Obesity is defined as a body mass index ≥30 kg/m2. In the United Sates it is estimated that 35 percent of adults (roughly 100 million people) are obese. Body Mass Index Calculator.
Diseases Linked to Obesity
There are a number of diseases that are linked to obesity such as diabetes, heart disease, stroke, cancers (such as breast, colon, uterine), arthritis and obstructive sleep apnea.
Risk of Surgery
There will always be a risk with surgery. Attempts at weight loss need to be documented. Usually a nutrition assessment and supervised weight loss are required before considerate can be given to a weight loss procedure.
Weight loss surgery candidates will need medical clearance as well as a behavior assessment. This is to ensure that behavioral problems which can affect weight loss have been addressed such as depression and substance abuse.
Support groups are also advised as they will help motivate you throughout the process.
The patient needs to have realistic expectations. If you are not dedicated to losing weight then your results will not be as good.
The gastrointestinal tract anatomy
After food is swallowed it makes its way down the esophagus into the stomach. The food will then go into the duodenum which is the beginning of the small intestines. Juices from the pancreas and gall bladder will mix with the food. The food will travel down the small intestine as nutrients are absorbed along the way. The left over and then go into the large intestine also known as the colon. From the colon the waste then goes out the anus.
Types of surgery can be broken into two types
Restrictive procedures will reduce the size of the stomach allowing you to fill full with less food. This procedure reduces the amount of calories consumed.
Gastric banding is a type of restrictive procedure. This type of procedure is reversible, the band can be removed.
A sleeve gastrectomy is another type of restrictive procedure. This makes the stomach smaller. Unlike the gastric band, this procedure is not reversible.
There is concern with time the smaller stomach will enlarge again when restrictive procedures are used.
Malabsorption procedures will result in less fat absorption. This can be done by shortening the small intestine that absorbs nutrients and fat. Bilio-pancreatic diversion is another type of malabsorption procedure. The gall bladder and pancreas produce substances that help absorb the food in the small intestines. If this tract is divided, these substances cannot reach the small intestine and less absorption will occur.
Some procedures will be both restrictive and malabsorptive.
Roux-en-Y is a type of procedure where the stomach is smaller. Some of the the small intestine is bypassed so that less fat absorption occurs.
This procedure can lead to long-term vitamin/mineral deficiencies including vitamin B12, iron, calcium, and folate.
Biliopancreatic Diversion with Duodenal Switch (BPD/DS) Gastric Bypass has the best success with weight loss but there is a higher complication rate with these procedures. This procedure also has a greater potential to cause both protein and vitamin deficiencies. Some surgeons will opt for this type of surgery if previous surgeries have been unsuccessful.
In addition to making the stomach smaller and bypassing the intestines there are additional factors that help with weight loss. The hormone ghrelin is produced mostly by the stomach with small amounts produced by the pancreas and small intestine. If the stomach is made smaller, it is expected that there will be less ghrelin produced. Ghrelin is known as the hunger hormone, it stimulates the appetite and promotes fat storage.
Malabsorption can lead to vitamin deficiency
An article in the published March 31 in JAMA Ophthalmology discussed a woman who had severe vitamin A deficiency which can lead to lesions on the eye (sclera). These lesions resulted in dryness that changed the woman’s vision.
What has been done to shorten recovery of weight loss procedures?
Most procedures are performed with a laparoscope. The recovery is shorter than with an open procedures. Currently, the most common procedure is the Roux-en-Y, the second most common procedure is the gastric sleeve. Gastric band procedures are being performed less often then they had been.
The American College of Surgeons Find a Surgeon