Even though the number of overweight and obese Americans has increased over the past two decades, the weight counseling offered by primary care physicians has decreased to fewer than one in 15 office visits, according to a new Penn State study.

Researchers analyzed outpatient records from the National Ambulatory Medical Care Survey for the years 1995-1996 and 2007-2008. Over that period, the results showed had 46 percent lower odds of receiving weight counseling — occurring in only 6.2 percent of visits in that year — despite the fact that the percentage of adults who were overweight or obese increased from 52.1 percent in 1995 to 63.3 percent in 2008.

The findings, published in the journal Medical Care, also indicated fewer than one in three obese patients were given recommendations on weight-loss strategies. In addition, those with high blood pressure were 46 percent less likely to receive counseling, and diabetes patients were 59 percent less likely.

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"It is striking that the odds of weight loss counseling declined by 41 percent, with only 29.9 percent of obese patients receiving counseling in 2007-2008, given the substantial increases in the rates of overweight and obesity during that time," said Jennifer Kraschnewski, M.D., assistant professor of medicine at the Penn State College of Medicine. "People with these conditions stand the most to gain from the weight counseling."

According to the U.S. Centers for Disease Control and Prevention, more than 145 million adult Americans are overweight or obese.

In 2003, the U.S. Preventive Services Task Force — created to make evidence-based recommendations about preventive services including screenings and counseling — recommended that physicians screen all patients for obesity and offer counseling to promote weight loss.

"Unfortunately, other studies have shown that physicians do not conduct weight and weight-related counseling for the majority of their affected patients," Dr. Kraschnewski noted.

She said the reasons for the drop are unclear. But researchers suggested doctors may not feel they have adequate training to make such recommendations, that patients may not change change, and time limitations during appointments don’t allow for detailed conversation about exercise, nutrition, diet, and other lifestyle approaches aimed at shedding pounds.

Another reason: Counseling services are not reimbursed.

Dr. Kraschnewski said the findings point up the need to make weight counseling in the primary care setting a bigger priority.

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"Primary care has long been instrumental in significant public health successes such as decreased stroke and heart disease deaths due to the management of high blood pressure and high cholesterol," she said. "However, unlike these conditions, primary care providers lack effective tools to address the obesity epidemic.

"PCPs serve on the frontlines of health care and must be actively engaged to help address the nation's obesity epidemic."