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Comparison of micronutrient deficiency prevalence following Gastric Sleeve versus Roux-en-Y Gastric Bypass

Micronutrient deficiencies are common after bariatric surgery, irrespective of the kind of procedure. To assess the need for nutritional support for Gastric Sleeve, or Sleeve Gastrectomy (SG) patients, a comparison to Roux-enY Gastric Bypass (RYGB) patients on their nutritional deficiency prevalence, was made. All obtained postoperative vitamin and mineral supplementation. Levels of hemoglobin, iron, ferritin, zinc and vitamin B12 were determined preoperatively and at 3, 6, 12 and 24 months after surgery.

Iron deficiency prevalence after Gastric Sleeve and Gastric Bypass

Two years after surgery, the percentage of excess weight loss was statistically comparable between the two techniques, ranging from 81% (SG) to 88% (RYGB). Preoperatively, deficiencies were found for hemoglobin, iron, ferritin, zinc and vitamin B12. Over time, levels of hemoglobin and ferritin further decreased in both groups, resulting in a higher prevalence of hemoglobin and ferritin deficiencies. No statistically significant difference was found between SG and RYGB.

High deficiency rates for SG patients

This study illustrates that, despite common belief, nutritional deficiencies are highly prevalent after SG. Between groups, the prevalence of several nutritional deficiencies was comparable. Even though WLS Optimum 1.0 contained elevated doses of vitamins and minerals, the prevalence of micronutrient deficiencies remained high. WLS Optimum only significantly affected mean serum levels of folic acid, PTH and vitamin B1, and led to lower anemia rates compared to sMVS.

The need for tailored supplementation

Iron and zinc levels increased postoperatively after SG, but not after RYGB. After two years, zinc deficiencies were observed more regularly in RYGB patients (30%), compared to SG patients (6,6%). Iron and vitamin B12 deficiencies were found comparably prevalent for both patient groups. These results show that nutritional support is needed after bariatric surgery. However, since absorption and deficiency levels differ per procedure, supplementation should be tailored to the specific type of operation.

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Smelt et al. found higher mean serum concentrations of ferritin, folic acid, vitamin B1 and vitamin D and less deficiencies in vitamin B12, ferritin, folic acid and vitamin B1 in Gastric Sleeve patients using WLS Optimum 1.0, compared to patients using standard food supplements. However, anemia was diagnosed more often in WLS Optimum users.

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Efficacy of WLS Forte after a Roux-en-Y Gastric Bypass

A customized multivitamin supplement lowers postoperative deficiencies after a Roux-en-Y Gastric Bypass. Since iron, vitamin B12 and folic acid deficiencies often occur after a Roux-en-Y Gastric Bypass (RYGB), patients are advised to take daily food supplements. Based on literature and pilot studies, FitForMe developed WLS Forte in 2010, a bariatric multivitamin supplement customized to the…

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Ferraz, A.A.B., Carvalho, M.R.C., Siqueira, L.T. et al. (2016) Micronutrient deficiencies following bariatric surgery: a comparative analysis between sleeve gastrectomy and Roux-en-Y gastric bypass. Rev Col Bras Cir 45(6):e2016 

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