Lactose intolerance is a condition in which people are unable to completely digest lactose. Lactose is the sugar that is found in milk. Being lactose intolerant causes a number of embarrassing and uncomfortable symptoms such as gas, bloating, and diarrhea after eating or drinking dairy products. Lactose intolerance may also be known as lactose malabsorption. There are no serious complications associated with the condition and the symptoms can be managed. There are millions of people in the United States who have some degree of lactose intolerance.