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Protein Powder

Written by Ben Carlisle

Last updated on: Sep 18, 2022

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What is the best protein powder? This much asked question is one which is often debated! There are so many different types of protein powders available on the market; whey, egg white, diet whey, pea protein, hemp, soy- the list goes on. Not only is there a wide range of protein sources which make up protein powders, but the market for it is vast with many different brands and manufacturers. If that wasn’t enough they are also served in different flavours: chocolate, vanilla, banana and so on. So, it is understandable why deciding which protein powder is the best one for you can feel slightly overwhelming.

Firstly, it is important to understand what protein powder is and why it is taken. Protein powders are made out of a concentrated form of protein food. Examples of these protein foods are animal or plant foods like eggs, dairy, peas and soy. The three most common forms of protein are protein concentrates, isolates and hydrolysates (1). Most protein powders also come with the added benefit of contain lots of added minerals and vitamins which our bodies need and people with certain health conditions may benefit from taking one particular form of protein over another. For example, pea protein is known for its high levels of iron so this might be a preferred source of protein for those with anaemia or iron deficiency.

Traditionally, protein powders were often viewed as something which only men could take, however this not the case, and in fact many protein powders are produced specifically with women’s health needs in mind. Protein powders can be taken by anyone who is looking to boost their levels of protein and amino acid levels. They are frequently taken by athletes as they are a quick and effective way to help maximise their fitness goals- whether it is to lose weight or gain muscle mass. In addition to this, vegan protein powders help to support a vegan lifestyle as sometimes those living off plant-based foods can struggle to get all of the essential vitamins and amino acids our bodies need (2).

You may wonder how can protein powders help people to gain muscle mass and effectively increase weight and also be used as a source to help people lose weight. Well, this is because protein powder is very versatile. Its ability to make you feel full for a sustained period of time helps those who are trying to lose weight and it is often taken as a substitute meal in the form of a shake (3). Further to this, manufacturer have also made diet protein powders, which have added ingredients in to improve weight loss results. Equally, its ability to help your body build and restore muscles quickly post workout means it is a great tool for bodybuilders. Studies have also shown the consumption of protein as a supplement alongside a healthy diet is a great way to maximise your lean body mass index, whilst also improving upper and lower body strength (4).

As you can see protein powders provide multiple functions and this is why which protein powder is best for you comes down to your current health, ethical views and your fitness goals.

Essential amino acids

You have probably heard of the importance of protein in helping to restore our bodies and improve our physic. But you may not know there are over 10,000 different proteins make us who we are and keep our bodies healthy (5). Amino acids are often referred to as the building blocks of protein and there are 20 plus different amino acids which can be found in foods (6)Of these 20 plus amino acids 9 are considered essential and as our bodies cannot produce them we need to attain them from our daily foods. These nine amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine (6). Recent studies have recently shown even well-balanced diets can lack the required amino acids, which is one of the reasons why protein powder is becoming more popular.

A lot of research into the benefits of BCAA or branch chain amino acids, have been undertaken in particular when thinking about the effectiveness of different protein powders. Branched chain amino acids including leucine, isoleucine and valine, play critical roles in the regulation of energy homeostasis, nutrition metabolism, gut health, immunity and disease in humans and are the most abundant of essential amino acids (7). In addition to this there is much evidence to suggest by consuming a protein powder high in BCAA your recovery time post work out will be reduced.

How can protein powder support muscle mass gain?

When we undergo exercise or training programmes structural damage to our muscle fibres occurs, particularly if the workout programme includes repetition of heavy weights. The body uses protein to build and repair this muscular damage and fuse the broken muscle fibres back together. This process is how the muscles in our bodies increase in strength and size. Factors such as how often you repeat lifting the weights as well as the amount of weight you are lifting will in turn influence how quickly muscle mass is gained (5). Many weightlifters, athletes and fitness fanatics will boost their bodies ability to quickly and efficiently regrow these muscles by taking a protein supplement. It is interesting to note, whilst weight lifting and resistance training alone can improve a body’s muscle mass, cardiovascular exercise is also a great way to boost muscle growth. With this in mind exercises like running and swimming can also be beneficial ways to boost your bodies muscle gain.

