ADAPTATION OF LACTOSE MALDIGESTERS TO CONTINUED MILK INTAKES

Twenty-five lactose-maldigesting and lactose-intolerant African Americ ans, ranging in age from 13 to 39 y, were given gradually increasing a mounts of lactose in milk over a period of time until the maximum lact ose dose tolerated was determined. Seventeen (77%) of the 22 subjects who completed the study tolerated greater-than-or-equal-to 12 g lactos e and 5 (23%) tolerated < 12 g. Breath-hydrogen tests done on each sub ject with the maximum dose of lactose tolerated showed that only four (18%) had a breath-hydrogen concentration < 5 ppm above fasting concen tration. This study suggests that the majority of African-American you ng adults who claim intolerance to moderate amounts of milk can ultima tely adapt and tolerate greater-than-or-equal-to 12 g lactose in milk (the equivalent of 8 oz of full-lactose milk) with minimal or no disco mfort if milk is ingested in gradually increasing amounts. The mechani sm of adaptation is assumed to be an increased tolerance to colonic la ctose-fermentation products.