Broccoli is from the cabbage family and is an edible green plant that has a large flowering head. It has a large flower head which is usually green in colour that is arranged in a tree-like structure on branches that sprout from a thick, edible stalk. The flowerheads are surrounded by leaves.
So can chinchillas eat broccoli at all?
Lets take a look at its nutritional data and find out more. In particular, its calcium, sugar, calcium, fat, and phosphorus content are of most interest.
As you can see, broccoli contains quite a lot of calcium and a lot of of phosphorus and acidic content.
This means that chinchillas cannot eat broccoli at all. It will make them sick if they eat it as they just cannot handle its acidic content amongst other things. So keep it well away from them.
Image "Broccoli and cross section edit" by Fir0002 - Own work. Licensed under GFDL 1.2 via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:Broccoli_and_cross_section_edit.jpg#mediaviewer/File:Broccoli_and_cross_section_edit.jpg