Whey Protein: The Complete Guide

Whey Protein: The Complete Guide

Not all proteins are equal. Some types of proteins, such as whey protein are better than others. Whey protein contains a complete range of essential amino acids, which are absorbed rapidly 1 . It is said to have excellent biological value . Many studies show that this milk protein can help you increase strength, take dry muscle and lose large amounts of body fat 2 .

Whey Protein: The Complete Guide

On the other hand, whey protein is more than just a protein. There are many other nutrients inside this whey, and some have powerful biological effects. For example, whey protein has shown benefits for depression, blood pressure, blood sugar and even help treat symptoms of HIV and cancer 3 .

This is actually one of the most studied food supplements in the world. So here is a complete guide on whey protein, with what it is, how it works and how it can help you achieve your goals: gain muscle and lose fat.

What is Protein Whey?

Whey Protein is a mixture of proteins that are found in whey. Whey is the liquid part of the milk that floats in the cheese. Milk contains two main types of proteins: casein (80%) and whey (20%).

Whey proteins are found in the liquid part of the milk. When the cheese is made, the whey is removed so that the fatty parts of the milk coagulate properly. If you have already opened a yogurt that contains a floating liquid above, this is whey. Manufacturers of cheese were used to discard it before discovering its nutritional value, and especially commercial value.

After being separated during cheese production, whey proteins go through a series of processing steps to become what people generally recognize as whey, a powder added to make protein shakes , meal replacements or Protein bars.

The whey protein does not taste very naturally. This explains why it usually contains aromas: chocolate, vanilla, strawberry are the most popular flavors. Always read the list of ingredients on the packaging labels, as some manufacturers may add additives such as refined sugar.

Taking whey protein is a convenient way to add 25 to 50 grams of protein to your daily intakes. This can be important for bodybuilding practitioners and other athletes but also for people who need to lose weight or have very little protein in their diet.

Most whey proteins can be added as an ingredient to make healthy and delicious recipes, such as wheat pancakes .

Whey protein is generally well tolerated, although people with lactose intolerance can not all consume it. There are also a few people who are allergic to whey.

Whey Protein to Increase Your Protein Intake 

Proteins are the small elementary bricks that make up the human body. They are used to perform various important functions: structural, informative, defenses, etc. This includes tendons, organs, skin … as well as hormones, enzymes, neurotransmitters and all kinds of small molecules. Proteins are also the constitutive components of the contractile elements of the muscle.

Proteins are assemblages of smaller molecules: amino acids. Some amino acids can be produced by the body’s cells, while others need to be obtained from the diet. Those we need to get food are called “essential” amino acids.

The protein sources that provide all essential amino acids are therefore the best … and whey proteins are part of it.

It contains especially many branched amino acids and also contains a large amount of cysteine 6 .

Whey protein appears to be particularly effective in stimulating growth in humans. Breast milk is actually 60% whey, compared to 20% in cow’s milk.

Types of Whey Protein: Concentrate vs Isolate vs Hydrolysate

There are several types of whey protein. The main difference between them is the way they were made.

  • Concentrate : between 70 and 80% of protein. Contains lactose (milk sugar) and fat. It has the best flavor.
  • Whey isolate : 90% protein or more. The whey isolate contains less lactose and fat, but it lacks many beneficial nutrients contained in concentrated whey.
  • Hydrolysate : Also known as hydrolysed whey. This type of whey has been pre-digested so that it is absorbed more quickly. It causes an insulin peak 28 at 43% higher than the isolate 8 .

The concentrated whey seems to be the best in a general way. It is the cheapest and retains most beneficial nutrients found naturally in whey. Many people also prefer its taste, which is probably due to the presence of a little fat.

If you have problems to tolerate concentrated whey, or you are just looking to bring more protein to your diet with a minimum of carbohydrates and fats, whey isolate versions or hydrolyzate, are the best options. Namely, some manufacturers add digestive enzymes to improve the digestion and assimilation of proteins, which is a good thing. On the other hand, some people add sweeteners (aspartame, acesulfame k) that some people tolerate badly. So look at the labels.

Update October 2016: According to a study by several American universities and an Australian university, published in The Journal of the American College of Nutrition on October 6, 2016 9 , hydrolysed whey protein (WPH) would offer an additional advantage by Ratio to concentrated whey: it would increase fat loss. To reach this conclusion, the researchers tested 3 groups taking either concentrated whey, hydrolysed whey or placebo (sugar). After 8 weeks of training, participants taking sugar increased their fat mass by 4.4% while those taking hydrolysed whey lost 6% of their fat mass.

Whey microfiltered vs ion exchange

Whey proteins are extracted by two methods: microfiltration or ion exchange.


Microfiltered whey, also referred to as CFM for Cross Flow Micro Filtration, is a natural method for obtaining high-quality undenatured proteins by filtration through pores on ceramic members at low temperatures. Long and more expensive, the microfiltered whey contains a small amount of naturally occurring fat, lactose, minerals and especially the intact biologically active elements beneficial to health .

Ion Exchange

Ion-exchange treatment involves separation of proteins by their electrical charges. Two chemicals are used to achieve this: hydrochloric acid and sodium hydroxide. The cost of this method is more than half less expensive compared to microfiltration extraction. However, because of the chemicals used, some of the proteins are damaged because of the pH:

  • Immunoglobulins: antibodies or immune system stimulants.
  • Lactoferrin: antibacterial, control of iron transport, stimulation of the immunity, stimulation of the bifidobacteria for the health of the digestive tract.
  • Alpha-lactalbumin: a source of tryptophan which helps to promote the production of serotonin and to lower the level of cortisol.

