Gastric Bypass Surgery

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Heart And Gastric Bypass Information (SCROLL DOWN FOR GASTRIC BYPASS)

Gastric Bypass Surgery: Nutritional Deficiencies to Watch-Out For

Gastric bypass surgery is any procedure that divides the stomach into two parts, the upper pouch being smaller and the lower being larger. Aside from the division of the stomach, the surgery also involves arranging the small intestines to allow the pouches to get connected. There are several ways to attach the intestine; hence the different names of gastric bypass procedures (GBP).

The primary indication for someone to undergo operation is to treat morbid obesity, having a body mass index (BMI) greater than 40. It is likewise required to treat type 2 diabetes mellitus, hypertension, sleep apnea and other coexisting medical conditions. In general, all treatments for obesity are termed bariatric surgery, including gastric bypasses.

The dramatic results concomitant with gastric bypass surgery greatly reduced the chances of other co-morbid conditions. Any GBP significantly reduces the stomach volume, leading to altered reaction to food. This event leads to a noticeable weight loss, and medically speaking, a person with a normal, controlled weight is generally at lesser risk to illnesses. However, although GBP puts an end to obesity, this surgery may also lead to nutritional malabsorption and deficiencies.

Nutritional Insufficiencies with GBP

The organs involved with gastric bypass procedures may pose a nutritional risk to a person who will undergo operation. There is always a great danger of poor digestion and absorption of food and nutrients following GBP. That’s is why, it is very important for one to know about these deficiencies so that appropriate nutritional modifications can be initiated. The following are some of these nutrient deficiencies:


After a gastric bypass surgery, there is an increased probability to developing hyperparathyroidism because of poor absorption of calcium. Predominantly, calcium is absorbed in the duodenum. However, the surgery bypasses the duodenum, thus the calcium ion is gone to waste. Reabsorption of calcium can be achieved by taking Vitamin D and calcium citrate supplements.

Iron Deficiency

Even without surgery, iron is constantly depleted in the human body, especially in menstruating women. Since it this mineral is absorbed in the duodenum, an intestinal part that is taken when a gastric bypass surgery is performed, the loss of this part leads to the reduction of iron intake. This condition must be countered with supplementation. Iron is responsible for the red blood cells to carry oxygen to the different parts of the body. Ferrous sulfate can be taken, however some persons claim considerable gastrointestinal distress when taking this drug. Other substitutes to ferrous sulfate include ferrous fumarate, or other iron chelations.


The mineral zinc provides many biological functions to the human body, including immune resistance, wound healing, digestion, physical growth, reproduction, and many more. It is also responsible in some biochemical processes in the body like metabolism and protein synthesis. Since zinc absorption is also affected by a gastric bypass surgery, supplementation is important. A number of zinc supplements are readily available in the market, which can be easily absorbed, such as zinc acetate, zinc citrate, zinc picolinate, zinc glycerinate, and zinc monomethionine.

Vitamins B1 and B12

Vitamin B1, also known as thiamine, is responsible for the neurologic functions of the body and when deficient may cause permanent neurologic damage. On the other hand, cobalamin or vitamin B12 is absorbed in the gastric mucosa with the aid from intrinsic factors and when depleted may result to pernicious anemia and other neuropathies. These water-soluble vitamins are at great risk of being junked because of the small gastric pouch after surgery. Supplementation with medication is the best treatment for the deficiency of these nutrients, with special indication to cobalamin, which can be given as sublingual B12 or injection.


Protein deficiency is the most definite danger with gastric bypass surgery. Because of the anatomical structure of the bowel after surgery, patients can suffer regular vomiting (until the GI system adapts to the changes), and may eat fewer amounts of meals. Protein supplements are generally required to prevent excessive muscle wasting and hair loss after the surgery.

Vitamin A

Some GBPs impair the absorption of fats, causing a deficiency of vitamin A, a fat-soluble vitamin. This vitamin is responsible for proper vision, skin health, and bone growth. Retinol and beta-carotene supplements are available to fight off vitamin A deficiencies after surgery.

It is important to note that after a gastric bypass surgery, there is a marked uncertainty to the total nourishment of the body especially because the operation involves the gastrointestinal system. In this instability, supplementation is the only cure. Luckily, there are a variety of options to choose from to combat undernutrition. Gastric bypass surgery may post malnourishment risks, but with proper diet and supplements, these risks can definitely be prevented.