Our weight loss surgery experts explain obesity and BMI, what causes obesity, risks of carrying excess weight and treatment options.
What is obesity?
Obesity is a medical condition characterised by excess accumulation of body fat. A body mass index (BMI) of 30 or more falls into the obese category.
Obesity and BMI
BMI is a measurement that uses your height and weight to determine which weight category you fall into: underweight, healthy weight, overweight or obese. There are different classes of obesity for a BMI of over 30, 35 and 40.
Your BMI also provides an estimate of how much body fat makes up your total body weight. Health professionals use BMI to assess how much of a risk your weight poses to your health. It can also help you and your healthcare team to decide which weight loss strategies may work best for you.
You can work out your BMI by dividing your weight in kilograms (kg) by your height in metres squared (m2).
For example, if you weigh 103kg and you are 1.75m tall, your BMI calculation would be 103 ÷ 1.752 = 33.63. So, your BMI is 33.63.
Health professionals also sometimes work out the health risks of excess body fat by measuring your waist circumference. A waist circumference of over 80 cm in women, and 94 cm in men, is linked with a higher risk of developing chronic health conditions.
What causes obesity?
Obesity is a complex condition, and many factors can contribute to its development.
Diet
If your diet is high in calorie-dense foods your body may get more energy than it needs, leading to weight gain. Foods that contain a lot of calories include those that are high in added fats and sugars, along with sugar-sweetened drinks and alcohol.
Physical activity levels
Movement and activity use energy. A sedentary lifestyle that includes long periods of sitting and minimal physical activity can contribute to weight gain.
Genetics
Genetic factors can make you more susceptible to gaining weight. Genes also play a direct role in obesity in some disorders, including some rare genetic forms of obesity.
Hormones
Several hormones are involved in controlling your appetite, metabolism and fat distribution. A lot of evidence links hormonal imbalances with obesity. Weight loss also triggers hormonal changes that encourage weight regain. This can lead to a vicious cycle that makes it very hard to both keep losing weight and to maintain weight loss.
Human biology
Our biology makes it much easier to gain weight than to lose it. We are programmed to eat when food is available, and our bodies are very good at storing energy.
Poor sleep
Studies have linked lack of sleep with obesity. This is partly because lack of sleep leads to hormonal changes associated with weight gain, such as increased levels of the hormone that makes you feel hungry (ghrelin).
Environmental and social factors
Our environment and circumstances can have a significant influence on our eating habits and activity levels. Environmental factors that can contribute to obesity include:
- easy availability of calorie-dense foods and oversized portions
- advertising that encourages consumption of unhealthy foods
- lack of time to exercise or prepare healthy, nutritious meals.
Psychological factors
Emotional factors like stress, depression, and emotional eating can lead to overeating and obesity.
Health conditions
Certain health conditions, such as hypothyroidism, Cushing’s syndrome and polycystic ovary syndrome (PCOS), can contribute to weight gain.
Medications
Some medicines can also cause weight gain, including corticosteroids and some medications used to treat seizures and mental health conditions.
The health risks and impacts of obesity
Obesity can have a significant impact on your physical and mental wellbeing. Being obese increases your risk of developing several health conditions including:
- heart disease and high blood pressure
- type 2 diabetes
- high cholesterol
- some cancers
- lung and breathing problems
- stroke
- kidney and gallbladder disease
- musculoskeletal problems, such as arthritis, gout, and joint pain
- sleep problems
- sexual health problems
- difficulties with pregnancy and labour.
The more excess weight you carry, the higher the risk of developing these conditions. Being obese can also make it harder for you to manage existing health conditions. It can also reduce your life expectancy.
Benefits of weight loss
The good news is that losing even 5 to 10% of your body weight can make a significant positive difference to your health. Weight loss benefits include:
- improvements in blood pressure and HDL (bad) cholesterol
- better control or remission of type 2 diabetes
- enhanced sexual function
- reduced symptoms of polycystic ovary syndrome and menstrual irregularities
- improved fertility
- greater mobility and physical function
- increased energy levels
- enhanced mental wellbeing and self-esteem
- reduced disease risk.
Treatment options for obesity
There are numerous obesity treatment options.
Lifestyle changes
For most people, dietary changes and increased physical activity are the first line of obesity treatment.
Medications
Some prescription medications can help you lose weight or prevent weight regain. The choice of medication will depend on personal factors and preferences. Your doctor can discuss these with you.
Gastrointestinal devices
This relatively new type of weight loss therapy involves inserting a device into the stomach via a thin, flexible tube (known as an endoscope). Endoscopic gastrointestinal procedures include:
- Gastric balloon – which involves passing a balloon into the stomach to take up space, so you can’t eat as much.
- Endoscopic sleeve gastrectomy – which involves stitching the stomach to reduce its capacity.
Bariatric surgery
Weight loss surgery can lead to substantial and lasting weight loss. Bariatric surgery involves altering the digestive system to help you lose weight effectively. It is a well-established and effective option for people with obesity who have not achieved significant weight loss through other methods.
Various bariatric procedures are available in Australia, including:
- Gastric sleeve surgery (sleeve gastrectomy) – in this procedure, a portion of the stomach is removed, leaving a smaller stomach.
- Gastric bypass surgery – these procedures involve rerouting the digestive tract to bypass a portion of the stomach and the upper part of the small intestine.
- Adjustable gastric banding (lap-band) – this procedure involves placing a band around the upper part of your stomach to make a smaller pouch. The band can be tightened up or loosened to control food intake.
- Bariatric revision surgery – people who have experienced complications or insufficient weight loss after an initial surgery may need a revision procedure.
For people who are eligible, weight loss surgery can be life changing. Benefits include significant and sustained weight loss, improvement or remission of health conditions and enhanced quality of life.
Don’t wait to start your weight loss journey
Obesity is a complex health issue, but it’s not insurmountable. If you would like to lose weight, start with a visit to your GP. They can explain more about how your weight affects your health and help you choose the right obesity treatment approach.
If you are considering weight loss surgery, consult a qualified specialist or doctor to assess your eligibility and discuss which procedure is right for you. Remember, you’re not alone. With the right treatment and a team of dedicated professionals to support you, weight loss is definitely achievable.
We’re a Centre of Excellence
Norwest Private Hospital was evaluated based on rigorous and proven standards set by SRC. Accreditation requirements encompass physicians’ surgical expertise and experience, the standardisation of clinical pathways, consultative services, equipment and instruments, and patient education.
This accomplishment demonstrates Norwest Private Hospital’s commitment to delivering the highest standard of care and excellence to our patients.
Find out more about bariatric & weight loss surgery at Norwest Private Hospital
*Whilst effort is made to ensure that the information contained on this website is accurate and informative and it has been reviewed by a qualified medical practitioner, the information is general in nature, and it should not be used as a substitute for obtaining your own professional or medical advice. Any timeframes or quantitative data including but not limited to estimated timeframes for recovery following a procedure, time required for the procedure, timeframes for weight loss and/or estimated total weight loss are general in nature and your experience, outcomes and results may vary.
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