when you say you;re on a diet..do you mean diet as in trying to lose weight or diet as in "this is my eating habit"?
Cause there's no way you're dieting off fat at 5000 cals a day at 200 lbs.
So, because there's NO WAY that can be the case, then you must be asking about calories when on gear...well..
I say eat at your bodyweight x16, which is only 3200 cals and you're already at 5000..Well, I personally need more info on what you're really doing here on this diet you're on now, are you putting on any fat or what? If so, then I'd say drop to like 3500 cals while on the juice. I know I know, if you tell people at the gym you're only taking in that much, they'll be like "geez I'm not even taking anything and I eat like 9000000 calories a day and look at me!!" (and they will flex and look pathetic because they're the type who is at 60% bodyfat, but they can bench 300 so they are cool or something..so pay no attention to them.) I would also say to try a 40-30-30 ratio.
I'm sure someone more knowledged about this than I am will get back to you before I do anyway.