Weight Watchers, Jenny Craig, & Nutrisystem: Wrap Up!

I want to wrap up my series on the Big 3 of commercial weight loss; Weight Watchers, Jenny Craig and Nutrisystem. I would like to do so by providing as much information from studies as I can while still keeping this succinct. First, let me say that long term data on these programs is lacking, but don’t take my word for it:

Many weight loss programmes show short-term success, but long-term data in larger studies are scarce, especially in community settings. Attrition is common and complicates the interpretation of long-term outcomes. [1]

It is interesting that they mention attrition. Is the attrition due to frustration/boredom with the clinical study or is it failure to stick with the dietary program? We don’t know, but I would reason the attrition is due to the feeling of depravation on these low calorie plans.

The best systemic review of studies we have to date is from Johns Hopkins.

At 12 months, Weight Watchers’ participants achieved at least 2.6% greater weight loss than control/education. Jenny Craig resulted in at least 4.9% greater weight loss at 12 months as compared to both control/education and counseling. Nutrisystem participants achieved at least 3.8% greater weight loss at 3 months than control/education or counseling. [2]

Those success rates versus control groups are not that impressive. As I mentioned before, it is hard to find long term data (greater than 12 months). However, there is plenty of anecdotal data that many clients of commercial weight loss programs regain their weight once we start looking at 24, 36 months, etc. post program completion. If you read my article on Weight Watchers specifically, it mentioned that 5 years after starting the program, 84% had regained weight they initially lose and 50% were at the same weight as when they started or worse off.

This weight regain has been confirmed by at least several studies:

Twenty-four-month data suggest that weight lost with Atkins or WW is partially regained over time. [3]

In weight-loss studies the difference in weight between treatments (between Weight Watchers, Rosemary Conley Diet and Fitness Clubs, Slimming World or a NHS group programme) decreases as time passes because most participants regain weight and therefore mean weight-loss curves tend to converge. [4]

Participants in all groups (self help, 12 week Weight Watchers, 52 week Weight Watchers) regained weight between 12 and 24 months. [5]

Now let’s look at very low calorie approaches. “Very Low Calorie” was used specifically in reference to: Health Management Resources (HMR), Medifast, Optifast. These programs come with medical supervision and they are still failing to deliver long term results.

Very low-calorie dietary approaches can achieve substantial short-term weight losses; however, enthusiasm is limited due to potential risks and the lack of evidence supporting sustained long-term weight losses. [2]

These dietary approaches only have data to support short term success. At 12 months (long term as defined in this study), very low-calorie approaches do not work. And no wonder? The calories you ingest on these programs range from 500 to about 1400 maximum, with many iterations of these programs being around 800 calories [6,7,8]. Can anyone say “hunger pangs”?

Why am I talking about HMR, Medifast, and Optifast? Because I feel the poor success rate of these programs is relevant to the Big 3. Granted, the 800 calories you might consume on one of these “very low calorie” approaches is significantly lower than what you would consume on a Big 3 program, but what do you think happens to the person on a Big 3 program who is eating 1200 calories (which is already very low in my opinion) who gets stuck and cannot lose any more weight?

Answer; they reduce calories even further. They were not eating enough to begin with. They are losing muscle and their metabolism is slowing down. Now they make matters worse by continuing to eat less. At least if you are on HMR, Medifast or Optifast you are under medical supervision. But the Big 3 consumer who has reduced their calories to below 1000 does not have the benefit of the watchful eye of a physician.

Why do these programs, and specifically the Big 3 work initially? A high level of structure and support.

It is unsurprising that highly structured programs with in-person social support, such as Weight Watchers and Jenny Craig, seem more effective in the long term than less structured interventions. Nevertheless, even with such programs, weight loss is modest and likely below patients' expectations. [9]

Some studies have actually contradicted the success mentioned above. It was stated earlier in this article that Weight Watchers achieved 2.6% greater weight loss than a control group. However, another study suggested otherwise:

WWO (Weight Watchers Online) produced significantly more weight loss at 3 months relative to Control, but not at 12 months…At 12 months, there were no significant differences between groups in weight loss. [10]

I have my theory on why. The initial structure and support helped to fuel the initial success which is not surprising. However, long term adherence to a low calorie diet is difficult. Many simply cannot handle the cravings of eating such a small amount of food, especially if you are consuming the packaged food that the Big 3 offer, which leave you with nutritional gaps begging to be filled.

Finally, I ask, is it worth it to MAYBE achieve 2.6% greater weight loss than a control group if you are spending $660 over the course of one year to do it? Let’s illustrate with math. If the control group lost 20 pounds, it means that your $660 spent on Weight Watchers help you lose an extra 0.52 pounds. That’s right, a half pound for your money and time.

What about Jenny Craig? You will spend $5400 on their food over the course of a year (easily several thousand more than you would on normal healthy groceries for yourself) and lose one more pound than a control group. Ouch! Over five grand for a one pound difference, not the greatest investment.

Is it worth it? You decide.

What do I think? A picture is worth a thousand words.

If my readers are looking for more input into the pros and cons of these and other popular diet plans of 2020, please consider reading "Top Diet Plans of 2020" over at ConsumersAdvocate.org.

Their review takes into account the scientific literature as well as sustainability. I agree with their approach, if you cannot sustain your diet due to cost, lack of variety, etc then you simply are not going to be successful.

1.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4052429/

2.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4446719/

3.http://circoutcomes.ahajournals.org/content/early/2014/11/11/CIRCOUTCOMES.113.000723

4.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3933848/

5.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5459752/

6.https://health.usnews.com/best-diet/hmr-diet/health-and-nutrition

7.https://health.usnews.com/best-diet/medifast-diet

8.https://www.optifast.com.au/faq

9.https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4845909/

10.https://www.ncbi.nlm.nih.gov/m/pubmed/28437597/