We are what we eat: literally. Our bodies are, essentially, a bunch of carbohydrates with a few minerals and stuff thrown in for good measure. Where does it all come from? Your food, is where. Our food is basically just carbohydrates and minerals and so forth. So, we are what we eat. QED.
The same principle applies, not just to our bodies, but to our minds and spirits, too.
Mentally, we are the product of our learning, of the intellectual fare we have consumed. Of course, food doesn’t do you any good of it is left in the plate. Which is why, I suppose, my degree was a 2.2 instead of a 2.1.
Interestingly, the same thing works spiritually, too. Which is, I guess, why Jesus called himself the Bread of Life.
Excuse me, I must go and get a sandwich.