This is what makes poo brown:

Just FYI, for those of you who are interested:

There's a compound called heme that is carried in your red blood cells.  When the red blood cells die (a natural process), they are essentially broken down and the heme is released.  So you gene "free" heme floating around.  "Free" heme degraded to bilirubin.  The intestine interacts with bilirubin to make stuff called urobilinogen, which is metabolized by bacteria and eventually makes stercobilins.

Stercobilins are brown.  Hence, your intestines have a bunch of brown stuff in 'em.  Hence, you poop and it is brown.

How's that for enrichment?  HA!

 

Man, I really am becoming quite The Bore.  I am going over this stuff 92834 times trying to figure it out.  All these diseases and weird enzymes and their deficiencies.  It's amazing that anyone is relatively healthy out there. 

My mother said when she was in nursing school and they were going over the matneral/gynocological bits, she said she found every place where her OB/GYN went wrong. She said it was amazing he didn't manage to kill either one of us when she was in labor with me. Sometimes people survive, in spite of doctors!