Nutritional Status, Body Composition, and Bone Health in Women After Bariatric Surgery at a University Hospital in Rio de Janeiro.

Introduction: Calcium and/or vitamin D deficiency can occur after Roux-en-Y gastric bypass (RYGBP) because of impaired absorption, resulting in secondary hyperparathyroidism and increased risk of reduced bone mineral density (BMD).

Objective: The objective of this study is to assess nutritional status, body composition, and bone health in women after RYGBP.

Method: Twenty-five premenopausal women who had undergone RYGBP (test group) and 33 women matched for age and body mass index who had not undergone surgery (control group) participated. Test group received 250 mg of calcium for day. Anthropometric, dietary, laboratory, body composition, and BMD (X-ray absorptiometry) analyses were performed.

Results: No differences were found between the groups in waist circumference, fat or lean mass, BMD, or dietary calcium intake, although calcium intake was low in both groups. The test group had better results for complete blood count, total cholesterol, low-density lipoprotein, and triglycerides. The mean parathyroid hormone was higher (p = 0.005) in the test group, although still within normal limits. Plasma levels of 25-hydroxyvitamin D were low in groups but did not differ between them (p = 0.075). Vitamin D concentrations were lower in women with longer time since surgery. The test group had lower intake of energy, protein, lipids, polyunsaturated fatty acids, fiber, phosphorus, and iron than the control group.

Conclusion: Elevation of parathyroid hormone, low dietary calcium intake, and vitamin D plasma insufficiency without BMD reduction occurred after RYGBP. Patients who underwent RYGBP had adequate lipid profiles but inadequate intake protein, polyunsaturated fatty acids, fiber, and iron. Vitamin D deficiency may occur in the late postoperative period.