From meal preparation, to when you sit down and eat a meal, the nutrients and vitamins have a long journey ahead before being absorbed into the body. When ingesting food the nutrient absorption rate is generally 50%, which leaves room for improvement. If you are not eating a balanced and well rounded diet getting the sustenance your body needs is even harder.
When you receive nutrients and vitamins intravenously they are injected into the bloodstream directly, bypassing the digestive system, maximising absorption of nutrients and vitamins, meaning immediate benefits.