Do any of your colleagues have "fag breaks"? Tell your boss you're going for a "protein break"
All none smokers
I don't understand why your boss would have a problem with you eating at your desk if it doesn't effect your work? I don't take a lunch break and just eat my food as and when at my desk where ever I'm working - even if the customer thinks I eat too much
He has a problem because he doesnt do it and neither does anyone else.
It's a policy here that no food is to be consumed at your desk.