This procedure is more successful than restrictive procedures, such as gastric banding, because it does not rely solely on behavior modification. While the pouch helps create a feeling of fullness and does not allow for large meals to be consumed, the calories that are consumed are not fully used by the body due to the bypass of part of the small intestine.
Because weight loss is not totally dependent upon the continuation of eating very small meals alone, patients typically lose at least 60% of their excess weight after surgery; over a third lose 80%. Most patients reach their lowest weight about two years after surgery. One recent study showed that 90% of patients maintain a loss of half their original body weight ten years after having surgery, a result that has only been shown with Roux-en-Y and a similar surgery, biliopancreatic diversion. Unfortunately, the biliopancreatic diversion–and sometimes the roux-en-y–causes difficulties with obtaining adequate nutrition and absorbing enough vitamins and minerals.
Potential Drawbacks of Gastric Bypass Surgery
Of course, there are negatives to this — and any — procedure. Many patients experience dumping syndrome, a condition where food moves very quickly from the stomach into the small intestine, causing feelings of nausea, cold sweats, chills and often severe diarrhea and chest pain. Most patients find that limiting meal size and sugar consumption prevents dumping syndrome.
Malnutrition is also a risk, as this procedure decreases the body’s ability to absorb nutrients, and most patients need vitamin and mineral supplementation for the rest of their lives.
The surgery is not reversible, but the restrictive nature of the surgery can be eliminated by consistent overeating, which can stretch the pouch until the amount of food able to be digested and used by the body is far less restricted than intended by the surgeon. If you desire this change, speak with your doctor so you can devise a plan to help you do this comfortably and safely.
Overall, gastric bypass is the most commonly performed weight loss surgery. While it is a complex surgery with significant risks, patients have historically had better results with total weight loss, long-term weight maintenance and improved overall health than those who have opted for any other type of weight loss surgery.
What can go wrong?
As with any surgery, there is a risk of infection or that the surgery doesn’t work. There might also be bleeding or leaks from the staple line or joins, or bowel obstruction.
Some people find they have low blood sugar after gastric bypass surgery and feel weak. A few don’t absorb all the nutrients they need. Talk to your doctor about the risks of the procedure.
Also, be sure to ask your doctor any questions you might have about gastric bypass surgery.