Black Elderberry for Immune Function

Research suggests that dietary plant bioactives — the class of compounds that includes those found in black elderberry — may influence immune-related gut function by shifting how the gut microbiome operates metabolically, even when total fiber and macronutrient intake remains the same. A single small randomized crossover trial of 20 healthy adults found that a two-week high-bioactive diet increased gut microbial diversity and altered metabolite profiles in urine and stool more noticeably than it changed which microbial species were present, suggesting these compounds may primarily affect microbial activity rather than microbial composition. It is important to note that this study examined a broad dietary pattern rich in many plant bioactives and was not specific to black elderberry, so its findings cannot be directly attributed to elderberry alone. The overall evidence base here is very limited — consisting of a single small trial — and the authors themselves call for further research, meaning any conclusions about black elderberry's role in immune function via this mechanism remain preliminary at best.