Lactose intolerance is the inability to digest lactose, the main sugar found in milk and dairy products. Lactose intolerance is caused by a shortage of the enzyme lactase, normally produced by the cells that line the small intestine. Lactase breaks down milk sugar into simpler forms that can then be absorbed into the bloodstream. A shortage of lactase makes it difficult for the body to digest lactose, resulting in nausea, cramps, bloating, and gas. Fifty million American adults are lactose intolerant. Luckily, lactose intolerance is easy to treat with over-the-counter products that contain lactase, such as Lactaid.
