title: Red meat intolerance in patients submitted to gastric bypass: a 4-year follow-up study.
abstract: BACKGROUND
  Bariatric surgery provides significant weight reduction; however, it may result in food intolerance followed by gastrointestinal complications that may lead to nutritional deficiencies. This study evaluated the influence of red meat intolerance on the dietary pattern, biochemical indicators, and clinical symptoms after Roux-en-Y gastric bypass (RYGB).
  
  
  METHODS
  This retrospective study evaluated patients 4 years after RYGB. The patients were divided into 2 groups: patients with and without red meat intolerance, and data for the following were collected: food intake, anthropometric data, biochemical data, and presence of nausea, vomiting, weakness, weak nails, and hair loss. The difference between groups in the times postoperative was determined by ANOVA.
  
  
  RESULTS
  Of the 72 patients included in the study, 63 were evaluated during the first postoperative year, 45 during the second, 56 during the third, and 41 during the fourth. Red meat intolerance was observed in 49.2%, 42.2%, 46.4%, and 39% of the patients after 1, 2, 3, and 4 years, respectively. After 1 year, the intolerant group showed lower calorie, carbohydrate, and iron intake. After 3 years, tolerant patients showed weight regain (2.9 ± 5.3 kg), while the intolerant ones remained stable. There was no difference in the presence of clinical symptoms or biochemical indicators between groups.
  
  
  CONCLUSIONS
  Red meat intolerance is frequent after bariatric surgery and may alter energy, iron intake, and weight loss; however, it is not associated with the presence of clinical symptoms and biochemical profile.
authors: Clinical Nutrition-Department of Internal Medicine, University of São Paulo, Ribeirão Preto, Brazil.
authors: Carolina Ferreira
authors: CF
authors: Nicoletti
authors: Clinical Nutrition-Department of Internal Medicine, University of São Paulo, Ribeirão Preto, Brazil.
authors: Bruno Affonso Parenti
authors: BA
authors: de Oliveira
authors: Clinical Nutrition-Department of Internal Medicine, University of São Paulo, Ribeirão Preto, Brazil.
authors: Renato
authors: R
authors: Barbin
authors: Clinical Nutrition-Department of Internal Medicine, University of São Paulo, Ribeirão Preto, Brazil.
authors: Julio Sergio
authors: JS
authors: Marchini
authors: Department of Surgery and Anatomy, University of São Paulo, Ribeirão Preto, Brazil.
authors: Wilson
authors: W
authors: Salgado Junior
authors: Clinical Nutrition-Department of Internal Medicine, University of São Paulo, Ribeirão Preto, Brazil. Electronic address: carla@fmrp.usp.br.
authors: Carla Barbosa
authors: CB
authors: Nonino
mesh_terms: D000328:Adult; D004032:Diet; D004435:Eating / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D015390:Gastric Bypass / Q000009:adverse effects*; D006801:Humans; D008297:Male; D009767:Obesity, Morbid / Q000601:surgery*; D011183:Postoperative Complications; D011184:Postoperative Period; D000069466:Red Meat; D012189:Retrospective Studies; D013997:Time Factors; D015431:Weight Loss / Q000502:physiology*
keywords: Bariatric surgery; Food intake; Gastric bypass; Protein intake; Red meat intolerance