Essential Amino Acids (EAAs) vs Whey Protein Powder

UK Fitness Pro
UK Fitness Pro
· 13 min read
EAA and protein supplements

As a long-time lifter and ultra runner, I use whey protein every day and take essential amino acid supplements during workouts. 

Since whey is a complete protein source, it contains all essential and non-essential amino acids (1). Nevertheless, as discussed in my article comparing egg and whey protein, the levels of certain essential amino acids (EAAs; e.g., phenylalanine, tryptophan) are quite low in whey protein. Additionally, while protein supplements provide you with intact protein (i.e., complex molecules comprised of many individual amino acids), EAA supplements provide free-form EAAs (i.e., amino acids not bound up in complex protein molecules), which may facilitate their digestion. Hence, it may be worth taking an EAA supplement in addition to whey protein.

Below, after an overview of the available supplements, we'll take a quick look at the evidence on how protein and EAAs can support muscle building, increase strength, repair muscle tissue, and promote lean mass. 

Protein Supplements

As whey protein is the most widely used protein supplement, the protein-focused studies I've outlined below look at whey protein. However, it's possible to substantially increase protein intake by using powders based on plant protein:

Calories and Macronutrients in 100 Grams of Plant-Based Protein Powders From Myprotein and Bodybuilding Warehouse

BW Pea Protein Isolate3958036
MP Pea Protein Isolate388802.65.5
BW Soy Protein Isolate3689061
MP Soy Protein Isolate360901.81.5
Pure Hemp 504064716.013.0
MP Rice Protein Powder423783.82.1
MP Vegan Protein Blend3667111.02.5
BW Vegan Blend337716.52.5

As discussed in my articles comparing soy and pea protein, hemp and pea protein, rice and pea protein, and hemp and whey protein, there's also lots of evidence that plant-based powders can help you gain muscle, develop strength, and improve your body composition. 

If you'd prefer to stick with a milk-based powder, there are lots of options, all with slightly different macronutrient profiles:

Calories and Macronutrients in 100 Grams of Milk-Based Protein Powders From Myprotein, Grenade, and Bodybuilding Warehouse

 SupplementCaloriesProtein CarbsFats
MP Whey Concentrate405778.37.1
MP Whey Isolate359814.61.1
MP Diet Whey34961134.1
MP Total Protein388814.44.9
MP Casein Powder350824.71.2
Grenade Whey Protein370781.91.8
BW Whey Concentrate375804.75.7
BW Whey Isolate374901.01.0
BW Pure Casein3757813.11.1
BW Casein Hydrolysate3208500

As you can see, most milk-based protein powders use whey protein, though some use casein protein. Check out my article comparing whey and casein proteins to learn about their similarities and differences. For instance, you'll find a graph comparing these proteins in terms of their EAA concentrations. 

If you're not into protein shakes, you could increase your protein intake with protein bars. Here are some of the bars offered by Myprotein:

Calories and Macronutrients in 100 Grams of Milk-Based Protein Bars From Myprotein

Supplement CaloriesProteinCarbs (Sugar)Fats
Layered Protein Bar3543334 (3.2)10
Impact Protein Bar3573132 (3.1)13
Crispy Layered Bar3532737 (3.5)15
Protein Break Bar5261637 (4.2)39
Breakfast Layered Bar4232632 (5.4)21

And here are some of the bars offered by Grenade: 

Calories and Macronutrients in 100 Grams of Milk-Based Protein Bars From Grenade

Supplement CaloriesProteinCarbs (Sugar)Fats
Oreo Protein Bar3893534 (1.7)17
Chocolate Chip Cookie Dough Bar3533434 (2.5)13
Peanut Butter and Jelly Bar3843433 (3.0)17
Fudged Up Protein Bar3873429 (2.8)17
White Chocolate Salted Peanut Bar4033332 (2.5)20

If you'd like to avoid dairy products or animal proteins, check out these plant-based options. 

Calories and Macronutrients in 100 Grams of Plant-Based Protein Bars From Myprotein

Supplement TypeCaloriesProteinCarbs (Sugar)Fats
Vegan Carb Crusher3942731 (3.0)17
Pea-Nut Square4662427 (17)27
Vegan Double Dough Brownie4032142 (8.3)15
Vegan Gooey Filled Cookie3301849 (4.0)11

You might also be interested in my article comparing protein bars and powders

EAA Products

Popular EAA supplements include:

  • Impact EAA (average rating: 4.17/5) – a powder providing all essential amino acids (including lots of leucine), available in two flavours
  • The EAA (average rating; 4.14/5) – a powder providing all essential amino acids (including lots of leucine) and with additional vitamins and minerals, available in four flavours
  • The EAA Sample (average rating; 3/5)– as above, but a small and very inexpensive sample
  • My Vegan EAA (average rating: 4.17/5) – a vegan powder providing all essential amino acids (including lots of leucine), available in a couple of flavours

There's extensive evidence that branched-chain amino acids (BCAAs) can enhance athletic performance. The BCAAs—isoleucine, leucine, and valine—are a subset of EAAs (the remaining EAAs are histidine, lysine, methionine, phenylalanine, threonine, and tryptophan). 

