From my Nutrition Now textbook:
"When did I start eating clay? I know it might sound strange to you, but I started craving clay in the summer of '58. It was a beautiful spring morning- it had just rained. I smelled something really sweet in the breeze coming in my bedroom window. I went outside and knew instantly where the sweet smell was coming from. It was the wet clay that lies all around my house. I scooped some up and tasted it. That's when and how I started my craving for that sweet-smelling clay. I keep some in the fridge now because it tastes even better cold."
Pica- the regular consumption of nonfood substances such as clay or laundry starch.
A list of nonfood substances reported to be consumed by individuals with pica:
Now if that isn't food for thought I don't know what is!