It's not typically harmful to humans, although you may want to avoid cooking your beans in hard water. These minerals can also make cleaning more of a struggle. Soap reacts the way you want it to in soft water. In hard water, parts of soap bond to some of those minerals and create soap scum, reducing cleaning power and leading to deposits that are especially visible on silverware and glassware.
It's simple: Spritz the broom with a cleaner before sweeping. When I asked her why, she shrugged and said, "It helps with the hair." Turns out, the reason it works has less to do with the hair itself and more to do with static electricity. Pet fur picks up static charges from rubbing against carpets, furniture, and fabric (or maybe that perpetually squashed dog bed). That's why it's so stubborn to sweep up.