Morbid obesity is a chronic health condition which contributes to high mortality and morbidity rates in western countries.

At Upper GI West, we recognise obesity is a disease process. It is different to the lifestyle issue of being overweight. It requires more than fine dietary adjustments alone to resolve. In fact if you have a BMI of 35 you only have a 5% chance of loosing significant weight and keeping it off without surgical intervention. If your BMI has been 40 then this chance lowers to 0.5%.

Mr Alan Thomas
Bariatric Surgeon Perth

What causes obesity?

There are many different causes for obesity. These include genetic, hormonal, metabolic, psychological and environmental factors. How each person digests, absorbs, stores and uses food and energy differs.


Obesity causes many health problems. These include diabetes, high blood pressure, heart disease, stroke, sleep apnoea, arthritis, depression and even cancer.

Why is obesity a disease and not just a lifestyle issue?

Obesity has occurred because of modern food processing methods. Insecticides, pesticides, preservatives, colourings and emulsifiers have damaged the gut lining of genetically susceptible individuals. This coupled with a modern diet rich in fructose syrup and other refined carbohydrates has caused a change in gut bacteria away from a protein based set of bacteria to a carbohydrate based set of bacteria. These bacterial changes in turn affect how calories are utilised in the body.

This combination of gut lining damage and calorie utilisation changes have caused the modern disease of obesity.

“Metabolism and physical activity both play an important role in obesity. When your energy intake exceeds your body’s requirements, the excess is stored as fat. Excess fat is harmful to healthy tissues and leads to many health problems.”
Mr Sanjeeva Kariyawasam
Bariatric Surgeon Perth

Obesity is on the rise due to changes in how we live. More and more people have sedentary jobs, perform less physical activity and eat larger amounts of foods.

However, the likeliest and most significant factors contributing to the modern epidemic of obesity are the gut damage and gut bacterial changes brought about by food additives. Especially emulsifiers and highly refined sugar products such as high fructose corn syrup that are so prevalent in the majority of processed and fast foods.

Why have weight loss surgery?

Losing weight is a health priority. Morbid obesity is the second most common preventable cause of death after smoking.

“Obesity causes many health problems. These include diabetes, high blood pressure, heart disease, stroke, sleep apnoea, arthritis, depression and even cancer. Unfortunately diets, exercise and medication don’t tend to help morbidly obese patients keep significant weight down long term. In fact once an individual has attained a BMI of 40 the chances of loosing significant weight and keeping it down without surgical intervention is only 1in200; even a BMI of 35 individual has only a 1in20 chance of long term weight loss without surgical intervention! ”.

Mr Alan Thomas
Bariatric Surgeon Perth

How effective is weight loss surgery?

Weight loss surgery for obese patients is unquestionably and scientifically proven to be the most effective way to ensure sustained weight loss in obese individuals.

“However, surgery alone isn’t enough. It’s still important to have a healthy diet and lifestyle. A suitable candidate for obesity or metabolic surgery would require a BMI of 35 or higher. A BMI over 30 with medical conditions readily improved by weight loss are also generally considered for surgery. However, a lower BMI may be considered for different ethnic groups or those with severe metabolic derangements. Other forms of obesity treatments may also be suitable for these individuals”.

Associate Professor Mo Ballal
Bariatric Surgeon Perth

Key Points

Overweight or obese patients are at greater risk of serious health problems
Weight loss surgery combined with lifestyle changes are by far the most effective ways to sustain weight loss in obese individuals

Types of obesity surgeries


Traditionally bariatric operations are classified as restrictive of malabsorptive, ie they are deemed to act by causing volume restriction to food intake or to cause malabsorption of foods that are ingested.

Recent research suggests that these procedures do not work in this manner. Rather they work by increasing the transit of food through the stomach and intestine which then cause various hormones and hormone receptors to change.

Coupled with this is a change in how the body burns up calories consumed. It is in the context of these changes that additional calorie reduction causes weight loss. 

Remember though that surgery itsself does not cause the weight loss; it gives you the means to lose the weight and maintain the weight loss but humans can trump any efffect of surgery if they put their mind to it. For example, they can consume lots of liquid calories, or they eat high density foods or nibble all day or even have lots of small meals. None of these should be occurring after surgery!

The only way surgery can absolutely cause weight loss is if you have a serious complication from the surgery. But this is most certainly not healthy and can be devastating for the patient, their families and the surgeon.

These are some of the reasons why we at Upper GI West invested an extra 3 years training in complex surgeries of the oesophagus and stomach. We are confident we can offer appropriate, carefully planned and performed operations for all our Bariatric patients. We are able to offer and perform all bariatric options including endoscopic bariatric procedures to appropiate patients.

The Upper GI West Approach

Upper GI West is a Perth surgery practice founded by Mr Krishna Epari and Mr Alan Thomas in 2008. Our practice brings together five of Perth’s most experienced Upper Gastrointestinal and Bariatric Surgeons to deliver the most advanced surgical care.
At our Perth clinic, we will look at your personal needs and look at you as a person, rather than just as a patient. It means that we will help you get clear about your options. We will help you prepare for surgery. And we will support you to make the necessary lifestyle changes.
To make sure you get the best care, we work together as a team. Your bariatric surgeon works with your dietitian so your care plan is personalised. We believe that it is essential to talk about your needs and your lifestyle, now and after your surgery. From experience, we know that is the key to making your journey as successful and comfortable as possible.