Here's a factoid with something funny my friend said. The human body is made up of between 60-75% water. More when you are a newborn, and decreasing gradually as you age. That's probably why you get all wrinkly as you get older.
I was explaining this to my friend and she demanded to know, "So if we both have roughly 65% of our bodies as water, how come my water weighs so much more than yours?"