1. Find out how many calories you roughly burn in a day (There are many calculators out there)
2. Eat food that you enjoy and stay under that calorie amount
Thats it.
That may work for you, stick with what works. I used to eat that way but prefer to eat larger meals. Eating small meals I would never be satisfied
Overall though the overall calories eaten is what matters. Doesnt matter if you eat them in 3 or 6 meals.
There has never been studies proving meal frequency increased metabolism, its all heresay
http://forum.bodybuilding.com/showthread.php?t=119024341
There is also a study where metabolism rate increased (6-10% IIRC) from short term (24-36hr) fasting
This^^ Just to add though its not just the whey protein, its all sources of it. But it usually doesnt cause problems, but it can make it worse if kidneys are failing