Nature's Way Horse Chestnut contains 20% aescin, a saponin that demonstrated abilities of supporting healthy blood circulation in the lower extremities. It has clinically shown to contract the veins and arteries in the lower legs that may help manage the symptoms of Chronic Venous Insufficiency (CVI). It also provides venous support for haemorrhoids and spider veins. visit us : http://www.tasmanhealth.co.nz/natures-way-horse-ch estnut/ for more details!!