diuretic, also known as a water pill, is something that makes a person urinate more often, increasing the rate at which water and salt leave the body. For those who want to lose weight but find that the body retains water, a diuretic helps alleviate this problem. There are many different types of diuretics that work in different ways, but all result in an increase in water loss during urination. Diuretics are not only used for weight loss, but can also be used for a number of medical conditions, including high blood pressure, edema, and high blood pressure. Although diuretics can help with water weight loss, they can also have other health benefits.