Obesity is defined as an excess body fat in relation to lean body mass resulting from caloric intake that exceeds energy usage. It is normal for all of us to have a small amount of fat in our bodies as it is a most efficient way of storing energy. However in obesity, these fat stores become excessive.
One way you can measure if you are obese or not is by calculating your Body Mass Index (BMI). BMI is the measure of body fat based on height and weight that applies to both adult men and women. BMI is defined as your weight in kg divided by the square of your height in metres. BMI does not differentiate between body fat and muscle mass. Therefore, body builders and people who have a lot of muscle bulk will have a high BMI but are not overweight or obese.
If your BMI is equal to or greater than 30, you are obese.
BMI less than 19
BMI 19 to 24.9
BMI 25 to 29.9
BMI 30 to 39.9
BMI of 40 and above
Morbid obesity is defined by a level of obesity which is associated with diseases that result from the obesity and pose a serious health risk.
If your BMI is equal to or greater than 40, you are morbidly obese.
Very simply, caloric intake (through food and drink) is greater than energy usage (through physical activity). To maintain weight, the body needs a fixed amount of food energy per day. This amount can be estimated accurately for any given age, weight, gender and body make-up. If the body gets more than this amount, it increases its fat stores.
Obese people have more risk for:
Type II diabetes mellitus
High blood pressure
Obstructive sleep apnoea (OSA)
Gastro-oesophageal reflux disease (GORD)
Non-alcoholic steatohepatitis (NASH)
Stress urinary incontinence
Problems with fertility and pregnancy
Joint problems (e.g., arthritis)
Psychological problems such as depression
Certain types of cancer (breast, uterine, prostate, colon)
These can be divided into non-surgical treatments and that requiring an operation (surgical).
Diets: Unfortunately, these do not provide effective long-lasting weight loss. At best, they will achieve 10% weight loss which will disappear on stopping them.
Medicines: These too do not provide long-lasting sustained weight loss, averaging only 5-10% weight loss whilst the medicine is being taken. They have many side-effects including diarrhoea, headaches, high blood pressure, depression and may not be suitable for everyone.
Weight-loss or Bariatric surgery is currently the most efficacious treatment for morbid obesity and has arguably the best long term outcomes.
You will achieve on average between 50-70% excess weight-loss (depending on the operation you undergo) but more importantly the weight loss will be permanent and there will be marked improvements in your health. In particular, most if not all the health risks associated with obesity will be reversed or markedly improved. The consequence of this is that your life expectancy will return to what it is if you were not suffering from obesity.
The surgical treatment for obesity these days is minimally invasive using laparoscopic technique. This is less damaging to the patient as the incisions used are keyhole sized and this in turn results in faster recovery.
The following are the most commonly performed operations. Each of these has advantages and disadvantages, making each suited to a particular kind of patient.
Choosing between these options can be difficult. Also, not all surgeons offer all of the newer treatments for obesity.
Option 1. Laparoscopic adjustable gastric band / Lap band surgery
The operation involves placing an inflatable silicon band around the upper part of the stomach, creating a small pouch with a narrow passage, or ‘channel’ leading into the larger remainder of the stomach. The band connects to an access port by a thin tube and the port is placed under the skin. A fine needle is used to inject fluid through the skin into the port which fills the gastric band and adjusts its size. This has two effects: (1) the band causes restriction and thus limits the amount of food that can enter your stomach and (2) it reduces the appetite of patients. Over time the decreased food intake makes you loose weight. On average, patients tend to lose 50% of their excess body weight with the band.
Option 2. Laparoscopic Roux-en-Y gastric bypass / gastric bypass surgery
This operation involves bypassing some of the stomach and part of the small intestines. The stomach is divided to leave a smaller pouch and then a section of the small intestine is attached to the small stomach pouch that has been created. The procedure works in a number of different ways: (1) the smaller stomach pouch will make you feel full earlier; (2) it will also reduce your appetite; (3) by bypassing a portion of your intestine, you will absorb fewer calories that are taken by mouth. On average, patients tend to lose 60-70% of their excess body weight with this procedure.
Option 3. Laparoscopic gastric sleeve / sleeve gastrectomy
This is a relatively new approach. It involves reducing the size of the stomach leaving a long narrow stomach tube of approx. 100ml inside. The segment of stomach that is cut is removed out of your body. The procedure also works by making you feel full earlier after meals as well as reduce your appetite and thus allows you to consume fewer calories. On average, patients tend to lose 50-60% of their excess body weight with this operation.
Gastric band: Patients usually go home the same day or next day
Gastric bypass: Patients usually stay 2 nights in hospital
Sleeve gastrecomy: Patients usually stay 2 nights in hospital.
You will generally need to take 1-3 weeks off work depending upon the operation.
Gastric band: The complications include the band slipping or moving into the stomach, an increase in the size of the stomach or gullet (oesophagus), rupture of the ring or infection of the port. This may result in the band or port needing to be removed, repositioned or replaced. Overall, there is a 5-10% risk of adverse effects (as listed above) and a 1 in 2,000 (0.05%) risk of death caused by having this operation. Up to one in 10 patients will need further surgery for these or other complications.
Gastric bypass: The complications include leakage from one of the joins in the bowel, narrowing of one of the joins or ulceration of the gastric pouch. A second operation may be required to correct this. As with any operation, there are risks associated with having a general anaesthetic including a small risk of wound infection / hernia, chest infection, deep vein thrombosis (‘DVT’ or blood clots in the legs), and pulmonary emboli (blood clot in the lungs). Most people will not experience any serious complications from their surgery. Overall, there is a 2-5% risk of adverse effects and a 1 in 200 (0.5%) risk of death caused by having this operation.
Sleeve gastrectomy: The complications include leakage and bleeding from the staple line along the stomach. This can occur in 2-5% of patients and will require a second operation to treat. As with any operation, there are risks associated with having a general anaesthetic including a small risk of wound infection / hernia, chest infection, deep vein thrombosis (‘DVT’ or blood clots in the legs), and pulmonary emboli (blood clot in the lungs). Most people will not experience any serious complications from their surgery. Overall there is a 5% risk of adverse effects as listed above and 1 in 500 (0.2%) risk of death caused by having this operation.
In accordance with the National Institute for Clinical Excellence (NICE) criteria, bariatric surgery can be considered for patients who:
Are aged over 18 years of age
BMI equal or over 35 kg/m2 with any co-morbidity due to their weight and failed to lose weight after 6 months on a medically supervised lifestyle programme
BMI equal or over 40 kg/m2 and failed to lose weight after 6 months on a medically supervised lifestyle programme
BMI equal or over 50 kg/m2
Have no medical or psychological reasons which contraindicate surgery
Are fit enough to undergo an anaesthetic and surgery
Understand the need for long-term follow-up
Mr. Agrawal is frequently asked about the differences between the common laparoscopic bariatric/weight-loss operations, so in this section you will find a comparison to help you make decisions for your treatment. Please click here to see this comparision chart.