I tend to think, like Mr Red, that wheat and dairy intolerance might be linked to humans not farming until relatively late in our evolutionary timeline.
It's obvious that early Man didn't till or harvest, or have herds of milking cattle. But what about rice? Most people can digest rice fairly easily, but that is a grain which has/had to be cultivated. And our much-loved spuds only arrived here in the 16th century. Yet they too are normally well-tolerated. My husband had never seen a potato in his entire life pre-UK, but loves them! Wheat is merely starch, so we could surely digest that with no trouble. It's milk with lactose that causes some folk problems, yet mothers have breastfed their babies from time immemorial...

olddude, since being told by the doc to avoid chocolate and runny cheese, I'm putting all my efforts into eating far more crumpets to make up the difference. It's hard, but I'm doing my best...