Whey protein is a pretty unknown subject by a lot of people. You ask someone about whey protein and they either do not want anything to do with the stuff, use it wrong, or do not maximize it's full effect. While it's true, you should get most, if not all of your protein intake from your diet, whey protein can actually be a very valuable asset in muscle building and fat burning. They key is when and how you use it. Whey protein is one of two different kinds of protein found in milk. Of the two proteins whey is quicker absorbing than its partner, casein. When looking for a “protein powder”, you have to remember that they are all created equal.
While almost all the protein powders out there do have a good amount of whey protein in them, ones that are considered weight gainers or are not a “whey protein isolate” typically have high amounts of carbs and fats in them as well. So when you are reading the backs of the powders make sure you are looking into the carbs and fats as well so you do not end up with a product not suited for your goals. In fact even if you wanted to gain weight, I still would not suggest getting any “weight gainers” because a lot of the time you get fat instead of bigger and leaner. Instead stick with the whey protein isolate and time it properly for full anabolic effect. Right before a workout, stick with eating a lean protein, like some chicken or turkey breast, along with fruit as your carb intake.
After your workout is when you want to take your whey protein isolate, again along with a fruit for the carb effect, this time for a completely different reason. The carbs you consume before a workout are used for fuel, it just enough to give you that initial burst and keep you going during the workout. AFTER a workout though, the carbs that you eat will work in a more anabolic (muscle building) way. The reason carbs give you energy is because of the sugar contained in them, we all know this. But what most people do not know is the fact that the insulin spike that the sugar causes is actually anabolic, meaning when your insulin levels in your blood spike, it allows the protein to be shuttled into the muscle more readily. Therefore, you use more of the protein you consume, speeding up the recovery and building process.
A popular concept of whey protein is that if you drink it, you gain huge amounts of muscle. Let me just say, whey protein is NOT testosterone. If a woman drinks whey protein, she's not going to look like Ronnie Coleman (8x Mr. Olympia). Whey protein is simply a tool that will help with the RECOVERY of the stresses and tears that occurs during a workout. Any sort of sizeable muscle gain is going to be from a lot of eccentric / negative work as well as how much testosterone you have available in your body at the time. It goes the other way around too for those guys who want to gain weight. Drinking 8 protein shakes a day is not going to get you looking like Ronnie Coleman either, your more likely to look like Jabba the Hut.
You might be able to use more whey protein but without your workout is that intense (assuming that you ARE working out and not just hoping that this is a magic drink), you probably do not need that many shakes a day. Stick with a pretty strict diet and timing everything to make the most of everything you do to get to your goals and keep kicking your butt in the gym and you'll get to where you want to be.