The entire plant is used medicinally. The root is eaten dried or cooked. Root tea (1/2 ounce to 1 pint water) is a folk remedy for pneumonia, whooping cough, asthma, bronchitis, upset stomach, diarrhea, and worms. It is said to kill tuberculosis bacteria. It is antibacterial, antifungal, and expectorant. It is used in China for certain cancers. It was used by gypsies to control horses, and it stimulates the immune system in animals. In studies of mice, the root tea had pronounced sedative effects. In small doses it lowers blood-sugar levels, but in larger doses it raises it. Roots contain 20 to 44 percent inulin, a dietary fiber that is recommended for leaky gut syndrome. It traveled across America with the pioneers. It is named after Helen of Troy who was said to be collecting it when she was abducted.