Since the diet allows only small amounts of a limited variety of foods, it may be difficult to get enough vitamins and minerals from food alone. Deficiencies can develop in a matter of months. Iron, folate, vitamin B-12, and calcium are the nutrients most affected. Special Considerations Gastric bypass surgery creates dramatic changes in the size and shape of the stomach. It may take awhile to get used to these changes.
Patients report a wide variety of complications after surgery.
Some of these will go away with time, while others can be lessened with adjustment of the diet. Nausea and vomiting are the most common complications occurring in the first few months after gastric bypass surgery. They may occur after eating too fast, drinking liquids while eating, not chewing enough, or eating more than the pouch can comfortably hold. It is necessary to learn to eat very slowly and chew foods thoroughly. Nausea and vomiting can also be triggered after trying new foods.