Category Description: Protein is one of the three major, or macro, nutrients. Unlike carbohydrates and fats (the other two types of macronutrents), proteins are comprised of nitrogen-containing groups called amino acids. There are about 20 different types of amino acids commonly found in foods. All of them are important for building and maintaining muscle, but 8 are vital. These are what are known as the Essential Amino Acids (EAAs). Contrary to what most athletes believe, there is no actual requirement for protein; the body simply has a requirement for the eight essentials.
The EAAs cannot be synthesized in any of your tissues, so they must be obtained through high protein foods. Lean meats, fish, poultry, eggs, milk, cheese, and soybeans are good food sources of protein. Powdered whey, casein, egg, and soy proteins offer the same amino acids as whole food sources in more concentrated doses - with lower levels of calories, fat, carbs, cholesterol, and other non-protein ingredients.
Whey proteins are quickly and easily digested (hence the "fast-acting" description that they're often given), they are loaded with essential amino acids (EAAs) - including the three branched chain amino acids (BCAAs), and they contain subcomponents (microfractions) that appear to provide benefits above and beyond amino acids and elemental nitrogen. Whey is one of two major dairy proteins and accounts for about 20% of the protein in milk.
Comprising 80% of the protein in milk, casein is the dominant dairy protein. Oft referred to as a "slower-acting" or "time-released" protein, because they are digested and absorbed much more slowly than whey or soy proteins. Casein proteins are especially useful when taken at bedtime and during other prolonged periods without eating.
Milk proteins are pretty much what you'd expect: dried milk with most of the fat and carbohydrate removed. Like liquid moo juice, powdered milk proteins are about 20% whey protein and 80% casein protein, so utilization is somewhere in between the two.
Ask any dietician, "What's the best source of protein?" and eggs will probably top the list. In fact, most nutrition textbooks still refer to eggs as the "gold standard" for protein quality. With loads of essential amino acids (EAAs) and some of the highest scores in all measures of protein quality, we're not going to argue. Naturally dairy-free, eggs are a great alternative to whey, casein, and whole milk proteins for those with milk allergies or severe lactose intolerance.
Like their animal counterparts, soy proteins contain all of the required amino acids in sufficient amounts to support muscle growth and development.
If you can only afford one type of protein, this is probably the type that you should go with. Combining faster-, intermediate-, and slower-protein sources in one convenient place, blended proteins give you more sustained protein digestion than single-source proteins like whey, casein, egg, or soy.
CHOOSING A PROTEIN POWDER
Ask yourself, "What am I trying to accomplish?"
You can't start working toward your goals until you know what they are. Are you looking to get fit and build muscle? Add size and strength? Lose weight and stay lean? Whatever the case, the products that you select should be consistent with your objectives.
Figure out how much you need
For most individuals, 1 gram of protein per pound of bodyweight per day is a good target. Those who are looking to add size may need as much as 1.5 grams of protein per pound of bodyweight per day. You should also plan on eating some extra protein (1.25-1.5 g/lb/day) if you're trying to lose weight on higher-protein, lower carbohydrate diets, as some of the amino acids will be burned for fuel. In any case, this amount includes all of the protein that you consume through foods, beverages, and supplements. What's more, your daily protein allotment should be spread out over 4-6 smaller meals throughout the day for better absorption and utilization. If you're a big meat, fish, poultry, egg, and dairy food eater, you can probably get by with a smaller "hit" of protein from your powdered mix. Vegetarians and others who eat lots of starchy foods will benefit more from a higher-protein formula.
Determine what your budget & schedule allow
Single-source proteins offer more precise benefits. Ideally, you might use a fast-acting whey protein first thing in the morning and 30 minutes before workouts, a recovery product containing protein plus carbohydrates immediately after workouts, a moderately-digested egg or soy protein in between meals, and an all-casein protein at bedtime for sustained amino-acid delivery throughout the night while you sleep. Now, here's where you need to be realistic and honest with yourself. Even if you can afford multiple products, are you the type of person who's disciplined enough to follow such a regimen? If you answered "no," you might be a candidate for a protein blend. While not quite as fast as the fastest or as slow as the slowest single-source proteins, protein blends offer most of the desirable qualities of a variety of different proteins in one convenient spot.
Make your selection and stick with it
In order to do something positive for your physique, you need to take your protein(s) continually and consistently at least 60 days. After a couple of months, evaluate and, if necessary, modify your program to add in other proteins, to increase or decrease the amounts used, or to change to a different type of product altogether.