Advantages and Disadvantages of the Gastric Bypass

Advantages

It is particularly effective for patients with a larger BMI as the procedure has more predictable weight loss outcomes.
Hormonal changes resulting from surgery mean most patients have an almost immediate reduction in their need for diabetic medication and some are able to completely stop diabetic medication altogether.
Gastric bypass tends to have the strongest effect on high blood pressure, high cholesterol, and other obesity related health issues.
It does not require any on-going adjustments which are required with other procedures, such as the gastric band. Regular follow up is however necessary to ensure weight loss is appropriate and intake is nutritionally adequate.
It is effective for those people who tend towards high sugar or high fat foods. Dumping syndrome is directly linked to a high sugar, high fat intake. Symptoms of dumping are unpleasant and therefore discourage the intake of high calorie, sweet foods.

Although it is technically possible to reverse this operation, this is much more involved than with gastric banding (for example) and reversal is only undertaken in very rare situations.
Complications, although rare, are generally more serious than with other weight loss procedures, such as the gastric band.
There is a higher risk of nutritional deficiency due to the reduced absorption of vitamins and nutrients. Life-long vitamin and mineral supplementation is essential to prevent deficiency following surgery. Long term follow up with the surgeon and dietitian to monitor nutritional status is also very important.