The truth about it is that most of these surgeries do not keep the weight off. There a many that suffer complications and some do die.
Actually, the above is NOT true.
There are a number of different operations that have been proposed for weight reduction. These include the jejunoileal bypass (now decidedly out of favor), vertically-banded gastroplasty, roux-en-y gastric bypass, and the more recent gastric banding procedure.
There is no cook-book one-size-fits-all procedure. As with any surgery, risks must be weighed against benefits.
Appropriately performed procedures must also be part of a comprehensive multidisciplinary chronic regimen, including periodic nutritional assessment. Long-term followups have shown that indeed a significant amount of excess weight is lost and stays off. The complication rates are relatively low, but are not zero.
If you are considering this surgery, find a surgeon certified by the American Board of Surgery; a center that has been certified for bariatric surgery; and ask your surgeon and other physicians about the procedures and followup.
A few links:
http://www.mayo/gastric-bypass/hq01465clinic.com/health
http://www.asbs.org/
http://jama.ama-assn.org/cgi/content/full/294/15/1986
I have the roux-en-y, but my husband has a biliopancreatic diversion (BPD) because his triglycerides were off the charts. We're both doing extremely well because of those surgeries.
I understand my situation may be unique but when I weighed 308lbs, my health overall was good but I had low blood sugar, low blood pressure and ran anemic. VERY odd with a huge family history of diabetes and heart disease.
With the roux-en-y my surgeon left me with the usual 7ft of small intestion when sometimes he goes as low as 5. I was used to running food through 40ft so the 7 was as drastic as he wanted to take it. Also with a roux-en-y no intestines are removed (at least he left them), just rerouted.
I'll never forget the conversation with him after I got out of surgery:
Me: "You left in all 40 feet? What the heck am I gonna do with 40ft of small bowel??"
Doctor Mac: "You never know! You might be in Detroit and get shot!"