Know the facts about bariatric surgery

Who is a typical bariatric surgery patient

How does bariatric surgery work

Weight loss surgery…

is a treatment which minimises the amount of food you can eat by reducing the size of your stomach. There are a range of weight loss treatments available which have been designed to help you lose weight, reduce your portion sizes and lead a healthier lifestyle.

Each weight loss surgery has their own advantages and disadvantages, with some being less invasive than others. At New Leaf our expert bariatric surgeons will work with you to identify the most effective treatment, helping you to get the most out of your weight loss goals.

Common weight loss procedures include gastric plication, RNY gastric bypass, Mini gastric bypass and sleeve gastrectomy. Below you will find explanations of the different types of surgery to help you to decide.


EWL – (excess weight loss)

(excess weight loss) this is the average weight loss statistic. For example if you need to lose 10 stone to get to a bmi of 25 an ewl of 50% would mean that on average a patient would lose 5 stone


Gastric Sleeve



This procedure is now the number one Bariatric procedure in the world. Other names for this operation are vertical sleeve gastrectomy (VSG) or gastric sleeve resection of the stomach. It originated as part of another surgical procedure, called a biliopancreatic diversion with duodenal switch, where the sleeve resection was performed first as part of this procedure. Gradually it became clear that, for a number of clients, this first procedure was in itself sufficient, and so this procedure has been launched independently. This procedure was finally adopted in 2008 and has been recognized as a fully-fledged operation.

✓ Criteria BMI 35 or above or 30 with Diabetes Type 2 or other co-morbidities
✓ Approximately 80% of the stomach is removed, so you can’t eat as much as you could before.
✓ You feel satisfied with much smaller portions.
✓ The other important effect is that the levels of an appetite stimulating hormone (ghrelin) are reduced. Less ghrelin means lesshunger which in turn means you eat less.
✓ Some patients find the “not feeling hungry” overwhelming and eat very little post surgery.
✓ You can develop nutrient deficiencies, so you are advised to undertake a high protein diet and vitamin and mineral supplementation.
✓ This is a completely non reversible procedure.

Gastric Bypass RNY



✓ Criteria:BMI 35 or above.
✓ This surgery is regarded as the Gold Standard.
✓ The top part of the stomach is sectioned off to make a small stomach pouch the size of a large egg so you can’t eat as much as you used to.
✓ The small intestine is rearranged to connect to both (see image above).
✓ The surgery works by restriction and changes in gut hormones.
✓ Most patients with Type 2 Diabetes can expect to see remarkable improvement in blood sugar control, often without the need for any regular diabetic medications.
✓ If you eat sweet food you may develop dumping syndrome, where your blood sugars fall rapidly, and you feel hot, light headed, heart may palpate or feel faint.
✓ You can develop nutrient deficiencies so a high protein diet and vitamin and mineral supplementation is essential.
✓ This is both a restrictive and a malabsorptive procedure which produces the greatest metabolic effects but also has the potential of having more long term complications in the form of nutritional deficiencies.

The malabsorption component of this operation can increase the efficiency of the op when compared with purely restrictive operations (although recent studies show that there is a similar effect with the sleeve gastrectomy), but brings side effects in the form of deficiency of certain micronutrients such as iron, vitamin B12, vitamin D and others. In the postoperative period is therefore necessary to constantly monitor these nutrients and substitute with vitamin tablets (get your GP to give you regular blood tests).



✓ Criteria: BMI 35 or above.
✓ Similar to the gastric bypass however the small bowel is directly joined to the small stomach pouch (see images above) hence only one join.
✓ Only a single incision is required compared to 2 incisions with the gastric bypass.
✓ The procedure takes a little less time than the RNY gastric bypass.
✓ Instead of a small pouch like with the gastric bypass, the mini gastric bypass surgery procedure creates a narrow tube-like pouch that holds approximately 1-2 ounces, restricting the amount of food that can be taken in at one time.
✓ As some of the small bowel is bypassed you also have changes in gut hormones and feel less hunger.

✓ One of the disadvantages of this surgery compared to the gastric bypass includes a greater likelihood of experiencing bile reflux.
if you have reflux the gastric bypass is a much better option.
✓ As with the gastric bypass you can develop nutrient deficiencies so a high protein diet and vitamin and mineral supplementation is essential.

✓ You may develop dumping syndrome similar to the gastric bypass.
✓ Expected excess weight loss approximately 85%.
✓ Many patients experience changes in taste and food preferences

✓ Because you will eat less and absorb fewer calories, you will lose weight. Following surgery, and for the remainder of your life, it is important to take a bariatric multivitamin, calcium, vitamin B12, and iron (for women of menstruating age).


Sasi Bypass



A Promising new operation for obese and diabetic patients. SASI (single anastomosis sleeve ileal bypass) is a mixture between gastric sleeve and gastric bypass surgeries.

Firstly the surgeon makes a gastric sleeve  and then the surgeon bypasses part of the intestine and connects the pylorus of the stomach to the intestine.  This means there are two directions for the food to go.
Approximately 30% of food passes through the stomach in the normal way  so vitamins and minerals are normally absorbed.
Approximately 70% of food is bypassed  and so a lot of food and sugars are not absorbed which results in weight loss and treatment of diabetes.
✓ Criteria 35 or above
✓ Because the sleeve is present there is the added benefit of removal of fundus valve and therefore reduction in grehlin hormone responsible for high degree of satiety in patients.
✓ There is reduced possibility of reflux than with sleeve although for patients with reflux problems the gold standard still remains to be the RNY bypass
✓ Due to the fact that approximately 30% of food passes through the stomach without being bypassed there is much less chance of malnutrition and anaemia problems which can be associated with bypass alone.
✓ You may develop dumping syndrome similar to RNY bypass
✓ Is the most effective surgery to cure Diabetes type 2 as the percentage of improvement reaches 95%.
✓ Can help cure the patient from the disturbing obesity complications as hypertension, hypercholesterolemia and bone diseases.
✓ Because the passage to the duodenum is still intact it is much easier to detect duodenal cancer


Read about our criteria and contraindications, and check your BMI


Possible complications

Read about the possible complications with Bariatric surgery