Water, sugar, and salt are all necessary for the body to operate properly. Intravenous fluids (abbreviated "IV" fluids) are liquids administered to replace water, sugar, and salt that you may require if you are unwell or having surgery and are unable to eat or drink regularly. These fluids are essential for maintaining adequate blood volume and hydration, which is vital for normal functioning of the body's organs. Drinking enough fluid is particularly important for people who do not consume much food, such as those who are seriously ill or recovering from an operation. Being dehydrated can lead to confusion, headaches, poor memory, and other problems. Drinking enough fluid also helps to prevent urinary tract infections, constipation, and diabetes. People who are severely malnourished or have lost a large amount of blood may require alternative sources of nutrition. These individuals would typically receive nutrients directly into their bloodstream through an intravenous tube placed in one of their veins. This is usually done during emergency situations when oral feeding isn't possible. The nutrient solution is called parenteral nutrition and is given by injection. Nutrients that can be given orally must first go through a digestion process in the stomach and small intestine. This means that they will not be absorbed as effectively into the blood stream and may even cause some problems instead.