Metabolic Impact of Bariatric Surgery

Authors

  • Celso Nabais Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal https://orcid.org/0000-0002-5885-6931
  • Nuno Borges Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal https://orcid.org/0000-0001-6861-7929
  • Leonor Manaças Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal
  • Sara Vaz Rodrigues Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal
  • Inês Rego de Figueiredo Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal; Egas Moniz School of Health and Science, Almada, Portugal https://orcid.org/0000-0002-6492-7185
  • Anjum Dhanani Serviço de Cirurgia, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal https://orcid.org/0009-0005-9831-1652
  • Filipa Paula Serviço de Cirurgia, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal
  • João Oliveira Torres Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal; Serviço de Endocrinologia, Diabetes e Metabolismo, ULS São José, Lisboa, Portugal; Faculdade de Medicina da Universidade de Lisboa, Lisboa, Portugal; NOVA Medical School, Lisboa, Portugal https://orcid.org/0009-0003-5437-7567
  • José Silva-Nunes Serviço de Endocrinologia, Diabetes e Metabolismo, ULS São José, Lisboa, Portugal; Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; NOVA Medical School, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal https://orcid.org/0000-0002-4728-1220
  • António Albuquerque Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal https://orcid.org/0009-0005-6589-5348
  • Anabela Guerra Centro de Responsabilidade Integrado do Tratamento Cirúrgico da Obesidade, ULS São José, Lisboa, Portugal; Centro Académico Clínico de Lisboa, Lisboa, Portugal

DOI:

https://doi.org/10.34635/rpc.1134

Keywords:

Bariatric Surgery, Biomarkers/metabolism, Diabetes Mellitus, Type 2/surgery, Gastrointestinal Microbiome, Ghrelin/ metabolism, Glucagon-Like Peptide 1/metabolism, Obesity/surgery

Abstract

Bariatric surgery is the most effective intervention in the treatment of obesity, allowing sustained weight loss, high rates of type 2 diabetes remission, and reduced cardiovascular risk and mortality. This review discusses the main surgical techniques and outlines the associated metabolic gains, which begin shortly after surgery and are maintained in the long term. The related pathophysiological mechanisms, which go beyond the classically described restriction and malabsorption, are briefly explained in this article and include proximal bowel exclusion, early arrival of nutrients in the distal bowel, neuroendocrine and appetite-regulating hormone modulation, and changes in bile acid metabolism and the gut microbiome. In conclusion, it is essential to emphasize that the choice of surgical technique must be individualized, considering the metabolic outcomes it can provide, the risks of surgical and nutritional complications, and always within the context of a multidisciplinary program.

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Published

2026-02-08

Issue

Vol. 59 (2026): Supplement 1: Bariatric and Metabolic Surgery

Section

Review Article

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