Lactose intolerance can lead to digestive upsets - those generally associated with Irritable Bowel Syndrome (IBS). Diarrhoea, wind, nausea is common.
The lactose intolerance diet can mean different things to different people. It depends on how sensitive you are to lactose, and whether the condition is hereditary (permanent) or acquired due to a gut infection (not permanent).
In most cases, cutting down on or avoiding sources of lactose and replacing them with lactose-free alternatives is enough to control the symptoms of lactose intolerance.
If you find that hard cheeses cause reactions, you may not be dealing with lactose intolerance, but rather an intolerance to amines.
gastro_lactose.pdf (QLD Health, lactose diet, foods to eat, foods to avoid)