In my experience, you can sort of increase your lactose tolerance ability by drinking small amounts of milk everyday, and slowly increasing the amount of milk. My theory is that the bacteria in your digestive system primarily responsible for ingesting lactose will slowly increase in population, allowing you to ingest it.

On the other hand, is it really worth it? I've heard that milk drinkers have higher risk of cancer, because we're not really supposed to be drinking milk as ADULTS.