As you can see, many good things are lost with the production of whey by ion exchange. One of the advantages of this technique is that the finished product contains a little less fat and lactose compared to the microfiltered whey. This is part of the sales arguments heavily used to attract consumers.

Effects of taking whey protein on muscle mass and strength

The most known effect of whey protein, is to help the body increase muscle mass and strength. Whey Protein is popular among most force sports practitioners (bodybuilding, bodybuilding, fitness, CrossFit) as well as other athletes looking to improve their physical performance.

The main effects / benefits of whey protein on muscle are:

  1. Repair and Construction : Provides proteins and amino acids , which serve as building blocks to accelerate muscle recovery and increase muscle growth.
  2. Hormones : it increases the release of anabolic hormones like insulin, which can stimulate muscle growth 10 .
  3. Leucine : It contains a lot of amino acid leucine, which is known to stimulate the synthesis of muscle proteins. 11 12 .
  4. Rapid Absorption : Whey protein is absorbed and used very quickly compared to other types of protein.

Whey protein has been shown to be particularly effective in increasing muscle growth when consumed just before, after or during a workout, but muscle protein synthesis is generally maximized after training 13 14 15 .

 However, a recent study concluded that total protein intake per day is the most important factor for muscle growth. The fact that proteins are consumed around the workout or not seems not to matter much 16 .
  • Compared to other types of proteins, such as soy proteins, whey proteins generally offer slightly better benefits.
  • Compared with casein, the results are more mixed. Whey seems to be effective in the short term, but casein stimulates muscle growth over a longer period. They are therefore not similar, but complementary effects 19 20 21 22 23.
Of course, if your diet is protein deficient, by supplementing with whey protein, it is unlikely to have a huge effect on your results. Whey protein should be a complement and not the basis of your protein sources.

In a study of elderly people who did not eat enough protein, there was no difference in muscle growth with whey protein supplementation with carbohydrates after 12 weeks of training.

Whey protein improves satiety and can help lose weight

It is well known that protein diet can help to lose weight. Indeed, protein is the most interesting macronutrient, by far 25 .

Protein can boost the metabolism by 80 to 100 calories per day, and lower consumption up to 441 calories per day, people who eat a lot 26 27 28 29 .
In one study, protein intake to 25% of total calories to cut the cravings to eat 60%, and reduced the duration of desire to nibble by half 30 .

This appetite suppressant effect was also found in a study conducted by several universities in the United Kingdom. Published in the European Journal of Nutrition in November 2016, 31 the study shows that consuming whey protein after exercise reduces energy consumption at the next meal. This can be useful to support an energy deficit if you are looking to lose weight.

The intake of whey protein is therefore a great way to increase your protein intake in people who are trying to lose fat. Studies have shown that replacing other sources of calories by whey proteins, combined with bodybuilding workouts, can cause weight loss of about 3.5 kg, while increasing the amount of muscle mass.

Because of this, if you are trying to lose weight, taking whey proteins as a supplement can help you both lose weight and keep your precious muscle mass 33 34 .

Other Benefits to the Health of Whey Protein

Whey is not a simple source of high-quality protein, it also contains other beneficial nutrients. It contains lactoferrin, beta-lactoglobulin, alpha-lactalbumin and immunoglobulins.

It lowers blood pressure 36 37 , blood cholesterol 38 , blood sugar 39 and reduces symptoms of stress and depression 40 .

It has also been shown that it can:

  • Help protect against certain cancers 41 42 43 44 .
  • Reducing the symptoms of hepatitis 45 46 47 .
  • Increase bone mineral density 48 .
  • Improving immune function in HIV patients 49 50 .
  • Increase life expectancy in mice 51 .

The fact that whey protein contains a lot of cysteine ​​seems to be a health benefit. Cysteine ​​is the amino acid that increases the amount of glutathione, a very important antioxidant 52 53 .

Dosage and side effects

The recommended doses are 1 to 2 scoops (about 20 to 50 grams per day), usually after the workout. According to a Canadian study conducted at McMaster University in 2009 54 , 20 grams of protein consumed in snack after training is the minimum dose to stimulate muscle protein synthesis.

In fact, the dose depends mostly on the amount of muscle you have 55 . The more muscular you are, the more your body needs protein to maintain its lean mass. There is also the “age” factor that has to be taken into account. According to a study conducted in 2001 at the University of Arkansas for Medical Sciences in the US 56 , older people require more protein to limit muscle loss. In any case, it is recommended to follow the instructions on the packaging.

Despite concerns about taking proteins in addition to kidney damage, a contribution to osteoporosis is not true.

On the contrary, scientists have demonstrated that proteins have a beneficial effect on osteoporosis 58 59 , while having no effect on healthy kidneys 60 61 . However, people with kidney or liver problems should consult a health care professional before taking any.

Eating too much protein whey can cause nausea as well as digestive problems such as flatulence, diarrhea, pain and cramps. Some people are allergic to milk proteins, in this case refer to other sources of protein . But in general, whey protein is a high-quality protein source, which most people can consume without any problem.


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