The most common procedures performed for weight loss today are the sleeve gastrectomy and the gastric bypass. But which is better? This is a good question and has led to much debate over the last ten years. In terms of weight loss, although early data seemed to favour the gastric bypass, most modern data suggests they are both equally effective; however there are still reasons why one might be ‘better’ than the other.

In a lot of cases surgeons will perform procedures based on patient preference, however, there may be some situations when the surgeon may advise one over the other.

Acid reflux

In general, patients who suffer with significant acid reflux symptoms are likely to do better after a gastric bypass. This is largely because the gastric bypass is an excellent procedure for improving reflux symptoms – and is a recognised procedure for acid reflux on its own. This is not the case after the sleeve gastrectomy which may sometimes lead to worsening acid reflux – particularly in people who already suffer with acid symptoms.

Absorption of medication after surgery

Absorption of medication may be a consideration when deciding on the type of procedure. Patients who are taking lots of medications may be advised not to have a bypass as the absorption of these medications may be affected after surgery. The sleeve tends not to interfere with absorption quite as much and may therefore be preferable for these patients.

The gastric bypass and diabetes

Any procedure that leads to weight loss will help control diabetes – and generally the more weight loss, the more significant the improvement; with many weight loss procedures leading to complete resolution of diabetes altogether.

Both the sleeve gastrectomy and gastric bypass can lead to substantial sustained weight loss and therefore both have a significant benefit on diabetic control and resolution. After a gastric bypass, however, there is a significant change in specific gut hormones that improve how the body processes both insulin and glucose. Because of these hormonal changes – which are seen to a lesser extent after a sleeve gastrectomy – the bypass, therefore, may be recommended by your surgeon if you are diabetic.

Sleeve gastrectomy as a ‘revisional’ weight loss procedure

The risk of regaining significant weight after the gastric bypass and sleeve gastrectomy is thankfully very low and most people only ever need one operation during their lifetime. However, weight regain can happen and further surgical intervention at this stage may be sort. After the gastric bypass there are fairly limited ‘re-operations’ available and some of the more drastic revisional procedures may risk significant malabsorption side effects.

However, it is possible to re-operate in patients who have had a sleeve gastrectomy to convert them to a form of gastric bypass.  This is generally a more technically straight forward and safe procedure and can lead to significant further improvement in long-term weight loss without malabsorption side effects.

Younger patients – who have many years to potentially regain weight – and patients who are ‘super-obese’ (BMI >50) – may also benefit from a sleeve gastrectomy with the potential to convert to another procedure if needed further down the line.