Effective reduction of lactose maldigestion in preschool children by direct addition of beta-galactosidases to milk at mealtime.

We examined the efficiency of two beta-galactosidase preparations--one derived from the yeast, Kluyveromyces lactis (Lactaid), the other derived from the fungus, Aspergillus oryzae (Takamine)--to assist the in vivo digestion of lactose consumed by healthy Guatemalan preschool children. Milk prehydrolyzed by in vitro incubation with enzymes was used as the standard of reference, and the degree of incomplete digestion of lactose from 240 mL of milk was determined using the hydrogen breath test. In in vivo dose-response studies, both 3,250 neutral lactose units of Lactaid and 6,635 food and chemical codex lactose units of Takamine completely eliminated excess H2 excretion in a small sample of lactose-maldigesting subjects. When evaluated in a controlled, clinical trial setting, the same dose of Lactaid added directly to the milk at consumption produced an 82% relative reduction in H2 excretion, whereas Takamine was equally as effective as the prehydrolyzed milk. Thus, intraluminal conditions and gastrointestinal transit in the preschool child support the effective assisted digestion of milk lactose in an efficient manner and with the same enzyme to milk ratios as observed previously in adults.