Horsetail (Equisetum arvense) is an herbal plant whose use dates back to ancient Roman and Greek times. It is known for its diuretic effect and ability to support bone health thanks to its high silicon content. The silicon in horsetail helps increase bone strength, so it is used in the treatment of osteoporosis. In addition, horsetail has antioxidant properties that may help inhibit the growth of cancer cells and support the treatment of kidney problems.