Long-term benefits of weight loss?

The editorial “Family Physicians and Obese Patients”¹ raises many good questions but the most important one apparently remains unasked and therefore unanswered: When we encourage patients to lose weight, whether through lifestyle modifications or medication, what are the long-term effects on important outcomes such as all-cause and cardiovascular mortality, complications of diabetes, and overall patient well-being? We should be asking not just how best to help patients lose weight, but also “Should we be encouraging them to lose weight at all?”

A task force report² reviewed currently available evidence, which is limited to mostly short-term (average of 12 months) studies examining changes in surrogate markers for disease (body mass index, blood pressure, blood glucose level, lipid levels).³ Most interesting is the authors’ observation that most patients will lose an average of only 3 kg and almost all will gain the weight back. What are the potential long-term psychological, metabolic,⁴ financial, or other harms associated with this repeated weight cycling?

Given the lack of convincing evidence for long-term benefit and the uncertain risks, I was surprised at the conclusion that weight loss interventions are “effective.”

I appreciate the difficulty in developing recommendations in the absence of adequate evidence. But there is reasonably good evidence that a healthy (eg, Mediterranean) diet and improved cardiorespiratory fitness⁵ are more important than “fatness” in overall mortality risk. Until we have better evidence to show that weight loss actually makes people healthier in the long term, it might be preferable to focus on proven diet and fitness goals while avoiding the emphasis on weight loss, which carries with it an implicit weight-shaming message and is likely to result in repeated “failure.”

• Copyright© the College of Family Physicians of Canada