Ten years ago some 20,000 weight-loss operations were undertaken in America each year. In 2006 that figure is anticipated to reach an incredible 200,000.

Today about two thirds of the population of America is overweight, with about a third of these people being classed as clinically obese. Further, a staggering nine million adults are more than 100 pounds overweight and are classed as morbidly obese.

For these people the established remedy of diet combined with exercise simply doesn't work and they are turning in increasing numbers towards gastric bypass surgery.

The most frequently chosen form of gastric bypass surgery now is a procedure called Roux-en-Y in which a stomach pouch is created, using a section of the stomach itself, that is then connected to the small intestine, bypassing a large part of the stomach and duodenum. the procedure to hold substantial quantities of food but, having bypassed the duodenum, fat absorption is also greatly reduced.

The growing popularity of Roux-en-Y gastric bypass surgery, helped along by such things as its use by a host of high-profile celebrities, expanded coverage for the procedure by Medicare and some enterprising marketing, has led to an increase in the number of medical facilities providing the procedure. Some of these facilities are however better than others and a few are perhaps a little too concerned with the profit to be made from providing gastric bypass surgery. In turn, this presents an escalating danger for those considering surgery.

Results can be quite impressive, not only in terms of the weight loss produced but also in terms of the striking improvement that can be made to the patients overall quality of life. Despite this, gastric bypass surgery is major surgery and is certainly not suitable for everyone and is not without risks.

But just what are the risks involved?

Well, the risks of gastric bypass surgery will clearly vary from one person to another and anybody thinking about surgery should consult a doctor to discover the risks that surgery carries in their particular case. Here however, in only very general terms, are a few of risks usually associated with gastric bypass surgery:

Death. As with any major operation there is a risk of death associated with gastric bypass surgery and estimates place the short-term risk at around one or two percent. The risk varies with other medical conditions, general health and age.

Pneumonia. Being excessively overweight puts extra stress on both the chest cavity and the lungs. This creates an additional risk of contracting pneumonia following surgery.

Narrowing of the opening between the stomach and small intestine. Though seldom seen, this complication may require either an outpatient procedure where a tube is passed through your mouth to widen the narrowed opening or surgery to correct the problem.

A leak along one of the staple lines in the stomach. Leakage along the staple line in the stomach can result in and this is normally cured using antibiotics. Most cases heal in time but, from time to time, this leakage can be sufficiently serious to need emergency surgery.

Blood clots forming in the legs. The risk of blood clots forming in the legs is most commonly seen in the case of very overweight patients and, when blood clots do form, the situation can quickly become dangerous. Now and then blood clots travel to the lungs where they lodge themselves in the arteries of the lung creating a pulmonary embolism - a serious and life-threatening condition which damages the lung tissue.

Gastric bypass surgery can also induce dumping syndrome, a condition where the contents of the stomach move too rapidly through the small intestine causing diarrhoea, sweating, nausea, dizziness and vomiting.

Other commonly seen complications of gastric bypass surgery include hernia, intolerance to some foods, gallstones, bleeding stomach ulcers, vitamin and mineral deficiency and dehydration.

Advances in surgical techniques are rendering gastric bypass surgery safer by the day and the introduction of laparoscopic surgery and the use of robotics, currently being evaluated at Stanford University Medical Center in California, are also reducing post-surgical complications and enabling patients to recover more quickly.

Despite the risks for every problem case there are a thousand cases of thinner and happier people walking around. So, if you are considering gastric bypass surgery consult your doctor and, while you certainly need to consider the risks, don't automatically dismiss the procedure simply because of them.