Citracal calcium creamy bites

Calcium is a nutrient of concern after all forms of WLS, primarily due to inadequate intake.  With RNY and DS there may also be concern of bioavailability of some forms like calcium carbonate.  Calcium carbonate combines with hydrochloric acid in the stomach to form calcium chloride which is ultimately well absorbed.  After RNY in particular, this is unlikely to occur.  A small comparative study between the two forms was conducted in post-operative RNY patients and also concluded that calcium citrate was significantly more bioavailable in this population[i].  For this reason, calcium citrate is the preferred form after WLS.  In DS and RNY, calcium deficiency is also secondary to vitamin D malabsorption.  Inadequate dietary intake of calcium may occur both due to decreased food volumes and avoidance of dairy products.  Calcium is commonly recommended as a post-operative supplement in the range of 1000--1500 milligrams per day.  Higher doses up to 2000 milligrams are sometime advised after DS.  All forms of surgery have been shown to produce increased bone turnover and loss of bone mass[ii], some of which is inevitable with massive weight loss.  Mark ers that can be followed include serum parathormone (PTH), 25-hydroxy vitamin D, ionic calcium, serum or urinary telopeptide, and bone density.  Complex cases may require co-management with an endocrinologist.

32 Chang CG, Simms T, Adams-Huet B, Sakhaee K, Jones DB, Provost DA. A Compaison of the Absorption of Calcium Citrate and Calcium Carbonate after Roux-en-Y Gastric Bypass. Clinical Proceedings of the 21^st Annual Meeting of the American Society of Bariatric Surgeons.  http://www.asbs.org/html/pdf/asbs_abstract_booklet.pdf (accessed January 19, 2005)

33 Coates PS, Fernstrom JD, Fernstrom MH, Schauer PR, Greenspan SL. Gastric bypass surgery for morbid obesity leads to an increase in bone turnover and a decrease in bone mass. J Clin Endocrinol Metab. 2004 Mar;89(3):1061-5. Found here:  http://app.barisecure.com/resources/NIWLS_NMD.doc