Asked by: Mike Boucher, Manchester
Your body is constantly making, altering, and destroying chemical compounds, but they’re so varied and complex that it’s impossible to detect and count them all. Water is the most common, but the count will be dominated by long sugar molecules, proteins, RNA, and DNA. At a minimum, there are probably at least as many different chemicals as there are nucleated human cells in the body (about five trillion, not counting the tens of trillions of bacteria in the gut). I say that mainly because mutation means DNA molecules in one cell are likely to differ from those in others.