Mannitol is a sugar alcohol that occurs naturally in certain fruits and vegetables, such as apples, pears, and mushrooms. It is commonly used as a low-calorie sweetener and is valued for its ability to retain moisture, making it useful in food products, pharmaceuticals, and cosmetics. With a sweetness level about half that of sucrose (table sugar), mannitol provides a sweet taste without significantly affecting blood sugar levels, making it a popular option for those managing diabetes. Additionally, mannitol is often used in medical settings as a diuretic to reduce intracranial pressure or to treat kidney conditions.