Weight-loss surgery can promote better health through long-term weight loss. With sustained weight loss, diseases including type 2 diabetes, high blood pressure, sleep apnea, high cholesterol and osteoarthritis are either greatly improved or completely gone. With disease improvement, medications to treat these problems are reduced or discontinued. Plus, with a big decrease in food intake after the surgery, diabetics often have a huge improvement in blood sugar, even before a large amount of weight is lost.

There are many psychological benefits, too, including improvements in self-esteem, personal confidence and quality of life. With weight loss, most people can return to many of the physical activities they used to enjoy before excess weight prevented their mobility. These range from walking and biking to simply playing in the yard with their children.

The surgery has direct benefits, too. First, people can sustain a long-term eating pattern of caloric restriction (usually around 1,000 to 1,500 calories a day), with increased contentment and no deprivation. When hunger signals kick in, a moderate amount of food can now satisfy. Second, the likelihood of keeping most of the weight off is very high, so while 100-plus pounds of weight loss can be accomplished without surgery, the operation helps tremendously with preventing weight regain.

The major benefit of the most popular surgeries is their ability to decrease food intake while allowing the patient to feel full and relatively satisfied. The surgery gives the patient a tool to help her navigate in a world of high-volume and high-calorie eating.

Most of the medical benefits stem from weight loss. Everything from high blood pressure to sleep apnea (shallow breathing and frequent prolonged periods between breaths) are improved by significant weight loss:

• As many as 8 out of 10 patients with sleep apnea can improve to the point that they no longer need devices to help them get enough oxygen into their lungs and bloodstream during the night.
  
  
• Arthritis often improves, too. Weight-bearing joints, such as the knees, hips and ankles, often become less painful with the decrease in stress and pressure that the weight causes.
  
  
• Trouble with controlling urination, as well as excess swelling of the legs and ankles, are usually improved in proportion to the amount of weight lost.
  
  
• For people with type 2 diabetes, the surgeries also help regulate blood sugar. The antidiabetic effects come both from weight loss, which improves the effectiveness of the insulin made by the patient's body, and from a very positive effect caused by a change in the way food is absorbed, since, with a portion of the small intestines and stomach bypassed, fewer calories pass through. There is also a change in certain hormones the body produces. These effects are only beginning to be fully understood, but can lead to rapid and exciting improvement in blood sugar control.

Weight-loss surgery has many benefits. It is the most effective intervention available for leading to substantial and sustained weight losses. Medically, weight-loss surgery has resulted in dramatic improvements in type 2 diabetes, glucose intolerance, hypertension, dyslipidemia, obstructive sleep apnea, gastro-oesophageal reflux disease (GERD), asthma, ovarian dysfunction, infertility, urinary incontinence and other conditions associated with obesity. For example, in obese persons with type 2 diabetes, there is often an immediate improvement in blood sugar control.

Psychological functioning often improves dramatically, too. Depression is common in severely obese persons, and weight loss following surgery frequently is associated with significant reductions in depression.

Quality of life often improves as well. So does self-evaluation of appearance. I believe that these improvements in psychological functioning are oftentimes as important, if not more so, than the improvements in medical risk factors.

There are many significant and lasting benefits of weight-loss surgery. All of the procedures result in significant and sustainable weight loss.

The amount of excess weight you can expect to lose:

• Gastric banding: 40 to 50 percent
• Gastric bypass: 65 percent
• Biliopancreatic diversions: 65 to 75 percent

Most patients keep it off, too. Long-term studies have shown that 75 to 80 percent of patients will maintain their weight loss.

More significant than the weight loss itself is the improvement in medical conditions associated with severe obesity. These include type 2 diabetes, high blood pressure, sleep apnea, severe heartburn, shortness of breath with exertion, many cancers, infertility in women, painful joints and a condition called pseudotumor cerebri, an increase in pressure inside the brain, typically occurring in younger women, that can cause severe headaches, seizures and blindness.

Recently, several excellent studies have been published that describe the improvements in these conditions—notably diabetes, cardiovascular disease; and improvements in life expectancy. In addition, it has been well recognized that patients who do well after surgery have an improved quality of life.