Bariatric surgery, also known as weight-loss surgery, is an effective treatment for individuals who are considered severely obese (typically a minimum of 100 pounds above their ideal body weight). There are several types of bariatric surgeries, including gastric bypass, gastric sleeve and adjustable gastric band. All bariatric surgeries make changes to your digestive system which result in significant weight loss.
How Does Normal Digestion Work?
The digestive system is composed of a long, twisting tube that is designed to absorb nutrients and calories. This system consists of the mouth (where digestion starts), the esophagus, stomach, small intestinal and large intestine. Along the way a complex set of muscles move food through the digestive tract while you eat. Cells within the various parts of the digestive system make enzymes and hormones that break down the food you eat and allow the body to absorb protein sugar and fat.
What Does Bariatric Surgery Do?
Bariatric surgery changes the way you digest food. Although there are a number of different types of bariatric operations, they are all designed to reduce the size of your stomach which results in limiting the amount of food you can eat. Some surgeries do this by creating a small gastric pouch that is separated from the remaining stomach (i.e. gastric bypass) while others restrict the amount of food by actually removing a large part of the stomach (i.e. gastric sleeve). Another method is to place a band around the top of the stomach (i.e. gastric band). This procedure makes it possible to feel full while eating less food.
In addition to restricting the size of the stomach as described above, some bariatric surgeries also use the process of malabsorption (i.e. gastric bypass). In the case of gastric bypass, malabsorption occurs because a section of the small intestine is connected to the newly formed gastric pouch. By doing so, food “bypasses” about 30% of the small intestine which reduces the amounts of nutrients that are absorbed from the food you eat. This can further reduce the number of calories your body uses. It also affects the nutrients and vitamins absorbed from food. Most people who have bariatric surgery take vitamin supplements to avoid complications this can cause.