Abstract
- Background
While in vitro and animal studies have demonstrated that Chlorella acts as a potent biological response modifier supporting immunity, direct clinical evidence regarding the effects of Chlorella supplementation on human immune and inflammatory responses remained limited. This study was designed to investigate the immunological impacts of short-term Chlorella supplementation in healthy human subjects.
- Methods
An 8-week randomized, double-blind, placebo-controlled trial was conducted involving participants randomly assigned to receive either 5 grams of Chlorella daily ($n = 23$) or a matching placebo ($n = 28$) in tablet form. The primary immunological evaluations measured the cytotoxic activities of Natural Killer cells alongside serum concentrations of key regulatory cytokines, including interferon-gamma, interleukin-1 beta, and interleukin-12.
- Results
Following the 8-week intervention, serum concentrations of interferon-gamma ($P < 0.05$) and interleukin-1 beta ($P < 0.001$) significantly increased, while interleukin-12 showed a strong upward tendency ($P < 0.1$) in the Chlorella group, with net increments significantly greater than those observed in the placebo cohort. Furthermore, Natural Killer cell cytotoxic activities significantly increased in the Chlorella group but remained unchanged in the placebo group. Correlation analyses revealed significant positive associations between changes in Natural Killer cell activity and alterations in serum interleukin-1 beta ($r = 0.280$, $P = 0.047$) and interferon-gamma ($r = 0.271$, $P < 0.005$), alongside strong positive correlations among the shifts in the evaluated Th1-induced cytokines.
- Conclusions
Short-term Chlorella supplementation exerts a beneficial immunostimulatory effect in healthy individuals by enhancing Natural Killer cell cytotoxic activity and promoting the production of key Th1-induced cytokines, including interferon-gamma, interleukin-12, and interleukin-1 beta.
https://pmc.ncbi.nlm.nih.gov/articles/PMC3511195/