Lactose-free Yogurts do not Show any Benefits for Lactose-Intolerant Subjects, Compared with Lactose- Containing Yogurts

Abstract

Nowadays, there is constant increase of commercial lactose-free yogurts for lactose-intolerant individuals. However, the real interest of these yogurts is unclear considering that several clinical trials have shown that the living bacteria present in the yogurt improved lactose tolerance in hypolactasic subjects, due to their s-galactosidase activity that remains functional in the small intestine of these individuals. The aim of this study was to determine whether the intake of lactose-free yogurt (LFY) is beneficial for hypolactasic lactose-intolerant subjects compared with that of traditional, lactose-containing yogurt (LCY). Twenty-two subjects with auto-reported digestive symptoms after milk consumption carried out a hydrogen breath test (HBT) with 25g lactose to confirm their hypolactasic status. Fourteen subjects (63.6%) who exhibit a positive HBT accompanied by digestive symptoms were finally incorporated to the study. In two independent days, they have to ingest, in a double-blind and randomized form, 250g of LFY or LCY. These products brought 0.5g and 19.8g of lactose, respectively and both exhibited total counts of lactic acid bacteria higher than 107 CFU/g. Changes in breath H2 excretion and digestive symptoms were registered during 180 min. When the volunteers carried out the HBT with LFY and LCY, no differences were detected in H2 excretion or the intensity of digestive symptoms (individual or total). Accordingly, our results suggest than the intake of LFY that are more expensive than LCY, does not bring any supplementary detectable benefits for the lactose intolerant subjects.