Traffic Lights for Food?

Mark Bittman wants “traffic light” labeling on food. Maybe XKCD's traffic lights are most appropriate.

In view of the fact that there is no objective definition of “Foodness” or “Welfare” (even “Nutrition” changes every decade), when Mark Bittman says:

These are not simple calculations, but neither can one honestly say that they’re impossible to perform.

he's just plain wrong.

We can imagine a manufacturer of freeze-dried potatoes being taken away in handcuffs for giving his product a high “Foodness” rating, followed by the revelation that freeze-dried potatoes were an Incan recipe.