LACTOSE MALDIGESTION - DEFINITION, PREVAL ENCE IN MEXICO AND ITS IMPLICATIONS IN MILK CONSUMPTION

We review the studies that have been carried out in Mexico related to prevalence of lactase deficiency. We also describe a study carried out in three regions of Mexico with different consumption of milk (Northe rn, Central & Southeastern), comprising 960 individuals of ages rangin g from 1 to 99 years. They were evaluated in a double blind study in o rder to determine the prevalence of lactose maldigestion with habitual dosis of milk. Each subject received two treatments: a) 240 or 360 mL of intact milk according to age, and b) the same amount of milk but w ith the lactose hydrolyzed (> 90% hydrolyzed). The participants were c lassified as digesters or maldigesters of lactose using the hydrogen b reath test. The prevalence of maldigesters was higher in the Central ( 30%) and Southeastern (22%) regions than;in the Northern one (9%, p < 0.01). The prevalence increased with age from 4.5% (< 3 years), 13.6% (3 to 5.9), 20.8% (6 to 12.9), 21.8% (13 to 17.9) and 32.9% in adults. Lactose maldigestion affected consumption marginally.