Lactose is the natural sugar found in milk and dairy products. It is made of two sugars, glucose and galactose, and must be broken down by the enzyme lactase before it can be absorbed. Lactose intolerance occurs when the body no longer produces enough lactase, leaving some lactose undigested and causing symptoms such as bloating, gas, and cramps. Fermentation reduces lactose because bacteria consume some of it. Lactose-free milk is not sugar-free milk—the sugar remains in the