Actually before college (age 25 - couldn't afford it earlier, couldn't afford it then - just went) I, like DG, read whatever was of interest. In college there was too much "structured" reading for course work that I fell out of the habit of reading non-fiction (well mostly) and what I read is for my own pleasure. Occasionally I read non-fiction - e.g. a very good book IMHO is "Brain Sex - The real difference between men & women" by Dr. Anne Moir & David Jessel.
I highly recommend it, even if Patricia
might (???) call it bad science as she did about plants feeling. I found it quite interesting.