3 53 Lactose intolerance Lactose intolerance causes diffi culty digesting dairy products that contain lactose milk sugar It is particularly common among people of African and Asian ancestry In the United States ignor ing other groups and people who consider themselves to belong to more than one race 82 of the popula tion is white 14 is black and 4 is Asian Moreover 15 of whites 70 of blacks and 90 of Asians are lactose intolerant 22 a What percent of the entire population is lactose intolerant b What percent of people who are lactose intolerant