Keywords:
gastric bypass
macronutrients
anemia
nutritional management

  • Abstract

    Bariatric surgery has emerged as the most effective and reliable intervention for managing morbid obesity, offering sustained weight loss, reduced mortality rates, and significant improvements in overall quality of life. Studies demonstrate a 42% reduction in cardiovascular mortality and a 30% decrease in all-cause mortality following these procedures. Despite its success, bariatric surgery is associated with significant nutritional challenges that must be addressed to ensure long-term patient health and well-being. This review focuses on the critical need for comprehensive preoperative evaluations to identify and manage existing nutritional deficiencies in patients undergoing bariatric surgery. Nutritional deficits, such as deficiencies in iron, vitamin B12, calcium, and fat-soluble vitamins, are common and can lead to severe complications, including anemia, osteoporosis, and neurological impairments. Additionally, post-surgical syndromes like reactive hypoglycemia and dumping syndrome, arising from altered gastrointestinal anatomy and function, require targeted dietary management. The review also examines the differences in deficiency risks across various bariatric procedures, highlighting that malabsorptive procedures, such as Roux-en-Y gastric bypass (RYGB) and biliopancreatic diversion (BPD), pose greater risks compared to restrictive procedures like sleeve gastrectomy (SG). A multidisciplinary approach that includes preoperative nutritional assessments, tailored dietary plans, lifelong supplementation, and regular monitoring is essential to prevent and manage these complications. Ultimately, this review emphasizes the importance of proactive nutritional care in enhancing the outcomes of bariatric surgery and ensuring long-term patient success. Addressing these challenges is crucial for minimizing post-operative risks and improving the quality of life for bariatric surgery patients.

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Nakshine, V., & Keoliya, A. (2025). Addressing nutritional challenges in bariatric surgery patients from preoperative assessment to long-term outcomes. Multidisciplinary Reviews, 9(1), 2026035. https://doi.org/10.31893/multirev.2026035
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