Effect of oral administration of freshly pressed juice of Echinacea purpurea on the number of various subpopulations of B- and T-lymphocytes in healthy volunteers: Results of a double-blind, placebo-controlled cross-over study

Conclusion: Oral administration of EPP for 1 and 2 weeks has only minor effects on two out of 12 lymphocyte subpopulations determined in the study. The small differences observed in the number of CD8+-T lymphocytes and natural killer cells are only of questionable physiological relevance.