Wang, H.R. , et al. Therapeutic and tonic effects of Jiaogulan in leukopenic patients. Xin Zhong Yi. China, 1991

White blood cells are the body’s main defense against infectious disease so higher white blood cell counts (WBC) are strongly associated with the body’s ability to resist illness. In this study study leucopenic (white blood cell deficient) patients were given gypenosides (the clinical name for the active components of the herb gynostemma pentaphyllum) for one month. The average patient doubled their WBC during this time.