Obesity: It Will Not Be Enough To Simply Treat The ConsequencesTuesday, April 5, 2016
Last week’s global obesity report published in The Lancet is accompanied by a thoughtful editorial comment by George Davy Smith from the School of Social and Community Medicine, Bristol, UK, who takes a rather realistic view of our attempts to reverse the epidemic.
As Smith points out,
“Prevention of the global increase in obesity is proving hard — partly for physiological reasons. With respect to calorie intake, weight change is a buffered and self-limiting process. Increased voluntary physical activity leads to compensatory decreases in other components of energy expenditure, resulting in little net benefit. In this respect, human beings are no different to other primates, and genetically informed studies suggest that the association between BMI and physical activity is generated to a large extent by higher BMI leading to lower voluntary physical activity, rather than vice versa.
Many proposals exist for comprehensive sets of advisory and legislative policies aimed at tackling obesity. Such presentations greatly outnumber interventions that have robust evidential support. Evaluations that use methods that allow for reasonable causal inference have been applied to several of these approaches with generally disappointing results, yet they have had little influence on the flow or content of the many “calls to action” on global obesity.”
Indeed, only time will tell if and when population approaches to obesity prevention will bear fruit.
As for our ability to reduce the health consequences of excess weight, Smith notes that,
“Many health consequences of high BMI are unlikely to be directly related to the increased weight itself, rather they are mediated by the adverse metabolic and physiological consequences of increased BMI, including higher blood pressure, adverse lipid profiles, and other metabolic consequences.
These links can be broken, particularly pharmacologically, which is now being done on a mass scale globally (although unevenly). These interventions will attenuate the anticipated morbidity and mortality sequelae of high BMI. However, some of the health effects—and many of the adverse economic consequences—of obesity will not be alleviated in this way.”
There are of course numerous complications of excess body weight, including sleep apnea, osteoarthritis, or urinary incontinence, for which we have no good medical treatments – all of these issues will likely be best mitigated by treating obesity itself.