Vitamin and mineral deficiencies are not unusual following gastric bypass surgery. Most vitamins and minerals are absorbed through the small intestine. Because part of the small intestine is bypassed during gastric bypass surgery, the newly shortened small intestine absorbs fewer vitamins and minerals. This surgical change can be the cause of nutritional deficiencies.
Food intake is reduced following weight-loss surgery. Prior to bariatric surgery, the average stomach holds about three-pints of food. After bariatric surgery, that amount is reduced to about one ounce. Because of this reduction, gastric bypass patients meet only 50 percent of their daily need for vitamin D through food sources.
Vitamin D is needed to maintain appropriate blood levels of calcium and phosphorus. Vitamin D assists in the absorption of calcium and helps to form and maintain bones. It also increases bone mineral density while decreasing fractures.
Vitamin D Deficiency
A deficiency of vitamin D can cause rickets, a disease characterized by soft bones and deformities. Inadequate levels of vitamin D are associated with cardiovascular disease and cancer. Research also suggests that vitamin D can help prevent hypertension and type 1 and type 2 diabetes.
Sources of Vitamin D
Foods that are sources of vitamin D include salmon, mackerel, tuna fish, eggs, liver, beef, and cheese. Sunlight is also a important source of vitamin D.
Of the supplements, vitamin D3 is the most useful. It is the only vitamin that the body can produce from sunlight. It is most bio-available to gastric bypass patients in a liquid form.
Calcium is the most plentiful mineral in the body and is important for bone health, blood clotting, muscle and heart functions, and nerve transmission. Food sources of calcium include dairy products, tofu, orange juice, and leafy vegetables.
Calcium is absorbed into the bloodstream from the small intestine. Absorption of calcium depends on Vitamin D levels, and these two nutrients are often taken simultaneously. Ninety-nine percent of calcium is in bones and teeth.
Malabsorption is when nutrients are not absorbed as well as they were prior to gastric bypass surgery because of the reduced size of the small intestine. Low calcium levels can result in muscle spasms, restricted growth, irregular heart rate, and hypertension.
When calcium levels are deficient in the bloodstream, calcium is drawn from the bones to compensate. Osteoporosis can occur if bone is being regularly broken down but not rebuilt.
The two types of calcium are calcium carbonate and calcium citrate. Calcium citrate is the type of calcium that is suggested for weight-loss surgery patients because they have lesser amounts of stomach acids after surgery and calcium citrate will be absorbed more easily.
Recommended dosages of calcium to supplement the calcium from the standard gastric bypass patient diet are 1500 to 2000 mg. per day.