I can't do yoga on an empty stomach.
However, it is recommended that one doesn't eat a whole meal right before yoga class. It is recommended that one stops eating a 2-3 hours before your practise and stop drinking water 1 hour before.
These recommendations are based on a few things in my opinion:
You don't really want your stomach to be using your bodies energy for digestion, but rather for your practise.
It won't be fun to do your practise on a full stomach. You may get nauseous, or dizzy. You also don't want unwanted bodily functions to be happening while you are practising.
Life gets crazy sometimes though! There have been so many times when I have an afternoon yoga class and I realise two hours before that I hadn't eaten enough food to give me energy for my practise.
Here are a few tips on what to eat 2 hours before (I pick one or two of these at most, really just enough to get me through the next few hours):
Let me know if you have any more yummy suggestions!