Experimental and Clinical Evidence on Anti-Inflammatory, Antioxidant, and Immunomodulatory Effects of Vitamin C: An Updated and Comprehensive Review Publisher



Kianian F ; Gholami A A ; Ghalibaf M H E ; Marefati N ; Boskabady M ; Boskabady M H
Source: Journal of Functional Foods Published:2026

Abstract

Vitamin C is one of the most widely used nutritional supplements that has attracted much attention due to its potential role in diseases related to oxidative stress, inflammation, and immune system disorders. This updated review reviews the findings from in vitro, animal, and clinical studies published from 2015 to the end of 2025 on the anti-inflammatory, antioxidant, and immunomodulatory effects of vitamin C. Available evidence suggests that vitamin C can reduce inflammatory responses by regulating the activity of inflammatory cells, cytokines, and cell signaling pathways, particularly nuclear factor kappa B (NF-κB)-dependent pathways. It also plays a role in maintaining the redox balance by reducing reactive oxygen species, nitric oxide-related damage, lipid peroxidation, and other markers of oxidative damage, as well as by enhancing endogenous antioxidant systems. In addition, vitamin C has disease-specific immunomodulatory effects, such that it can enhance some antiviral and antitumor responses while preventing excessive activation of immune cells in inflammatory conditions. Unlike previous reviews that have focused on specific diseases or a subset of vitamin C effects, this article comprehensively and integratedly reviews the available evidence, paying particular attention to the dose-response relationship, pharmacokinetic limitations, and the transferability of preclinical study results to clinical applications. Overall, vitamin C may be useful as an adjunct therapy in some diseases associated with inflammation, oxidative stress, and immune disorders, although its clinical efficacy depends on the disease state, initial vitamin C status, severity of inflammation and oxidative stress, dose and route of administration, timing of intervention, and therapeutic goal. Copyright © 2026. Published by Elsevier Ltd.