As many of us take on New Year’s resolutions to shed pounds, a new study shows which types of treatment work best. The study offers long-term data to support the use of intensive lifestyle intervention (ILI) as a viable weight loss tool.

According to more than eight years of data from the Look AHEAD study, published in the journal Obesity, ILI yields better results than a less rigorous diabetes support and education (DSE) program by encouraging patients to eat right and exercise through frequent group and individual counseling sessions.

Researchers found that people who used ILI attained an average weight loss of 8.6 percent during their first year, and 4.7 percent by the fourth year, compared to those in the DSE group, who lost just 0.7 percent in the first year and one percent by the fourth year.

By the eighth year of the study, 50 percent of patients using ILI had lost an average of more than five percent of their initial weight, while only 37 percent of DSE participants saw the same results.

Moreover, almost 40 percent of patients using ILI who lost more than 10 percent of their initial weight during the first year maintained that weight loss for a full eight years, showing that long-term weight control is possible with ILI.

Thomas Wadden, Ph.D., a professor of psychology at the University of Pennsylvania and author of the new study, said those who participated in the study ate a well-balanced diet of 1,200 to 1,800 calories per day and increased their physical activity level as part of the ILI.

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Wadden said that while some people may be able to lose weight and build healthy habits on their own, others benefit from lifestyle counseling by a registered dietitian or other health professional. With long-term data showing that ILI works, weight loss programs in 2014 and beyond will likely center on this type of counseling and group interaction.

Obesity Is a Disease—Now What?

In 2013, the American Medical Association (AMA) classified obesity as a disease. While some experts believe that the designation paves the way for better treatment and insurance coverage, others disagree.

Wadden believes that the AMA's decision will help increase insurance coverage for weight loss interventions like bariatric surgery.

“That would facilitate more overweight and obese Americans losing weight to improve their health and quality of life,” he said. 

But Robert Lustig, M.D., a clinical professor at the University of California, San Francisco, points out that the Department of Health and Human Services (HHS) classified obesity as a disease in 2004, and people still packed on pounds.

“It didn't make a difference in our expanding waistlines then, and it won't now,” Lustig said.

Lustig said that while there has lately been an increase in media attention and federal funding for obesity studies, this does not necessarily equate to any change in practice. He said that the only thing that will change is that physicians will be required to document in their charts that they've told their patients to diet and exercise, or they won't get paid for the visit, he said.

“That's not going to reduce anyone's waistline,” he added.

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Technology Will Power Future Obesity Treatments

Knowing that long-term weight loss is possible could inspire more overweight Americans to seek help through ILI and other methods.

Wadden believes that technology, including smartphones and social media, “holds promise” for increasing access to effective weight loss programs. Although making weight loss interventions available to all overweight and obese Americans is a challenge, he said that technology may help to overcome that obstacle.