Most people usually consume vitamins and minerals through food; some people may also take additional multivitamin supplements. When vitamins and minerals are ingested orally, they enter the stomach and intestines, where they are broken down by enzymes in the gastrointestinal tract and then absorbed into the blood. There is a limit to the rate of absorption of these substances from the gastrointestinal tract; what is not absorbed continues to enter the body and is excreted in the feces. In addition, most of the substances absorbed from the gut pass through the liver for further processing before reaching the rest of the body. Other factors that affect the number of vitamins absorbed from the gut are a person’s metabolism, age, genetics, and interactions with other orally consumed foods. Ultimately, a significant portion of orally taken vitamins and minerals is lost, and only a small amount reaches the rest of the body. Since most of the vitamins and minerals are lost, the body does not get the full benefit of these substances when taken orally in the form of food or other supplements. With iv drip therapy, minerals and vitamins are introduced into the body through the veins. With this method of administration, vitamins and trace elements avoid metabolism in the intestine. In addition, substances enter the bloodstream faster and are distributed throughout the body, since they are not limited in absorption rate, as is the case with oral administration. Ultimately, only small amounts of vitamins and trace elements are wasted during intravenous vitamin therapy; most of it is absorbed and used by the body. Thus, the body receives all the benefits of vitamins and trace elements when administered through the veins, and not through the mouth.