Professor Joseph Proietto

Professor Joseph Proietto – MBBS, PhD, FRACP

Professor Joseph Proietto is an Endocrinologist specialising in Diabetes and Obesity.  He is a world-renowned investigator of the management of obesity.  Professor Proietto established the first public obesity clinic in Victoria at the Royal Melbourne Hospital and is now Head of the Weight Control Clinic at Austin Health.  He is a senior specialist at the Austin Health Endocrinology Clinic.  He is a past President of the Australian and New Zealand Society Obesity Society (ANZOS).


  • Diabetes – Type 1 & Type 2
  • Obesity & Overweight
  • Metabolic Syndrome

Proietto Weight Loss Program

Obesity is the scourge of the 21st century.  Most people believe that the only cause of obesity is a poor lifestyle.  In fact, there is very good evidence that to become obese it is necessary to have a genetic predisposition. This has been demonstrated by identical twin studies and adoption studies and many genes causing obesity have already been discovered.

Obesity is of major concern because it causes many health problems including Type 2 diabetes, insulin resistance, metabolic syndrome, obstructive sleep apnoea, fatty liver, polycystic ovarian syndrome, arthritis, and cancer and more.

Fortunately weight loss improves most of these health issues and leads to improvements in the quality of life.

It follows that most obese individuals should lose weight. The problem is that the failure rate of weight loss programs is very high.

In 2011 we discovered the reason why most people regain weight after weight loss (Sumithran P. et al. Long term persistence of hormonal adaptations to weight loss. New Engl J Med 365:1597-604 2011). We showed that following weight loss the circulating blood hormones that regulate hunger (there are 10 of these) change their levels in a direction to make the individual more hungry and that these changes persist for at least one year.  This explains why most people struggle to maintain weight loss and justifies the use of appetite suppressants for weight maintenance.

In 2013 we discovered why ketogenic diet are more successful than other approaches to weight loss (Sumithran P. et al. Ketosis and appetite-mediating nutrients and hormones after weight loss. Eur J Clin Nutr 67:759-64 2013).

In 2014 we disproved the myth that “the quicker you lose weight, the quicker you will regain it”. (Purcell K et al. The effect of rate of weight loss on long term weight management: a randomised controlled trial. Lancet Diabetes Endocrinol 2: 954-962 2014). In this study we also found that rapid weight loss is easier and more successful than gradual weight loss and that the hormone changes described above are still there 3 years after weight loss.

With these three studies we have defined how obesity should treated.

In the Proietto Weight Loss Clinic a scientifically based weight loss program is used both to achieve a large weight loss and to maintain it long term.