Red root, most commonly referring to Ceanothus americanus (also known as New Jersey Tea), has a history of use in North American traditional herbal medicine, especially among Native American groups and 19th-century herbalists. It has been used as a blood purifier, lymphatic stimulant, and for conditions thought to involve stagnation in the blood or lymph, including "poor circulation." Historical texts and ethnobotanical records document its use in teas and decoctions for ailments like swollen glands, tonsillitis, and as a general tonic, but often without clear differentiation between lymphatic and circulatory systems as understood in modern medicine. There is little to no clinical or pharmacological evidence from modern scientific studies to support its efficacy for improving blood circulation specifically. Some laboratory studies have identified the presence of alkaloids, tannins, and other compounds, but these investigations have focused more on antimicrobial or antioxidant activity rather than circulatory effects. The rating reflects that while there is a tradition of use related to blood and lymphatic issues, this is not robustly substantiated by modern evidence, and its role in directly supporting or treating poor circulation remains largely anecdotal and unproven by rigorous research.