Glutathione Levels after Glutathione Supplementation: A Systematic Review and Meta-analysis

Peerawut Mangkalopakorn; Charnsiri Segsarnviriya; Monruadee Keeratipranon; Mart Maiprasert

doi:10.59796/jcst.V15N1.2025.90

Authors

Peerawut Mangkalopakorn Department of Anti-Aging and Regenerative Medicine, College of Integrative Medicine, Dhurakij Pundit University, Bangkok 10210, Thailand
Charnsiri Segsarnviriya Department of Otorhinolaryngology Head and Neck Surgery, Samitivej Thonburi Hospital, Bangkok 10600, Thailand
Monruadee Keeratipranon College of Integrative Medicine, Dhurakij Pundit University, Bangkok 10210, Thailand
Mart Maiprasert Department of Anti-Aging and Regenerative Medicine, College of Integrative Medicine, Dhurakij Pundit University, Bangkok 10210, Thailand

DOI:

https://doi.org/10.59796/jcst.V15N1.2025.90

Keywords:

glutathione, glutathione levels, glutathione supplementation

Abstract

Glutathione is a crucial antioxidant and plays a vital role in many biochemical processes within living organisms. Abnormal levels or reductions in glutathione are linked to various health conditions and diseases. While glutathione supplementation might offer health benefits, there are ongoing concerns about its low bioavailability. This research aimed to examine the effects of glutathione supplementation on body glutathione levels through a systematic review and meta-analysis of primary studies. Randomized controlled trials (RCTs) were selected from online databases, including PubMed, Scopus, Google Scholar, and Cochrane Library. The studies compared participants who received glutathione supplementation with those in placebo or control groups by evaluating their glutathione levels. The results showed that five primary studies met the inclusion criteria. The quality assessment revealed that most studies had a low risk of bias or some concerns in various areas. However, there was a high risk of bias related to the selection of reported results, primarily due to multiple measurements or analytical methods. Three articles were included in the meta-analysis, which found no statistically significant difference in glutathione levels in erythrocytes [Standardized Mean Difference: 0.74, 95% CI (-0.44, 1.91); P = 0.22] or plasma [Standardized Mean Difference: 0.44, 95% CI (-0.21, 1.09); P = 0.19] between the intervention and placebo groups. This study concluded that glutathione supplementation does not significantly increase glutathione levels in erythrocytes or plasma. However, higher doses and longer durations of supplementation may potentially lead to increased glutathione levels in the body.

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