Bariatric Surgery & Vitamin D Deficiency

Bariatric surgery, also called weight loss surgery, can improve a patient's overall health status by helping him lose weight and reduce his risk of developing obesity-related conditions such as diabetes, heart disease, osteoarthritis and certain types of cancer. However, patients must make long-term changes to their lifestyles and diets to maintain weight loss. They must also guard against nutrition deficiencies by taking daily supplements for the rest of their lives.

Vitamin D

Vitamin D, a fat-soluble vitamin, helps with calcium absorption into the bones, immunity and growth and development. Vitamin D deficiency can cause osteomalacia, softness and weakness in the bones. A severe or long-term deficiency in vitamin D may cause permanent disability due to loss of bone, as well as disorders of the immune and nervous systems. Symptoms may include muscle twitching and spasms, fractures, seizures, falls, depression, high blood pressure and irregular heartbeats.

Bariatric Surgery Procedures

Bariatric surgery procedures help morbidly obese patients -- those who are more than 100 lbs. overweight -- lose significant amounts of weight. Restrictive procedures such as adjustable gastric banding, or AGB, reduce food intake by restricting the stomach to an egg-sized pouch. Malabsorptive procedures such as the biliopancreatic bypass diversion, or BPD, reroute the digestive system to block some calorie absorption. Gastric bypass procedures combine both mechanisms by reducing the size of the stomach and rerouting part of the digestive system.

Vitamin D Deficiency and Bariatric Surgery

Even before surgery, as many as 25 to 80 percent of morbidly obese patients have vitamin D deficiency, according to an article published in the October 2009 issue of "Pediatric Clinics of North America." Postoperatively, vitamin D deficiency is more common after gastric bypass and BPD procedures that reroute the digestive system than after the less-invasive adjustable gastric banding surgery, according to a study published in the September 2008 issue of "Surgery for Obesity and Related Diseases." All bariatric patients, however, need vitamin D and calcium supplementation to prevent bone loss after surgery.

Treatment

Patients with vitamin D deficiency before surgery should take 50,000 IU of ergocalciferol once a week for 8 weeks, according to "Surgery for Obesity and Related Diseases 4." After surgery, taking 1,200 mg of calcium and the 400 to 800 IU of vitamin D in multivitamin compounds may be adequate for 50 percent of gastric bypass patients, but the others may need more to prevent bone loss. BPD patients may need as much as 2,000 IU of vitamin D daily. Other measures that assist with bone health after bariatric surgeries include weight-bearing exercise, increasing dietary intake of calcium-rich foods and moderate exposure to the sun. Patients should also stop smoking and reduce alcohol and caffeine intake.