The Effect of Bovine Colostrum Supplementation on Secretory Immunoglobulin A and Health Status in Middle-aged and Elderly people: A Double-Blind, Randomized, Controlled Trial

Background: The rapid population aging is becoming a serious health crisis. This study aims to evaluate the effects of bovine colostrum supplementation on enhancing Secretory immunoglobulin A and health in middle-aged and elderly people. Methods: A total of 188 persons aged 50 to 85 years participated in this 90-day randomized, double-blind, controlled trial and were randomly assigned to intervention or positive control groups. The intervention group received bovine colostrum (BC) supplement containing rich probiotics and whey protein, while the positive control group received regular milk powder, both twice a day. The primary outcome was the change in the concentration of saliva secretory immunoglobulin A. Results: There were 171 participants completed the trial. The concentration of saliva secretory immunoglobulin A increased in both groups（P 0.05). The level of serum immunoglobulin A in the intervention group was significantly higher than that in the control group (P 0.05). There were no differences in nutrient intake and physical activity between the two groups (P > 0.05). In self-reported health status, both groups showed significant improvements in sleep quality (P < 0.05). The incidence of oral ulcers decreased in total（19.7% vs 8.8%) (P < 0.01), and the reduction was significant in the intervention group (P < 0.05). Conclusions: The results showed that BC supplement powder intervention for 90 days may provide beneficial health care effects in middle-aged and elderly people and promote healthy aging, but the differences in the effects of BC supplement powder and ordinary milk powder on salivary sIgA need to be further studied.