lactose intolerance, a sensitivity disorder resulting in the inability to digest lactose from milk products because of an inadequate production of or defect in the enzyme lactase. Symptoms of the disorder are bloating, flatus, nausea, diarrhea, and abdominal cramps. The diet is adjusted according to the tolerance level; milk-derived foods (milk, cheese, butter, and margarine) and any products containing milk, such as cakes, ice cream, cream soups, and sauces, are restricted. Also called milk intolerance. See also lactase deficiency.
