Is metabolically healthy obesity a worthwhile initial medical goal?

Worldwide, nearly one in three individuals is obese. As a consequence, increasing numbers of people suffer from diseases associated with morbid overweight, including diabetes, high blood pressure, heart attack or stroke. Despite the well-known health risks, only some of these individuals attempt to lose weight. Many people are most probably daunted by the prospect of losing the amount of weight required. Researchers of the German Center for Diabetes Research in Tübingen and Potsdam now report in the journal The Lancet Diabetes & Endocrinology that metabolically healthy obesity could be a worthwhile initial goal in the therapy of obesity.

Doctors repeatedly tell overweight and obese patients, "Being overweight causes serious health problems. You should lose weight." Through lifestyle interventions, the affected individuals often lose weight in the short term, but they usually regain weight over the long term. Furthermore, the question is whether the 5 to 8 percent weight loss rate recommended by medical associations is sufficient for every overweight or obese person to significantly reduce the risk of long-term health consequences. For instance, at an initial weight of 120 kg and a height of 180 cm (BMI, body mass index 37.0), the BMI of a patient would thus be 34.4 after the successful weight loss. But the patient would not have achieved the desirable BMI of 25 or less, the level at which most people are clearly protected against obesity-related illnesses.

Wouldn't it be more meaningful to define achievable intermediate goals to reach an individual healthy weight? What parameters could describe this intermediate goal? Can smaller steps more effectively motivate those affected to lose weight? These were the key questions in a study conducted by scientists at the Helmholtz Zentrum München and the German Institute of Human Nutrition (DIfE) in Potsdam.

In the study, professors Norbert Stefan and Hans-Ulrich Häring from Tübingen and Professor Matthias Schulze from Potsdam integrated the concept of metabolically healthy obesity into the risk management of obesity therapy. Based on their own data from the Tübingen Lifestyle Intervention Study, they show that weight loss of more than 10 percent with an average baseline BMI of 35 is likely to improve subjects from metabolically unhealthy obesity (MUHO) to metabolically healthy obesity (MHO). However, they also stress that that this percentage is insufficient in the long term, since the disease risk for MHO individuals is still increased by 25 percent compared to metabolically healthy people with normal weight. By contrast, for MUHO subjects who weigh just a bit more than MHO subjects, the risk of severe health consequences is 150 percent higher compared to the same metabolically healthy people with normal weight.

As an important intermediate step, Stefan describes the achievement of MHO as a documented protection against obesity-related metabolic diseases. "Look at this protection as low-hanging fruit. It is easier to achieve than to concentrate on the top fruits from the outset. Doctor-patient communication is an important support to motivate the patient to reach and at least maintain this condition."