One of the most terrifying stories I've heard is about some friends of my grandparents. The mother would cook bread, every day, for the family. She did this for years. Eventually, the dad became ill and died of cancer, then the mother, then the rest of the family. It was traced to some of these molds in the flour some time before the last one passed.

I also make bread, and you can be sure that I keep it in a dry place and make sure it smells fresh whenever I use it, even though I have no idea if moldy flour has a smell.