Micronutrient Deficiencies in Morbidly Obese Women Prior to Bariatric Surgery

Although morbid obesity is related to excess of energy and macronutrient intake, it does not rule out the presence of micronutrient deficiencies. The aim of this study was to evaluate food intake and the prevalence of micronutrient deficiencies in a group of morbidly obese women seeking bariatric surgery.

A total of 103 morbidly obese women were studied prior to bariatric surgery. Anthropometry and body composition (dual-energy X-ray absorptiometry, DEXA) were performed on all subjects. Energy and nutrient intake was determined by food frequency questionnaire. Blood tests to assess micronutrients status, including plasma iron, ferritin, transferrin, zinc, copper, calcium, phosphorus, hemoglobin, hematocrit, mean corpuscular volume (MCV), and hair zinc, were performed. Folic acid, vitamin B12, vitamin D, and parathyroid hormone (PTH) were also assessed in 66 subjects.

Mean energy intake was 2801 ± 970 kcal/day. Carbohydrate, protein, and lipid intake represented 55 ± 9.1, 13.9 ± 3.3, and 32.5 ± 8.2% of total energy intake, respectively. Iron, calcium, and vitamin D intake was below the recommended dietary allowance. The prevalence of nutritional deficiencies were as follows: plasma iron 12.6%, ferritin 8.7%, transferrin 14.6%, plasma zinc 2.9%, calcium 3.3%, phosphorus 2.3%, hemoglobin 7.7%, hematocrit 13.6%, MCV 6.8%, and hair zinc 15.7%. In the subsample, 10.6% had a vitamin B12 deficiency, 71.7% showed low concentrations of vitamin D, and 66% had high PTH levels. No folic acid or copper deficiencies were detected.

Despite high daily energy intake and adequate macronutrient distribution, morbidly obese Chilean women seeking bariatric surgery present with deficient intake of some micronutrients and a high prevalence of micronutrient deficiencies.