 If your goal is to boost your muscle mass you are probably wondering how taking a protein supplement can help and which form of protein supplement is the right one for you. Studies have shown complete protein sources which also contain high levels of BCAA leucine (8) are great choice for those working on their fitness. The BCAA’s also known as Branch Chain Amino Acids are key components of muscle protein synthesis and they include the amino acids Leucine, Isoleucine and Valine (9). With evidence to show those who have taken BCAA supplementation are more resistant against fatigue, while also demonstrating enhanced lipid oxidation during exercise (10). In addition to his, studies have shown BCAA is a useful supplement for muscle recovery (11). Interestingly, research has shown leucine in particular drives protein synthesis and suppresses protein breakdown.

This leads us into thinking about which protein powders contain the highest levels of BCAA. Whey protein has particularly high-quality levels of protein and amino acids (12). In addition to this most studies tend to agree whey protein is able to stimulate muscle protein synthesis to a greater degree than other proteins, including casein and soy (13). However, if you are looking for a vegan alternative which supports muscle growth pea protein comes a very close second to whey protein, whilst having the added bonus of being animal free (14).

Losing weight

With so many protein powder supplements on the market, you may wonder which one is best to support weight loss. Generally, the answer to this is dependent upon whether you are an athlete who is on a training programme or whether you are seeking to lose weight on a calorie deficit diet.

For those aiming to lose weight following a calorie deficit diet, Diet protein powders are the best choice for you and they typically come with the main protein source as whey with a vegan blend alternative also readily available. So how can taking a protein powder supplement help with weight loss? Well research has shown high protein diets increase energy expenditure, whilst also helping to control appetite and improve feelings of satiety (15).

What’s different about diet protein powders compared to normal ones? They include added ingredient; which research has suggested could aid the body with burring fat and boost its metabolic rate. These ingredients include CLA (Conjugated linoleic acid), acetyl l-carnitine and Green Tea. Once again, these ingredients are seen in both animal- based and vegan diet proteins.

The most popular diet proteins include: Diet whey protein which has a protein content of about 70% and is made from a mixture of whey protein concentrate (milk) and whey protein isolate. Secondly there is Whey protein blend which is one of the cheaper alternatives or diet powders. Next is 80% diet protein, which as the name suggests has a protein content of 80%. Finally, there is vegan diet protein blend. Typically, these protein blends get their high protein levels by using split peas or soy beans and still contain the same weight loss promoting ingredients which the whey diet proteins offer.

So lets look at these fat-loss promoting ingredients in more detail. L-Carnitine is a low-molecular-weight compound obtained from the same diet as the essential amino acids’ lysine and methionine (16). Studies have shown L-Carnitine improves metabolism and helps to transports fatty acids into your cell’s mitochondria (17).

Green tea extract is included in a concentrated form in the diet protein powders, which means it contains high levels of catechins and moderate levels of caffeine. Research has shown consuming green tea can increase your bodies expenditure of energy over a 24-hour period, making it a suitable component to aid with weight loss (18).

The final ingredient which is often added is CLA. So far only animal studies into the ability of CLA to reduced body fat mass have been undertaken. However, these studies have shown it is an effective substance to improve fat loss. Whilst studies into the ability of CLA to reduce human body fat mass need further research, many scientists do believe CLA is likely has the same effect (19). There are studies to show obese patients who took a CLA supplement over a 12-week period did have a quicker weight loss (20).

Whey protein

Now we’ve looked closely at the added ingredients of diet protein let’s have a think about arguably the most come type of protein powder- Whey protein.

