Yu Xue (瘀血) blood stasis syndrome is a common pathogen and pathogenic consequence ((Ko MM, Cha MH, Jung J. Association of serum resistin with blood stasis syndrome in traditional Korean medicine for metabolic diseases: a cross-sectional multicenter observational study. in press. https://doi.org/10.1016/j.imr.2021.100719 )). It is commonly seen after traumatic damage, bleeding, Qi stagnation, and chronic diseases. A research team from Korea observed 885 patients and found that the levels of serum resistin were significantly correlated with symptoms of the blood stasis syndrome, especially dark red gums, dark facial complexion, and nocturnal pain.