Hemoglobin is an iron-containing protein in red blood cells that transports oxygen from the lungs to tissues in exchange for carbon dioxide.
Herbs are typically defined simply as plants that do not have a woody stem. Herbal preparations are compounds produced from herbs that are thought to have medicinal or nutritional properties. Many herbs and their preparations are marketed as potential ergogenic aids as well as for other health properties. Most of these claims are unfounded, yet the sale of herbs remains big business.