Nearly half of Americans want to lose weight, yet less than a quarter of adults are seriously trying, perhaps due to the failure rates attached to certain weight loss programs. But why do most adults end up failing? A new study out of Johns Hopkins University suggests many of these programs don't consider reliable, science-based treatments.

"The nutrition and weight loss industry is like the Wild West," said the study’s lead author Dr. Kimberly Gudzune, an assistant professor of medicine and a weight loss specialist at Johns Hopkins University School of Medicine, in a press release. "There is very little oversight, and it's hard for consumers and medical professionals alike to tell what is effective, reliable and meets guidelines' standards."

For the study, published in the journal Obesity, researchers evaluated nearly 200 weight loss programs within a 10-mile radius of 17 different primary care clinics in Maryland, Washington, D.C., and Virginia. They looked at how the programs were advertised, whether they were supervised by physicians, whether they were affiliated with a national brand such as Weight Watchers or Jenny Craig, and whether they were connected to bariatric surgery programs.

Only 9 percent of the programs evaluated followed expert medical guidelines for weight loss issued by the American Heart Association, American College of Cardiology, or The Obesity Society. And only 17 percent of the “high-intensity” programs qualified as high-intensity — standard high intensity programs involve 14 sessions within a six-month period. While most of the programs, 57 percent, described increased physical activity as part of the regimen, only 3 percent of the programs included the recommended 150 minutes or more of moderate physical activity a week.

When it came to nutrition, 75 percent of the programs described a dietary change as part of their weight loss plan, but no official nutrition plan was outlined. Instead, 34 percent of the programs endorsed supplements for weight loss, like vitamins, minerals, herbal, botanicals, amino acids, enzymes, and hormones. What’s more, 15 percent of programs reported prescribing weight loss medications, like phentermine, topiramate, lorcaserin, and orlistat approved by the U.S. Food and Drug Administration (FDA). Researchers point out most vitamins, minerals, and herbal supplements lack any scientific proof that they can assist in weight loss. Most have been found to lead to serious side effects, such as heart damage.

The Federal Trade Commission is responsible for regulating consumer protection laws and making sure weight loss and supplement companies aren’t in violation of advertising guidelines. Gudzune and her colleagues set out to examine weight loss programs to see if there was a need to expand on consumer protection laws to prevent Americans, especially those who are obese, from paying for ineffective weight loss programs.

More than two-thirds of adults in the U.S. are obese or overweight, so health improvement programs are big business. However, lack of oversight for these programs could be especially concerning for those who need professional help to reduce the risk of metabolic diseases like heart disease and type 2 diabetes, the researchers note.

"Most programs can cost anywhere between $40 to $600 per month and are not often covered by insurance," Gudzune said. "And for many consumers, they could lose more weight from their wallets than their waists. We also need to look more closely at program cost and insurance coverage in future studies, as this information will be helpful for patients and referring doctors."

Source: Gudzunean K, Bloom B, Mehta AK, and Clark JM. Guideline-concordant weight-loss programs in an urban area are uncommon and difficult to identify through the internet. Obesity . 2016.