Whey protein power is a highly popular protein powder, which provides high quantities of protein per serving and all nine of the essential amino acids (1). It is made out of the milky by product of cheese, which makes it unsuitable for vegans (21). This milky by product is called whey, hence the name of the protein powder. Whey protein isolates have been identified in studies as the purest protein source available, with it containing protein concentrations of 90% or higher (12).

Whey protein powder is quickly absorbed by the body making it a great choice for those working on their fitness. It is also suitable to aid an arrange for fitness goals, including weight loss, training endurance and muscle gain. It is a complete protein which contains high levels of BCAA leucine (8). For those looking to bulk up or improve lean muscle mass studies have shown whey protein powder is able to stimulate muscle protein synthesis to a greater degree than proteins such as casein and soy (22).  In addition to this for those seeking to lower their weight whey protein powder has properties which have a positive effect on the body’s feelings of satiety and fullness (23). Making it a suitable supplement for those on calorie restrictive diets.

Pea protein powder

Pea protein is a great alternative for those looking for a vegan and hypoallergenic protein powder, due to the fact it is free from the 8 main types of allergens (24). Pea protein is made mostly from yellow split peas, which is what gives the powder its beige tone.  During the manufacturing process, the split peas are firstly left to dry out. Next, they are ground into a powder before finally being added to water- which removes the starch and helps increase their digestibility.

Similarly to whey protein, pea protein powder is suitable to be taken in support of a range of fitness aims. There is much research to show pea protein is a good source of the BCAA and in the case of some brands it is equal to the levels shown in whey protein powders making it a good supplement to help aid the building of muscle, strength and body composition (25, 26).

In addition to this, its high level of protein together with its fibre and resistant starch components, can help to suppress one’s appetite and glycemia (21), which gives the body the sensation of being full for a sustained period and so aid with weight loss goals. When thinking about pea protein in comparison to other protein powders one study suggests pea protein hydrolysate was more effective at increasing feelings of fullness and the desire, than its animal-based rivals milk protein and whey protein (18).

Best time to take protein powder post or pre-workout?

Once you have decided which form of protein powder and which brand best meets your fitness goals you will need to decide when to take your protein supplement.

Some choose to take a protein supplement pre-workout. Typically, this will be around 30 mins before your workout commences but it can also be taken while you work out too. Common ingredients found in pre-workout protein powders are beta-Alanine, Caffeine and Creatine (9), so let’s look into each of these ingredients and how they support our bodies during a workout.

Beta-Alanine has been shown to be able to improve exercise performance in those undertaking High intensity interval training (HITT) and short sprints (9). In addition to this beta-alanine supplementation has been shown to delay the onset of neuromuscular fatigue (27). So to summarise, if you’re taking a protein supplement which contains Beta-alanine it is most beneficial to take before workout, as studies imply it will support your bodies endurance in your upcoming workout.

Caffeine is another ingredient which is often used in pre-workout powders, as it is able to boost athletic performance in both short-term high intensity exercise and endurance-based activities (9). A final ingredient which is often used is creatine; creatine is a naturally occurring compound which is found in skeletal muscle and is made from amino acids which are found in red meat and seafood (9). Creatine is widely used in protein powders and is believed to increase athletic performance, particularly for those who are weight training (9). In addition to this research has shown creatine supplementation can enhance post-exercise recovery and also help with injury prevention during workout (28).

What about Post workout supplements? Post workout supplements tend to include carbohydrates as following workout our bodies need sufficient carbohydrate and protein levels to help with muscle recovery.  Whilst, the carbohydrates and protein you consume in your everyday diet should be enough for moderate intensity exercise such as jogging, swimming or cycling more intense workouts can require a post workout supplementation such as a protein shake or smoothie (9).

But which is better you ask? Pre or post workout supplementation? In truth there is very little evidence to suggest either one has a better effect. There has been much research done into the anabolic window, which is the theory of an optimal time to take training-related protein powders or supplements, but as of yet there is no conclusive evidence to support the time limitations of this window.

