Why is treating obesity so difficult? Justification for the role of bariatric surgery

Joseph Proietto
Med J Aust 2011; 195 (3): 144-146.


  • There is little evidence that public health measures adopted so far have had any impact on the rise in the prevalence of obesity.

  • Weight-loss programs have a very high long-term failure rate.

  • There is emerging evidence that weight is regulated by the hypothalamus and is physiologically defended.

  • There is also a strong genetic predisposition to the development of obesity.

  • The availability and promotion of high-energy foods and the absence of any obligatory need for physical activity compound the problem, but this social change is not easily reversible.

  • One way forward is to focus public health measures on preventing obesity in children while making resources available to treat people who are already obese, including providing funding for bariatric surgery in public hospitals.

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  • Joseph Proietto

  • University of Melbourne, Melbourne, VIC.



Many thanks to Priya Sumithran and Scott Baker who read and offered helpful advice on the manuscript. I am supported by the Sir Edward Dunlop Medical Research Foundation.

Competing interests:

I was chair of the Optifast medical advisory committee for Nestle until 2010. I was a member of the expert panel that developed guidelines for bariatric surgery for the treatment of type 2 diabetes.

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