Breast milk composition in Ethiopian and Swedish mothers. IV. Milk lipases.

The (potential) activities of the two lipases in human milk were determined in breast milk samples collected from Ethiopian and Swedish mothers. The major lipase in human milk is dependent on bile salts for activity and probably participates in intestinal digestion of milk lipids in the newborn. The level of this lipase in the milk did not change with time after parturition, but differed between the groups so that it was higher in the privileged Ethopian mothers than in the nonprivileged Ethiopian mothers, who in turn had a higher level than the Swedish mothers. The other lipase is a serum-stimulated lipase (lipoprotein lipase). The level of this lipase varied between samples from different mothers as well as between different samples from the same mother. It tended to be lower in samples obtained at 4 to 5 days after parturition (Swedish mothers) than in later samples. There were in this case no significant differences between nonprivileged and privileged Ethiopian mothers or between them and Swedish mothers.