After bariatric surgery, the risk of developing low or deficient levels of important vitamins and minerals increases.
This is partly due to changes in food intake and partly due to the body’s decreased ability to absorb nutrients. With the gastric bypass, this decreased absorption is mainly due to the bypassing of the stomach and the first part of the intestine. With both the bypass and sleeve, the small pouches produce less of both hydrochloric acid (HCl) and a protein called Intrinsic Factor which is needed to absorb certain vitamins and minerals, including vitamins D and B12, iron, calcium, and zinc.
Therefore, it is important to take vitamin and mineral supplements daily after surgery and have your blood tests taken at least once a year to make sure your levels are in the proper range. Of course, supplements don’t replace a healthy diet, so make sure you follow your clinic’s dietary advice in order to get the nutrients you need after surgery.