Lactose malabsorption in Mexican-American adults.

Lactose malabsorption was determined in 277 Mexican-American (MA) and 142 Anglo-American (AA) adults aged 18 to 94 years old, and correlated with nutrient intake assessed from 24-hr dietary recalls, as well as with milk and dairy product consumption. Lactose malabsorption occurred in 144 of 277 (53%) MA and 21 of 142 (15%) AA. Analysis of dietary questionnaires revealed no differences between lactose absorbers and malabsorbers within each ethnic group in their consumption of protein, calories, riboflavin, vitamin A, or calcium. Vitamin A, calcium, and riboflavin intake was greater in AA than in MA subjects. Milk and dairy product consumption was the same in lactose absorbers and malabsorbers in both ethnic groups. Nearly 60% of MA malabsorbers and 24% of AA malabsorbers recognized experiencing symptoms after milk ingestion. Although group differences in milk consumption on the basis of lactose absorption status are not apparent, individual lactose malabsorbers may alter milk ingestion in response to lactose-induced symptoms. Lactose malabsorption occurs in over half of MA adults and may in some individuals present a clinically relevant problem.