Changes in Nutritional Outcomes After Sleeve Gastrectomy: a Systematic Review and Meta-analysis

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#calcium #folic-acid #gastrectomy #humans #iron

Changes in Nutritional Outcomes After Sleeve Gastrectomy: a Systematic Review and Meta-analysis

Wang et al., 2022 | Obes Surg | Meta Analysis

Citation

Wang Yan, Duan Leizhen, ... Yan Guoli. Changes in Nutritional Outcomes After Sleeve Gastrectomy: a Systematic Review and Meta-analysis. Obes Surg. 2022-Jan;32(1):103-114. doi:10.1007/s11695-021-05740-z

Abstract

PURPOSE: The aim of this meta-analysis is to evaluate the changes in nutritional indicators in individuals with obesity before and after SG. MATERIALS AND METHODS: A systematic retrieval of the available literature was performed using PubMed, Embase, Web of Science, and Chinese National Knowledge Infrastructure databases. The following indicators were evaluated: serum 25-hydroxyvitamin D [25(OH)D], calcium, phosphorus, iron, vitamin B12, folate, magnesium, and zinc from pre-operation to post-operation. RESULTS: A total of 38 studies met inclusion criteria. A significant increase was observed in serum 25(OH)D (SMD = 0.70, 95%CI 0.38 to 1.02, P < 0.001), phosphorus (SMD = 0.40, 95%CI 0.14 to 0.67, P = 0.003), iron (SMD = 0.50, 95%CI 0.38 to 0.62, P < 0.001), and folate (SMD = 0.37, 95%CI 0.09 to 0.65, P = 0.01) after SG. Nevertheless, the increasing trend of serum phosphorus (P = 0.143) and folate (P = 0.774) disappeared in the unprescribed subgroup. A significant decrease in serum zinc (SMD =  - 0.41, 95%CI - 0.81 to - 0.01, P = 0.044) was found after SG. No significant changes in serum calcium (SMD = 0.08, 95%CI - 0.09 to 0.25, P = 0.372), vitamin B12 (SMD = 0.10, 95%CI - 0.13 to 0.33, P = 0.398), and magnesium (SMD = 0.24, 95%CI - 0.10 to 0.58, P = 0.169) were observed. However, a significant decrease in serum calcium (P = 0.042) and vitamin B12 (P = 0.037) was found in the unprescribed subgroup. CONCLUSIONS: Serum 25(OH)D, phosphorus, iron, and folate levels improved after a careful monitoring and due to a rigorous supplementation. The optimal dose of calcium, magnesium, and zinc supplementation has yet to be established; therefore, a broader supplementation of trace elements and minerals has to be suggested.

Key Findings

A total of 38 studies met inclusion criteria. A significant increase was observed in serum 25(OH)D (SMD = 0.70, 95%CI 0.38 to 1.02, P < 0.001), phosphorus (SMD = 0.40, 95%CI 0.14 to 0.67, P = 0.003), iron (SMD = 0.50, 95%CI 0.38 to 0.62, P < 0.001), and folate (SMD = 0.37, 95%CI 0.09 to 0.65, P = 0.01) after SG. Nevertheless, the increasing trend of serum phosphorus (P = 0.143) and folate (P = 0.774) disappeared in the unprescribed subgroup. A significant decrease in serum zinc (SMD =  - 0.41, 9

Outcomes Measured

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Population

Field Value
Population obesity before and after
Sample Size 38
Age Range See abstract
Condition See abstract

MeSH Terms

  • Calcium
  • Folic Acid
  • Gastrectomy
  • Humans
  • Iron
  • Magnesium
  • Obesity, Morbid
  • Phosphorus
  • Vitamin B 12
  • Zinc

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Systematic Review
  • Vertical: magnesium

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09