Registered dietician, Sunette Swart explains:

We know there are multiple causes with behavioural, hormonal, and neurological elements.  Obesity can lead to almost 200 different health problems, including diabetes and hypertension.  It is a treatable condition, and it has been shown that a 5% weight loss or more reduces the risk of complications and improves health.

Obesity treatment options include lifestyle changes (healthy eating, increased physical activity, stress management, mental health, and good sleep quality), medication, and bariatric surgery.  Behavioural changes can result in a 5–15% weight, whereas bariatric surgery can result in a weight loss of 35%–40% up to two years after surgery.

“Bariatric surgery” derives from the Greek word “baros,” which means “weight.” The first weight-loss surgery was performed in 1953, and bariatric surgery has since evolved into what is now known as metabolic surgery.

To qualify for Bariatric surgery, you must be between the ages of 18 and 65 years, with a body mass index (BMI) of 40kg/m2 or more or with a BMI of  35 kg/m2 or more with at least two co-morbid conditions (like diabetes, high blood pressure or high cholesterol).

Surgery can be performed as laparoscopic (keyhole) or open.  There are three types of bariatric surgery procedures:

  1. Restrictive – sleeve gastrectomy and gastric banding
  2. Malabsorptive – biliopancreatic diversion with duodenal switch (BPD-DS) and single anastomosis dueodeno-ileal with gastric sleeve (SADI-S
  3. Combined restrictive and malabsorptive  – the Roux-en-Y gastrectomy


The sleeve is involves removing approximately 80% of the stomach, leaving a banana-shaped stomach with a volume of 50ml – 150ml. This results in smaller portions and less food consumed overall. Food continues to pass through the small intestine in the same manner as before surgery, as shown in Figure 1. The hungry hormone, ghrelin, is reduced by removing a portion of the stomach.

Figure 1: Sleeve gastrectomy


The Roux-en-Y gastric bypass is regarded as the gold standard in weight loss surgery due to its effectiveness and durability.  The name is a French expression that means “in the shape of a Y.”  The stomach is divided into a small egg-sized pouch and the larger part is left unused. The small intestine is divided into two sections. The new stomach pouch is linked to the bottom end of the small intestine, allowing food to pass through. The top portion of the small bowel (where stomach acids and digestive enzymes pass from the “old” stomach) is connected to the small intestine during the final stage of the procedure, forming the Y shape seen in Figure 2. As a result, the Roux-en-Y gastric bypass combines restrictive and malabsorption procedures. The patient eats less, feels fuller faster, and as the food bypasses contact with the first part of the gastrointestinal tract, there is less absorption. Gastric acid reflux is treated as well.

Figure 2: Roux-en-Y gastric bypass


The SADI-S procedure is a newer variation of the duodenal switch that is easier to perform, takes less time in the operating room, and requires only one surgical bowel connection. The stomach is reduced in size by removing approximately 85% of it (same as the sleeve gastrectomy). The small intestine is then bypassed approximately 50% (longer than in the Roux-Y-Gastric Bypass).  This results in nutrient malabsorption due to the shorter path that digested food takes through the intestines, but with the benefit of added digestive enzymes, as illustrated in Figure 3. Bowel movements after this procedure are likely to be looser and more frequent bowel movements.  Lifelong vitamin supplementation will also be necessary.


Figure 3: Single anastomosis dueodeno-ileal with Sleeve gastrectomy (SADI-S)


Biliopancreatic diversion with duodenal switch (BPD-DS)

This procedure combines a sleeve gastrectomy with a much longer Y-shaped intestinal bypass than the RYGBP. The food bypasses about 75% of the small intestine, resulting in a decrease in energy and nutrients.  As shown in Figure 4, the bile and pancreatic digestive juices only mix with the food at the very end of the small intestine. The hormone changes this procedure causes is more superior and this causes a significant reduction in hunger, increased feeling of fullness and excellent blood sugar control.  This is a highly complex surgery that can cause dumping (symptoms such as nausea, vomiting, abdominal cramping, diarrhoea, bloating, sweating, dizziness, and a fast heart rate), malnutrition, and loose stools. Protein intake, as well as life-long vitamins, are critical due to malabsorption (especially vitamins A and D).

Figure 4: Biliopancreatic diversion with duodenal switch (BPD-DS)

Bariatric surgery in South Africa

Bariatric centres must be staffed by a multi-disciplinary team consisting of the surgeon, physician, registered dietician, biokineticist and psychologist. The patient begins the journey with a consultation with one of the Specialist Physician. Our practice is affiliated to the Bespoke Surgical Institute at Zuid-Afrikaanse Hospital, Pretoria.  Patients will can be seen for pre and post surgery care in the Sunward Park Medical Centre with the actual surgery done by the Pretoria team.  Contact Wendy at our centre for further information.



Monday – Thursday 8:00 – 17:00
Friday 8:00 – 16:00
Weekends Closed

(011) 896 2420

3 Albrecht Rd, Sunward Park, Boksburg, 1459


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