The review examines the effects of citrus fruit juices and their bioactive ingredients on inflammatory processes and the immune system. The focus is particularly on vitamin C and flavonoids such as hesperidin, naringin and narirutin. The authors show that citrus components have antioxidant, anti-inflammatory and immunomodulating properties.
Several experimental and clinical studies indicate that citrus flavonoids can inhibit pro-inflammatory signaling pathways such as NF-κB and reduce the production of pro-inflammatory cytokines such as TNF-α, IL-1β and IL-6. At the same time, vitamin C and phytochemicals support the function of various immune cells, including neutrophil granulocytes, macrophages and natural killer cells.
It is also described that citrus fruits can reduce oxidative stress and thus reduce inflammation-related tissue damage. The authors also discuss potential positive effects in chronic inflammatory diseases and respiratory infections.
The study concludes that citrus fruits and their juices as functional foods can make a relevant contribution to supporting immune function and reducing chronic inflammatory processes. At the same time, it is emphasized that further high-quality human studies are needed to better define dosages and long-term clinical effects.
Background
Chronic low-grade inflammatory processes are considered to be the main cause of numerous diseases of civilization, including cardiovascular diseases, type 2 diabetes mellitus, obesity and neurodegenerative diseases. At the same time, oxidative stress plays a central role in the development of inflammatory tissue damage. Citrus fruits contain a large number of bioactive ingredients with potential health-promoting effects, including vitamin C, flavanones, carotenoids and phenolic compounds.
Against this background, the review examines the current scientific findings on the anti-inflammatory and immunological effects of citrus fruits and citrus juices.
Methods
The authors conducted a narrative literature review of experimental, preclinical and clinical studies. Studies on citrus juices and isolated ingredients such as hesperidin, naringin, narirutin and vitamin C were considered.
In particular, the following were analyzed:
- antioxidant effects,
- Influences on inflammatory signaling pathways,
- Effects on cytokine formation,
- Effects on innate and adaptive immune responses,
- Potential applications in inflammatory and respiratory diseases.
Results
The studies analyzed show consistent antioxidant properties of citrus components. Vitamin C and flavonoids can neutralize reactive oxygen species and thus reduce oxidative stress.
Several studies show an inhibition of central inflammatory signaling pathways such as NF-κB and MAPK. At the same time, a reduced formation of pro-inflammatory mediators such as TNF-α, IL-1β and IL-6 has been described.
In addition, various studies show positive effects on immune cells. Vitamin C supports the function of neutrophil granulocytes, improves chemotaxis and phagocytosis and protects immune cells from oxidative damage. Flavonoids also influence the activity of natural killer cells and adaptive immune mechanisms.
Several studies also suggest that citrus components reduce excessive inflammatory reactions and may therefore contribute to the prevention of chronic inflammatory diseases.
Conclusion
The study evaluates citrus fruits and their bioactive ingredients as promising natural components for supporting the immune system and modulating inflammatory processes. The observed effects are presumably based on a synergistic interaction of various antioxidant and anti-inflammatory substances.
However, the authors emphasize that a significant proportion of the findings to date come from cell and animal models. Further controlled human studies are required to determine clinical relevance, optimal dosages and long-term effects more precisely.