ABSTRACT
Secretory immunoglobulin A (s-IgA) in saliva constitutes the first-line barrier to the entry of pathogens into the body, implying its critical role in mucosal immunity.To examine the effect of a shark liver oil (SLO)-containing diet on salivary s-IgA concentration in healthy male and female adults, 42 subjects were assigned to either placebo or 6 weeks of a 2,400 mg SLO-containing diet (1,500 mg as SLO) and assessed in a randomized, double-blind, placebo-controlled, parallel group trial.Salivary s-IgA concentration significantly increased at week 6 in the SLO group (P = 0.033), but not in the placebo group.Moreover, there was a significant difference between groups in the magnitude of change from baseline to week 6.No intervention-related adverse event or abnormal changes of laboratory test parameters were observed throughout the study period.In conclusion, an SLO-containing diet increases salivary s-IgA in healthy adults.