Lactose is converted to glucose and galactose by yeast and bacteria during fermentation. In comparison to the initial lactose levels present in the milk, the fermentation reduces lactose levels by 20–30%. According to one study, when lactose-intolerant individuals ate the same amount of milk, kefir, or yoghurt products, the latter two displayed noticeably less lactose intolerance symptoms during the first eight hours Kefir. According to this finding, yoghurt and kefir may be suitable for those who are lactose intolerant. But no research has been done on how long-term kefir use affects lactose sensitivity. Additionally, it has been demonstrated that fermented milk products transit more slowly than milk, which may enhance lactose absorption.
