Yeah, there is some formula but I am not sure what it is. As a result of reading up on protein requirements I have set myself a strict minimum of 45g per day. But I try to favor foods that give as much protein as possible for the calories they hold - which usually puts me quite a bit above 45g. I am a vegetarian, that's why I have to watch the protein so carefully. If you eat meat and fish, and do so most days, I doubt if you need worry about not getting enough, or even bother to track it.
