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January 3, 2005

Penn Researchers Evaluate Major Commercial
Weight Loss Programs

(Philadelphia, PA) -- Obesity continues to plague an ever-growing number of Americans, dramatically increasing not only their girth, but also their chances of developing Type 2 Diabetes, heart disease and other debilitating illnesses. The situation is further complicated when those seeking to lose weight generally have only glossy advertisements or testimonials to guide them to an appropriate source of help. To address this problem, researchers at the University of Pennsylvania School of Medicine have evaluated major commercial diets and self-help weight loss programs, providing physicians and their overweight patients with the first comprehensive review of these resources. The article will appear in the January 3, 2005 issue of the Annals of Internal Medicine.

Adam Gilden Tsai, MD and Thomas A. Wadden, PhD, examined four types of programs: non medical, medically supervised, Internet-based, and organized self-help (e.g. Overeaters Anonymous). For each of the largest nationally based programs in these categories, the authors described the principal treatment components, staff qualifications, and costs (as determined from company websites and discussions with program representatives). The average weight loss for each program was determined by reviewing scientifically acceptable studies. The review examined only programs that required regular in-person or on-line contact.

“Our principal goal was to give health care providers sound information about the many weight loss programs available so they can advise their overweight patients,” said Dr. Tsai, Instructor of Medicine with the University’s Weight and Eating Disorders Program. “Physicians in busy primary care practices frequently do not have the time or training to provide needed weight loss counseling. We hope this review will serve to inform them of options in their community.”

Among non-medical commercial programs (including Weight Watchers, Jenny Craig, and LA Weight Loss), the authors found that Weight Watchers was the most thoroughly tested. Participants in two studies lost approximately 5% of their initial weight (about 10 pounds) in three to six months. Attending Weight Watchers group meetings weekly for three months was estimated to cost $167. The costs for Jenny Craig and LA Weight Loss were substantially higher, and no scientifically acceptable evaluations of weight loss have been published.

Medically supervised plans, including Health Management Resources (HMR) and OPTIFAST, produced average losses of 15% - 25% of initial weight (about 30-50 pounds) in three to six months. These plans, which include the use of a liquid diet to replace all or most foods eaten, were estimated to cost $1700 - $2200 for the first three months. (This covered all medical care, group lifestyle counseling, and the liquid diet). “This approach may be appropriate for persons who have significant obesity-related health complications such as Type 2 Diabetes or hypertension,” commented Dr. Wadden, Director of Penn’s Weight and Eating Disorders Program. Enthusiasm, however, for this approach is limited by findings that people regain approximately 50% of lost weight one to two years after treatment. “Weight regain is a problem following all weight loss efforts, but particularly after this regimen,” Wadden noted.

The review revealed minimal scientific evidence to support the use of a new generation of Internet-based weight loss plans. “But we know additional studies are being conducted and, if found effective, the Internet could provide weight management to millions of Americans,” Tsai explained. Similarly there has been little evaluation of self-help programs, including Overeaters Anonymous and Take Off Pounds Sensibly (TOPS), that charge minimal or no fees. “Despite the lack of documented effectiveness, organized self-help approaches are an important option for persons who cannot afford commercial programs,” said Wadden.

The authors stated that all of the programs reviewed had undoubtedly been of help to some individuals. They hope their review will encourage health care providers and their patients to start talking about excess weight, even if commercial or self-help programs are not an option.

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PENN Medicine is a $2.7 billion enterprise dedicated to the related missions of medical education, biomedical research, and high-quality patient care. PENN Medicine consists of the University of Pennsylvania School of Medicine (founded in 1765 as the nation’s first medical school) and the University of Pennsylvania Health System (created in 1993 as the nation’s first integrated academic health system).

Penn’s School of Medicine is ranked #3 in the nation for receipt of NIH research funds; and ranked #4 in the nation in U.S. News & World Report’s most recent ranking of top research-oriented medical schools. Supporting 1,400 fulltime faculty and 700 students, the School of Medicine is recognized worldwide for its superior education and training of the next generation of physician-scientists and leaders of academic medicine.

Penn Health System is comprised of: its flagship hospital, the Hospital of the University of Pennsylvania, consistently rated one of the nation’s “Honor Roll” hospitals by U.S. News & World Report; Pennsylvania Hospital, the nation's first hospital; Presbyterian Medical Center; a faculty practice plan; a primary-care provider network; two multispecialty satellite facilities; and home health care and hospice.

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