I am lactose intolerant but have always taken Lactase supplements every time I eat milk, cheese or ice-cream (I don't have a problem with yogurt because of the natural bacteria that's in it.) This almost always helps unless I have a day where I eat an unusually large amount of dairy. I have also heard that Apple Cider Vinegar creates digestive enzymes so I've also been drinking about 1 tsp 2 times a day of ACV with juice. I don't think that is as effective as the lactase enzyme but it seems to help more than doing nothing. Also, my aunt says she can build a 'tolerance' to dairy - she will make sure to drink a little milk every day so she doesn't lose it.