Plenty of people who are obese and medically need to lose weight say they get sick and tired of being told to eat less and exercise more. And for good reason: A growing body of research finds lifestyle and behavioral modifications often are not enough to help someone drop a significant amount of weight and keep it off.

A new paper published in the journal Lancet Diabetes & Endocrinology argues that it's high time for obesity to be recognized as a serious chronic disease with biological causes -- not just a result of poor eating habits and sedentary behavior.

The authors, a group of obesity treatment experts, say that while patients may be successful in the first few months of a weight loss program, some 80 to 95 percent will eventually put the weight back on. They say this is because obesity has a lot to do with underlying biological issues in the body that dieting simply can't change.

Get Breaking News Delivered to Your Inbox

"Although lifestyle modifications may result in lasting weight loss in individuals who are overweight, in those with chronic obesity, body weight seems to become biologically 'stamped in' and defended," Dr. Christopher Ochner, lead author and Assistant Professor of Pediatrics and Psychiatry at the Icahn School of Medicine at Mount Sinai in New York, said in a press statement.

Research is finding that restrictive diets jump-start the natural impulse to eat caloric foods. This biological response is perhaps a vestige of hunter-gatherer times, when humans didn't know where and when they'd find their next meal. Our bodies have maintained the ability to store away energy in the body as fat. And in this modern world, where meals and snacks are available around the clock and a dozen fast-food restaurants are a short distance from home, obesity has become a bigger problem.

The authors of the paper say we need to change the way we think and talk about obesity, and use language reflective of the fact that being morbidly obese is a chronic disease. Like addictions to drugs and alcohol, patients can overcome it but shouldn't expect to be "cured."

"Few individuals ever truly recover from obesity; rather they suffer from 'obesity in remission,'" Ochner says. "They are biologically very different from individuals of the same age, sex, and bodyweight who never had obesity."

In recent years, treatment for obesity has expanded beyond calorie-counting to include medical interventions such as bariatric surgery, prescription medications and even a medical device that blocks the vagal nerve, which is the main communication pathway between the stomach and other organs, and is involved in a number of digestive processes in the body. But it's possible that doctors are not utilizing these options as frequently as they should.

A growing number of studies have shown that weight loss surgery may be the most effective and longest-lasting treatment for obesity. Research has also found the surgery can reverse diabetes, a chronic disease that goes hand-in-hand with obesity. The STAMPEDE (Surgical Therapy And Medications Potentially Eradicate Diabetes Efficiently) study, published in the New England Journal of Medicine, is the largest randomized trial to date examining the effectiveness of treatments available for obese and diabetic patients. Overall, it found more than 90 percent of patients who received bariatric surgery were able to lose 25 percent of their body weight.

The experts behind this latest study say an increased focus on the biological factors underlying obesity will lead to more effective treatment. They warn the alternative -- continuing to rely on behavior modification, or diet and exercise alone -- "will surely result in the continued inability to treat obesity effectively and the premature death of millions of individuals each year."