8 Guidelines for diet, eating habits after weight loss surgery - 2
7. B-complex vitamins, iron and calcium require special attention
If you have had a gastric bypass or intestinal bypass, the following information is important for you to know. (This does not affect those who have had gastric banding operations.)
Vitamin B-12 is particularly difficult for your body to absorb after surgery, and you should look into taking it in forms other than a pill. Insufficient intake of vitamin B-12 will cause you to become fatigued easily.
Likewise, you should take calcium (as the citrate) in large amounts, to avoid early osteoporosis, a disorder in which the bones become porous, brittle and easily fractured.
Be careful with alcohol. It is absorbed and metabolized much more rapidly after surgery. In addition to the risk of rapid and unexpected intoxication, alcohol consumption can cause ulcers in your stomach pouch or intestine.