Ketogenic Diet for Preoperative Weight Reduction in Bariatric Surgery: A Narrative Review

Luca Colangeli; Paolo Gentileschi; Paolo Sbraccia; Valeria Guglielmi

doi:10.3390/nu14173610

Ketogenic Diet for Preoperative Weight Reduction in Bariatric Surgery: A Narrative Review

Nutrients. 2022 Aug 31;14(17):3610. doi: 10.3390/nu14173610.

Authors

Luca Colangeli^{1

2}, Paolo Gentileschi³, Paolo Sbraccia^{1

2}, Valeria Guglielmi^{1

2}

Affiliations

¹ Department of Systems Medicine, University of Rome Tor Vergata, 00133 Rome, Italy.
² Obesity Medical Center, Policlinico Tor Vergata, 00133 Rome, Italy.
³ Department of Bariatric and Metabolic Surgery, San Carlo of Nancy Hospital, University of Rome Tor Vergata, 00133 Rome, Italy.

Abstract

Bariatric surgery (BS) is the most effective treatment in reducing weight and the burden of comorbidities in patients with severe obesity. Despite the overall low mortality rate, intra- and post-operative complications remains quite common. Weight loss before BS reduces surgical risk, but studies are inconclusive regarding which is the best approach to apply. In this review, we summarize the current evidence on the effect of a ketogenic diet (KD) before BS. All studies agree that KD leads to considerable weight loss and important improvements in terms of surgical risk, but populations, interventions and outcomes are very heterogeneous. KD appears to be a safe and effective approach to induce weight loss before BS. However, randomized controlled trials with better-defined dietary protocols and homogeneous outcomes are necessary in order to draw firm conclusions.

Keywords: VLCKD; bariatric surgery; ketogenic diet; pre-operative weight loss; very-low-calorie ketogenic diet.

Publication types

Review

MeSH terms

Bariatric Surgery*
Diet, Ketogenic* / methods
Humans
Obesity, Morbid* / surgery
Treatment Outcome
Weight Loss

Grants and funding

This work was supported by a grant from the Ministero dell’Istruzione, dell’Università e della Ricerca (prot. 2017L8Z2EM) received by V.G. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.