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Definition of Obesity

Obesity is a chronic disease requiring multidisciplinary and long-term management.

For selected patients, obesity surgery (or bariatric surgery or weight loss surgery), combined with changes in eating habits and increased physical activity, is an effective weight loss method.

Surgery is the only current treatment that achieves long-term weight control in over 85 per cent of morbidly obese patients.

It can also be used to control or improve certain co-morbidities, to improve quality of life and reduce obesity-related mortality.


Obesity is defined by a BMI ≥ 30 kg/m2.

Calculation of BMI, target weight and excess weight allows patient treatment goals to be established. Location of excess fat is also a risk factor in obesity, therefore it is important to record waist diameter.

Classification BMI (kg/m2)

Success following an operation is generally defined as loss of over 50 per cent of excess weight or maintaining a BMI < 35.


Making the decision to operate →

After bariatic surgery, we see people eat to live; they no longer live to eat.