If you’re about to begin a weight loss program, it’s wise to wonder which one works best. But you may be surprised to learn that it’s rare for popular diet programs to promote their true, average results.
Most diet programs and products rely on the spokesperson approach, in which a single person’s success story is highlighted to taught the program’s effectiveness. The marketing of a typical weight loss program then centers around that individual case. But “average” results, or statistical studies are hard to come by.
With so much riding on a diet program’s success, it leaves you wondering why diet programs and products don’t do many studies. Unfortunately, it’s looking more like the reasons are because the results are less than impressive. Of the clinical studies we found from a variety of research journals, some diets seem to maintain only a precious few pounds of weight loss results after one or two years.
It takes some advanced searching to find evidence about how well certain diets work, but there are some statistics out there. We’ll cover a few sources for you here.
One of the diet programs that reports statistics is Weight Watchers. This is likely because participants weigh-in as part of the program. Gathering data that is statistically valid, and can stand up to the regimen required for accurate reporting is easier when your whole program is built around weigh-ins that happen in person.
A study published in the British Medical Journal in May of 2006 compared the effectiveness of four popular diet programs, Atkins, Weight Watchers, SlimFast and Rosemary Conley (a popular U.K. diet guru). After eight weeks, participants in the Weight Watchers group lost an average of 2.16 inches in waist measurement, those on Atkins lost an average 2.63 inches in their waists, SlimFast users lost an average of 1.88 inches in waist measurement, and Rosemary Conley dieters lost 1.77 inches.
Zburn, a fat-burning product from Zonital International, was tested in a pilot study by the firm, and users lost an average of 2.5 inches in their waists in two weeks. Considering the British study of diets produced smaller results in eight weeks versus two, the pilot study proved promising. The Zburn study also measured dieters in hips, chest, neck, arms and thighs in addition to their waists.
The FDA and CDC consider “healthy” weight loss to be a loss of 1 to 2 pounds per week. Zburn produced healthy weight loss for participants, as did some of the diets in the British study, including Weight Watchers, Atkins, and SlimFast.
Muscle weighs more than fat, so in measuring diet results, changes in body circumference may be more helpful in determining success of a program, especially if the participant is exercising.
In February of 2006, a study reported in the New England Journal of Medicine, compared low car and high protein diets, with low fat diets, and higher carb versions. The study did not compare branded commercial programs, just the different types of diet structures. The study’s conclusion was that “reduced-calorie” were what made the difference and created, “meaningful weight loss” regardless of the type of food and nutrient focus.
Taking into account info from a study published in the American Journal of Clinical Nutrition, June 2007, the Daily Beast website ranked Volumetrics as #1 in effectiveness. The Volumetrics eating plan features lots of fruits and veggies, or food with high water volume content, giving these foods more “volume” and making the diet seem more filling.
A study reported on CBS news, and published in the Annals of Internal Medicine January 4, 2005, confirmed the overall consensus; that diet product success statistics are rare, and the results which can be confirmed are disappointing, if you have visions of famous spokespeople’s results in your heads. Average weight loss on Weight Watchers may surprise you. The study concluded there is documentation that Weight Watchers participants lost on average, around 5 percent of their initial weight (or about 10 pounds), in six months and kept off about half of it two years later. As for other popular diet plans, there was simply not enough verifiable data.
A study by the American Dietetic Association published October 2007, ranked the nutritional value of 10 popular diets. This study ranked Ornish, Weight Watchers High Carbohydrate, and New Glucose Revolution as numbers one, two and three, respectively. These rankings were for nutritional content, however, and not ranking for weight loss success.
Besides Weight Watchers reports, and the Zburn study, there aren’t many commercial diet products or plans that create their own studies or report others’ results about their average success rates. Today, the FTC requires diet plans which use a celebrity spokesperson in their marketing to disclose “typical” results for average dieters. You may be surprised to see the huge difference between the spokesperson’s weight loss and what is typical. These disclosures are still hard to find. Look in the faded small print of ads when you’re seeking out those numbers.
Since weight loss programs and products may be in updated research continually, you can use search engines to find new studies on your own, by searching terms including the diet name, combined with terms or phrases like, research studies, or published research studies.