Much research has been taken into certifying which has more impact: pre or post workout supplements, but in truth it comes down to personal preference, tolerance, and lifestyle/scheduling constraints (29). Studies have shown, when looking at the wide range of possibilities about when to ingest protein supplements there were no meaningful results consistently attributable to pre- versus post-exercise ingestion (30). Supporting the notion previously stated the trainee should be free to decide when to take their supplements based on what suits them best.

Serving size

You may wonder what the recommended intake for protein is and also what a protein powder serving includes.

The recommended levels of daily protein intake for a healthy adult is currently 0.8 grams of protein for every kilogram of body weight which translates to about 7 grams of protein every day for every 20 pounds of body weight (5).

Looking at what’s within the actual scoops serving itself, will vary greatly between manufacturer, brand and protein source but here are some examples of what you can find protein wise in different protein sources. Per 30g serving: pea protein has around 24g of protein compared to hemp which has around 15g. In soy protein powders there are around 23 grams protein, with whey coming out as the highest levels of 25 grams.

What makes up the remaining grams in these servings? Well this is where you have to do your research and check the label carefully to see exactly what your powder includes. Most powders will also include, added vitamins and minerals, carbs, fat and sugar. Look carefully at the breakdown of sugar. Ideally you want a powder which has less than a gram sugar and aim to have natural flavourings such as powdered fruits and herbs. The reason for this is sugar alcohols, like Xylitol or Erythritol, can cause stomach upset, even in those who do not usually suffer (31).


To summarise, when selecting your preferred protein powder its always important to read the label carefully to see what the other added ingredients are and the benefits they can offer you. Ingredients such as CLA, l-carnitine and Green Tea have been added to diet protein powders as there is evidence to indicate they can support weight loss goals.

The added ingredients can also be an indication of the best time for you to take your supplement- pre or post workout, for example beta-Alanine could be taken before workout as it can support your endurance.

Sometimes added ingredients can be hinderance and it is important to select a protein powder with a low sugar content and preferable one that doesn’t use sugar alcohols.

There is no definitive answer for which protein powder is the best for you, what the best flavour is or when’s the best time to take your supplement. It all comes down to personal choice, preferences and your fitness goals.


1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3905294/    

2. https://pubmed.ncbi.nlm.nih.gov/30167963/  

3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4744604/ 

4. https://pubmed.ncbi.nlm.nih.gov/26403469/

5. https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/protein/

6. https://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/protein/

7. https://pubmed.ncbi.nlm.nih.gov/29570613/

8. https://pubmed.ncbi.nlm.nih.gov/28642676/  

9. https://www.hsph.harvard.edu/nutritionsource/workout-supplements/

10. https://pubmed.ncbi.nlm.nih.gov/21297567/

11. https://pubmed.ncbi.nlm.nih.gov/18974721/

12. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3905294/

13. https://pubmed.ncbi.nlm.nih.gov/25757896/

14. https://pubmed.ncbi.nlm.nih.gov/25628520/

15. https://pubmed.ncbi.nlm.nih.gov/28415067/

16. https://pubmed.ncbi.nlm.nih.gov/12751049/

17. https://pubmed.ncbi.nlm.nih.gov/18646596/

18. https://pubmed.ncbi.nlm.nih.gov/18345020/

19. https://pubmed.ncbi.nlm.nih.gov/11110851/

20. https://pubmed.ncbi.nlm.nih.gov/22261578/

21. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4744604/  

22. https://pubmed.ncbi.nlm.nih.gov/25757896/

23. https://pubmed.ncbi.nlm.nih.gov/24801369/

24. https://pubmed.ncbi.nlm.nih.gov/23229594/

25. https://pubmed.ncbi.nlm.nih.gov/25628520/

26. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6358922/

27. https://pubmed.ncbi.nlm.nih.gov/20479615/

28. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5469049/

29. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3577439/

30. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5214805/

31. https://pubmed.ncbi.nlm.nih.gov/16988647/

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