Whey protein is one of the most popular and sold types of sports nutrition. It is referred to as “the best protein for gaining muscle mass,” “the fastest,” and “the richest in BCAA amino acids.”
In this article, we will explain why whey protein is considered the best in bodybuilding, introduce scientific studies on its effectiveness for muscle mass gain and weight loss, and clarify the differences between types of whey protein (concentrate, hydrolysate, and isolate).
Main thoughts:
What is whey protein?
Whey protein is derived from cow’s milk. Milk protein consists of two types: casein (80%) and whey protein (20%).
Whey is a not very pleasant-tasting and smelling translucent liquid that is a byproduct of cheese production. It is often found on the surface of sour cream or yogurt after the package is opened.
Whey contains a significant amount of protein, as well as lactose (milk sugar).
Whey protein has a very high biological value: it contains all the essential amino acids for humans and is very well absorbed.
After the whey is separated during cheese making, it undergoes several technological processes before being turned into whey protein powder, which is the basis for sports proteins, gainers, and protein bars.
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Whey protein is a convenient way to add 25-50 g of protein to your diet. This is important for athletes who are building muscle mass and for those who are losing weight, as scientific research demonstrates the effectiveness of protein for weight loss.
It is important to remember that there is no magic in any sports protein: it is simply more convenient to prepare and consume.
You can also ensure the intake of the necessary amount of protein exclusively through natural protein products.
Whey protein is one of the best and most popular types of protein in sports nutrition; it contains all the essential amino acids, is quickly absorbed, and is convenient to prepare.
Composition of Whey Protein
The composition of whey protein (for example, we took Optimum Nutrition Gold Standard 100% Whey Protein, serving scoop 32 g):
- whey protein itself, which consists of several types of globular proteins, whose molecules are folded into spherical structures and dissolve well in water – 24 g;
- a small amount of fat – 1 g;
- a small amount of carbohydrates – 5 g (of which sugars – 4 g);
- cholesterol – 35 mg;
- sodium – 60 mg;
- flavorings, lecithin, food stabilizer xanthan gum, natural sugar substitute stevia;
- caloric content of one serving (32 g) – 130 calories.
The whey protein is a complete protein (it contains all the essential amino acids in optimal proportions for humans) and has a high biological value, meaning it is very well absorbed.
The composition of whey protein from different manufacturers can vary: this concerns not only the amount of protein but also fats, carbohydrates, and sugars. This is indicated by laboratory studies of proteins.
In addition to protein, it also contains biologically active substances that are beneficial for health.
Scientists say that thanks to them, whey protein can be useful for alleviating symptoms of depression, normalizing blood pressure, blood sugar levels, and even for treating cancer and HIV.
Whey protein itself has a unpleasant taste and flavorings are usually added to enhance its taste. The most popular flavors are chocolate, strawberry, vanilla, and banana.
The carbohydrates in whey protein are mainly represented by lactose or “milk sugar”.
It is lactose that gives milk its sweet taste and it is also the reason for lactose intolerance – a digestive disorder that affects about 70% of the world’s population.
The lactose content varies in different types of whey protein (see below): the concentrate has less than milk, while the isolate and hydrolysate have it almost completely removed during processing.
In addition to protein, whey protein contains carbohydrates, fats, cholesterol, sugar substitutes, and flavorings. The composition of whey proteins from different manufacturers can vary significantly.
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Benefits of whey protein. Scientific research
The beneficial properties of whey protein are explained by its unique amino acid composition, rapid absorption rate, content of biologically active substances, and, of course, the fact that it is a source of protein.
Among these beneficial properties are:
- benefits for gaining muscle mass;
- benefits for weight loss;
- benefits for health.
1 Benefits for gaining muscle mass
Scientific studies indicate that whey protein is beneficial for building muscle mass, maintaining it, recovering, and increasing muscle strength 1-6. Of course, this is under the condition of physical activity.
Proteins are the main building blocks in our body.
During the digestion process, the protein molecule is broken down to the level of amino acids, from which muscle proteins are then “assembled” – muscle mass increases.
All proteins consist of amino acids, which are linked together like links in a chain. Some of them the body can produce on its own (non-essential amino acids), while others must constantly be obtained from food (essential amino acids).
Amino acids are used to create organs, tissues, tendons, enzymes, neurotransmitters, hormones, and muscles.
The best protein can be called a protein that contains all essential amino acids in the necessary amounts for humans and is absorbed as fully as possible.
Whey protein is among the best.
And here’s why.
Properties of whey protein that explain its effectiveness for gaining mass:
Building material
It contains all the necessary amino acids, the building blocks required for the synthesis of muscle proteins and anabolic hormones that stimulate even more muscle growth.
Hormones
Whey protein, upon entering the body, increases the production of anabolic hormones that stimulate muscle growth, particularly insulin 17.
BCAA Amino Acids and Leucine
Whey protein is particularly rich in BCAA amino acids (leucine, isoleucine, and valine), which are known for their anabolic function 14. Whey protein consists of 25% BCAA; this is more than in any other natural protein.
