One of the features that sets gastric bypass surgery apart from other forms of bariatric surgery is that it changes the route food takes through your digestive system. Food will be diverted from the upper part of your stomach into the lower part of your small intestine. It will bypass part of your stomach and small intestine, which can affect the way you digest and absorb food.

The Small Intestine

The small intestine is the upper part of your gut. Food goes into the small intestine after it leaves your stomach. At this point it will have been partially digested by the acids and enzymes of your stomach. Digestive juices and bile from the pancreas and liver will be added into the mix at the start of the small intestine. These help to further break down fats and proteins. As the food moves along your small intestine, the tiny fats, amino acids, sugars and other nutrients will be able to pass through the wall of the gut and into your blood stream. Slightly different nutrients are absorbed in different parts of the small intestine, which is divided into three sections: the duodenum, jejunum, and ileum. The nutrients that are absorbed will be carried in the blood to where they are needed or to places where they can be stored in your body for future use. The rest of your meal will go on into the large intestine, where more water can be absorbed, before the waste passes out of your body.

The Effects of Gastric Bypass Surgery

After you have had gastric bypass surgery, food won’t pass through your whole small intestine. This means that it will come into contact with less of the intestine wall through which absorption happens. It will also move through your gut more quickly. Your body won’t be able to absorb as much nutrition from your food, which should help you to lose weight.