Chestnuts are the fruit of the chestnut tree and can be peeled or eaten raw. It is often roasted particularly in winter time.
So can chinchillas eat chestnuts at all?
Lets take a look here and find out more. In particular, their acidic content, sugar, fat, calcium, and phosphorus content is of most interest as far as chinchillas are concerned.
As you can see chestnuts contain a little phosphorus, a hint of calcium, a lot of acidic content, and sugar.
With that chinchillas cannot eat chestnuts at all. They just have too much acidic content and sugar for chinchillas to handle. They will be ill if they eat them as their tummies just cannot handle them. A food to avoid.