The amino acid leucine is often referred to as “the most anabolic amino acid”, highlighting its important role in muscle growth. It stimulates muscle protein synthesis at the molecular and genetic level 18,19.
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Rapid absorption
Whey protein is absorbed very quickly compared to other types of proteins 20.
Fast proteins are most often recommended to be taken immediately BEFORE, AFTER, or DURING training, when it is important to ensure rapid gastric emptying and/or the delivery of amino acids to the muscles.
If taken when the body’s acute need for protein is not present, a rapid influx of amino acids will produce the effect of carbohydrates: they will be used for energy or converted to fat.
That is why taking whey protein at night is a mistake.
The effectiveness of whey protein in stimulating muscle growth is also indirectly evidenced by the fact that the protein in a mother’s breast milk consists of 60% whey protein, while cow’s milk contains 20%.
Comparison of the effectiveness of whey protein with soy and casein in muscle mass gain
Comparative trials of whey protein with other types of proteins show greater effectiveness of whey compared to soy protein and casein: whey is 31% more effective for muscle mass gain than soy and 132% more effective than casein when taken after training 6.
(The experiment used hydrolyzed whey protein).
The authors of the study explain this difference by the faster absorption rate of whey protein and its higher content of the amino acid leucine.
Similar results are demonstrated by other studies 26,27.
A few words about casein.
There is a significant difference in the absorption rate between casein and whey protein: casein is a “slow” protein that is absorbed over several hours, providing a prolonged gradual release of amino acids into the bloodstream. This makes it useful as a source of protein during periods when the body goes without food for an extended time.
That is why casein and products containing it, such as cottage cheese, are recommended to be taken at night.
The combination of whey protein and casein has ideal properties for muscle growth 28-32, as it benefits from the advantages of both types of protein in absorption rate.
One of the principles of proper protein consumption for muscle mass gain is the ability to utilize the properties of “fast” and “slow” proteins.
The benefits of whey protein for muscle mass gain are explained by its complete amino acid profile, especially the high content of BCAA amino acids, rapid absorption, and stimulation of anabolic hormone production.
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2 The Benefits of Whey Protein for Weight Loss
The effectiveness of whey protein for weight loss has been demonstrated in numerous studies on individuals with normal weight, excess weight, and obesity 7,9.
However, it is important to understand that the benefits for weight loss are characteristic of all protein products, not exclusively of whey protein. This is why in all low-carbohydrate diets, which are the most effective for weight loss, the proportion of protein increases.
This can be explained by the fact that:
- protein, compared to carbohydrates and fats, better satiates and suppresses appetite: on a protein diet, a person typically consumes 440 fewer calories per day 34-38;
- protein-rich food increases the internal metabolic rate by 80-100 calories per day; this is important because the internal metabolism is the main consumer of calories in the body, and thus its activation is one of the most important factors for weight loss.
- digesting protein requires approximately 30% more energy than digesting carbohydrates and fats.
In one study, when the protein content in the participants’ diet was 25% of the total caloric intake, it led to a significantly stronger feeling of fullness (60% more) and a reduction in the desire to eat before bedtime (50%) 39 compared to a diet with normal protein levels.
A similar effect is observed with the consumption of other protein products, such as eggs.
According to a meta-analysis of available studies involving over 600 individuals attempting to lose weight, increasing the proportion of whey protein along with strength training allows for an average weight loss of 4 kg while simultaneously maintaining and even increasing muscle mass 40.
In one experiment, whey protein showed the best results compared to egg white, tuna, and turkey in reducing appetite and the number of calories consumed in subsequent meals 10.
Soy protein is significantly less effective for weight loss than whey protein 8,26.
Moreover, numerous facts indicate the health risks associated with soy and soy products, especially relevant with regular consumption.
Whey protein can be beneficial for weight loss as it has appetite-suppressing properties and increases the rate of internal metabolism. However, this is not an exclusive property of whey protein: all protein products have such an effect.
3 Benefits of Whey Protein for Health
Cow’s milk, from which whey protein is derived, is known for its nutritional properties: it is a source of protein, vitamins, and minerals, among which the most well-known is calcium.
But the nutritional properties of milk are not limited to this.
It also contains biologically active substances that provide protection against diseases in mammalian offspring and enhance their ability to fight them – immune function.
It is believed that the consumption of these biologically active substances by adults can boost immunity and offers numerous health benefits 47,48.
That is, the health benefits of whey protein listed below are not inherent to whey protein itself in the understanding of “type of sports nutrition,” but to the biologically active substances contained in it (including some amino acids and specific proteins).
It is evident that the concentration of such substances varies in different types of whey protein and logically decreases with technological processing, proportionally to the degree of this processing.
