms) because the daily calorie intake is too high.


About the Program
Slim-Fast has been around for more than 25 years and can offer quick weight-loss by substituting typical high calorie meals with a calorie controlled, sweet-tasting fortified meal replacement shake or bar.

The program offers online support with weight, diet and exercise charting, chat rooms with online buddies, chat sessions with registered dietitians, a weekly newsletter, exercise programs and meal planning. Slim-Fast now offers low-carb, optima, easy to digest, high protein and original products.

How the Program Works
The diet plan is centered around two Slim-Fast meal replacements. One meal consists of a Meal-on-the-Go in a can or bar and the other is a Slim-Fast Meal-on-the-Go combined with 200 calories of your favorite healthy foods. The third meal is a “sensible meal” of about 500 calories, with 1/2 of your plate filled with veggies, 1/4 with lean protein (such as chicken without the skin) 1/4 with starch, a salad on the side and fruit for dessert. A snack of 120 calories is offered as well throughout the day. Fruits and vegetables (about 3-5 servings) are encouraged in addition to the meals and snack.

As the dieter approaches their weight maintenance phase, they can incorporate 2 regular “sensible meals” per day, however, little instruction is given to wean from the products and therefore dieters are expected to rely on Slim-Fast products indefinitely for weight maintenance.

What’s the Consensus?
The cost of the shakes are about $1.40 each and the meal replacement bars are about $1.00 each. The main concerns are that dieters are not taught about nutrition basics and realistically are not going to include the Slim-Fast meal replacements forever. Therefore, weight regain may be inevitable. Another concern is the recommended calorie level may be too low for some dieters.

Overall, if followed correctly, total calories do not go below 1,200 per day, and the plan does encourage additional fruits and vegetables leading to more balance than traditional liquid diets.

Meal replacement diets such as Slim-Fast are appealing because of their simplicity and convenience. This could be an option for those dieters who have plateaued in weight-loss or those who need a jump start.

It would be recommended to follow the Slim-Fast plan with a healthcare professional who can help teach how to wean from the shakes and to monitor for potential complications of a fast weight-loss.

Curves diet

About the Program
The Curves diet is through the Curves Weight-Loss and Fitness Program, a franchise of health clubs for women that provides a 30-minute workout including resistance training, aerobics and stretching. The program includes a meal plan, workout, online support and supplement regimen. The claim of following the Curves diet and fitness program will help you slim down and tone your body while resetting your metabolism at a faster calorie-burning rate.

How the Program Works
The Curves diet plan consists of three phases. Each phase consists of six small meals per day.

  • Phase 1 lasts one or two weeks and allows no more than 20 grams of carbohydrate a day.
  • During Phase 2, certain fruits and vegetables and some whole grains are allowed.
  • Once you reach your desired weight, you progress to Phase 3 and no longer follow specific meal plans.

To reset your metabolism once you reach your weight goal, you are instructed to increase your calorie intake to about 2,500 per day. Within a day or two, you will probably gain about 3 pounds. At this point, you go back to Phase 1 diet for one to two days to “burn off the fat.” When you lose weight again, you return to Phase 3.

You are to continue this cycle for a couple of months until you do not gain weight, thus “resetting your metabolism.” The diet claims you may need to return to Phase 1 for one or two days a month to maintain your weight for the long term.

What’s the Consensus?
Overall, the Curves diet and fitness plan will work because the number of calories consumed in the Phase 1 and 2 stages are significantly less than that of which you are burning, thus leading to weight-loss. However, the claim to reset your metabolism is not necessarily an accurate one.

In order to maintain weight while consuming 2,500 calories per day, you must be burning 2,500 calories per day. Because the program has a strong exercise and muscle building component, you can potentially burn 2,500 calories per day. Alternating between the different nutrient deficient phases according to your weight fluctuations is not considered a solution for achieving and maintaining a weight-loss.

Also, dieters are not taught about good nutrition – they are merely following a diet. My suggestion would be to exercise by all means, but try another diet to follow.

Atkins Diet

About the Program
The Atkins Diet is a high-protein, low-carbohydrate diet devised by Dr Robert Atkins. The theory behind the diet is when you cut out carbs, your body burns fat stores to provide energy. As you burn more calories when your body burns fat compared with carbohydrate, and you will lose weight.

Another aspect of the theory is by cutting out carbs, blood sugar levels remain more stable throughout the day, which is thought to prevent overeating.

How the Program Works
There are four phases to the Atkins diet. The initial phase, Induction, limits your intake of total carbohydrate to 20g a day (the recommendation for healthy eating is 250g a day).

The next phase is the Ongoing Weight-loss phase, which allows you to slightly increase your carb intake, by 5g daily for a week at a time until you find your Critical Carbohydrate Level for Losing Weight. This is the maximum amount of carbohydrate you can eat each day to lose between 1 and 3 lb a week. For some people, this may only be 25g carbohydrate, for others it might be 50g.

The third phase, Pre-maintenance, is when you have just 5-10lb left to lose. During this phase, you increase you carb intake by 10g each day for a week at a time. The idea is to slow down your weight-loss to no more than 1lb a week.

The final stage, Lifetime Maintenance, aims to help you maintain your weight by limiting carbs to less than 90g a day.

What’s the Consensus?
Although people can lose considerable amounts of weight in a short period of time following this diet plan, most people are unable to follow it for the long-term because it restricts a vast amount of food groups. Most people tend to regain weight quickly when they are no longer able to stay on the Maintenance phase, which is essentially, low carbohydrates for life.

Initial concerns of following this diet plan are side effects such as bad breath, weakness, tiredness, insomnia, nausea and dizziness. Constipation often occurs because of the avoidance of high-fiber foods such as fruits, vegetables and whole grains. Long-term side effects include increasing risk of heart disease, some types of cancer and nutritional deficiencies because of following an unbalanced diet that is high in fat, particularly saturated fats which are found in meats and cheeses.

Finally, as mentioned with previous diets reviewed, eliminating food groups or macronutrients from your diet is not considered a solution for achieving and maintaining a weight-loss. The bottom line is for it to be a lifelong behavioral change; dieters should learn about good nutrition and its application to daily life instead of just following the diet.


If you are in the market for a diet, you are faced with hundreds of choices, many with claims that sound like exactly what you need. It is important that when you are choosing a diet to help you reach your weight-loss goals, you evaluate them based on one that will work for you, your lifestyle and will help you achieve your goals.

About the Authors:
Christopher D. Still, DO, FACP, FACN, has been studying developments in nutrition support and obesity for nearly a decade. Dr. Still’s interest in weight-loss comes from his personal experiences with obesity. Dr. Still once weighed 365 pounds, and losing the weight was a life and career changing experience. Dr. Still is certified by the American Board of Internal Medicine, the American Board of Nutrition and the American College of Nutrition, among others. He is also a member of the OAC National Board of Directors.

Stephanie F. Yeager, RD, LDN, has been with the Center for Nutrition and Weight Management at Geisinger Health System since 2002. She completed her Bachelor’s in Nutritional Sciences and Exercise Physiology at Penn State University in 2002 and her Dietetic Internship at Geisinger Medical Center in 2004.

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