The health benefits of whey protein include:
- reduction of blood pressure 49,50;
- normalization of blood sugar levels 51;
- antidepressant and anti-stress effects 52;
- reduction of “bad” low-density cholesterol and triglycerides in the blood 50;
- anti-cancer effects 53,54,55,56;
- improvement of liver function in hepatitis 57,58;
- increased bone strength 59;
- strengthening of immune function in HIV carriers 60,61.
Scientific research indicates the benefits of biologically active substances in whey protein for human health (for cardiovascular health, anti-cancer effects, bone strength, immunity). However, their concentration varies significantly in different types of whey proteins.
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Types of Whey Protein
There are several types of whey protein. They differ in protein, lactose, and biologically active substances content.
| Types of Whey Protein | |
|---|---|
| Whey Protein Concentrate | 70-80% protein, some amount of lactose and fat, the most pleasant taste, the highest content of biologically active substances |
| Whey Protein Isolate | 90% protein (or more), less lactose and fat, as well as beneficial biologically active substances than in concentrate |
| Whey Protein Hydrolysate | A form of whey protein in which protein molecules are partially broken down into peptides (chains of amino acids) for even faster absorption |
Whey protein concentrate is probably the best and most popular of all three types, based on the price/quality ratio:
- it is the cheapest of the three;
- it retains the most biologically active natural substances;
- its taste qualities are better.
The more pleasant taste of whey protein concentrate is explained by the presence of some amount of milk sugar (lactose), which gives milk its sweet taste, and fat.
Whey protein isolate is a purer form of this protein: it contains more protein and less lactose.
Isolate is an alternative for those who have increased sensitivity to lactose or need a source of pure protein with low carbohydrates and fats.
Types of whey protein include: concentrate, isolate, and hydrolysate. They differ in relative content of protein, lactose, and fats, as well as the form of protein. The most popular and optimal in terms of price and taste qualities is whey protein concentrate.
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How to Take Whey Protein for Muscle Gain?
The usual recommended dose is 1-2 scoops (approximately 25-50 g) per day, preferably after a workout.
The dose depends on the total amount of protein consumed per day.
If the diet contains enough natural protein foods, then the benefit of taking any types of sports proteins, including whey, is very questionable.
This is confirmed by scientific research. In one study, taking protein on a full protein diet for 12 weeks showed no difference in muscle mass changes 33.
Scientific research indicates the particular effectiveness of whey protein in gaining muscle mass when it is consumed right before, after, or during a workout, but the maximum effect is observed when consumed immediately after a workout 21-24.
At the same time, a meta-analysis of numerous studies on the impact of protein timing on muscle mass gain and strength increase shows that the total amount of protein consumed throughout the day is more important for muscle growth than the specific moment it is ingested: i.e., there is no difference whether protein is taken before, after, or during a workout 25.
Despite the fact that whey protein is most often recommended to be taken before, during, or after a workout, scientific studies show that for muscle growth, the total amount of protein consumed throughout the day is important, rather than the specific timing of intake (before, after, during a workout)
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Note
On many packages of whey protein, as a marketing tactic, manufacturers prominently display “100% Whey”.
This label does not carry any meaningful weight: there is no doubt that in the production of such protein, manufacturers used only whey.
The purpose of such a label is to create a purely psychological effect: we like to pay for something that is 100% what we want to buy.
At the same time, it would be INCORRECT to interpret such a note as an indication of “the best quality protein”.
Is whey protein harmful to health?
Whey protein is considered relatively safe when consumed in recommended doses.
Sometimes its use may be accompanied by digestive disorders such as nausea, bloating, diarrhea, and pain in the digestive organs, which are mainly characteristic of cases where it is consumed in excessive amounts.
For some individuals, dairy types of protein may cause allergies.
Scientific sources do not provide information on serious harm to human health specifically from whey protein; however, it is characterized by the same side effects as other types of protein, primarily of animal origin, in large doses: decreased bone density (risk of osteoporosis), formation of kidney stones, increased cancer risk.
Whey protein is not recommended for those with allergies to dairy products, lactose intolerance, or liver or kidney diseases.
Whey protein is considered safe when consumed in recommended amounts. The harm to health comes from the overall consumption of protein in excessively large doses, primarily of animal origin and its biologically active types.
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Conclusion
Scientific research confirms the reputation of whey protein as one of the best for gaining muscle mass in bodybuilding: it has a high absorption rate and an ideal amino acid profile, and it is indeed very effective for muscle mass gain.
In addition, its consumption can be beneficial for weight loss, and the biologically active substances in its composition offer numerous health benefits.
Among all types of whey protein, whey protein concentrate rightfully enjoys the greatest popularity: it is the cheapest, undergoes the least processing, and therefore retains most of the beneficial properties of milk.
The question of the harm of whey protein is ambiguous.
On one hand, it is beneficial for health, as mentioned, and relatively safe.
On the other hand, it is an animal protein, which, according to large-scale scientific studies on the harm of protein, is one of the main carcinogens and is responsible for other negative side effects, especially when consumed in excessive amounts and with a lack of plant food in the diet.