A bag of BCAA powder

My current bag of BCAA powder. You can get an unflavoured version if you want to avoid artificial sweeteners, but I use the tropical-flavoured one as it makes water more appealing. 

Popular BCAA supplements include:

  • Essential BCAA 2:1:1 Powder (average rating: 4.18/5) – a powder providing leucine, isoleucine, and valine in a 2:1:1 ratio, available in various flavours
  • Essential BCAA 4:1:1 Powder (average rating: 4.29/5) – as above, but with a 4:1:1 ratio
  • Vegan BCAA Powder (average rating: 4.36/5) – a vegan powder providing leucine, isoleucine, and valine in a 2:1:1 ratio, available in "unflavoured"
  • Vegan BCAA Sustain Sample (average rating: 4.6/5) – a small and very inexpensive sample providing leucine, isoleucine, and valine in a 2:1:1 ratio, available in various flavours

You might also be interested in my articles comparing EEA supplementation and BCAA supplementation and comparing BCAA in powder form to pills

Muscle Growth

Protein and amino acid supplementation can promote an anabolic response in skeletal muscle and facilitate lean mass growth (2). 

Protein Powder

In one study (3), resistance-trained males received either creatine with carbohydrate (CrCHO), creatine with whey protein (CrWP), whey protein alone (WP), or carbohydrate alone (CHO) and underwent an 11-week resistance training programme. The CrCHO, WP, and CrWP groups experienced significantly greater improvements in skeletal muscle development than the CHO group.

My current bag of whey protein concentrate. I'm not sure I'd get the chocolate brownie flavour again as it has a little less protein than others (69 grams per 100 compared to 80 grams in vanilla, for example), but it tastes amazing in porridge with peanut butter, cinnamon, and seeds. 


In research evaluating the impact of EAA supplements during the early stages of a heavy-load training programme, 29 young males were assigned to either a placebo or an EAA group for 12 weeks (4). 

The 15-gram EAA supplement was composed of 11% histidine, 10% isoleucine, 19% leucine, 15% lysine, 3% methionine, 15% phenylalanine, 15% threonine, and 12% valine. While both groups exhibited notable gains in muscle mass, the enhancements were more significant in the EAA group.

Such effects may be due to EAA supplements contributing to the development of new muscle protein and their role in minimising muscle protein breakdown (5). ​

Muscle Strength

Protein Powder

One study found that recreational bodybuilders consuming 1.5 grams of whey protein per kilogram of body weight daily during a 10-week resistance training regimen saw substantial improvements in strength, as measured by their one-repetition maximum in bench press, squats, and cable pull-down (6).


In another study, twenty-four participants were split into two groups for a three-day workout regimen; one group received a daily dose of 6.6g of EAA mixed with Gatorade, while the other just received Gatorade in a double-blind arrangement (7). Those in the EAA group saw more substantial improvements in strength and enhanced their performance in sprint and run exercises.

Muscle Repair

Protein Powder

Research published in Nutrients (8) demonstrated that consuming whey protein after exercising decreases protein degradation and can enhance maximal strength, the number of repetitions until failure, and peak power 24 hours after physical activity, suggesting that whey protein is beneficial for muscle repair and recovery following intense exercise.

A scoop of whey protein.

Up close and personal with a scoop of chocolate-brownie-flavoured whey protein concentrate. 


In a controlled, double-blind, randomised crossover study (9), ten untrained male participants undertook elbow flexion and extension activities and were administered either a placebo or leucine-enriched essential amino acid (LEAA) supplements thrice daily over a week. There was a significant decrease in serum creatine phosphokinase (CPK) activity, an indicator of muscle damage, in those taking the LEAA supplement, suggesting that it may help reduce muscle damage and aid recovery after exercise.

Body Composition

Protein Powder

One study found that participants gained significant lean muscle mass following a 12-week resistance training programme combined with a daily intake of 19 grams of whey protein isolate (10).


In a double-blind, placebo-controlled experiment (11), older adults were administered either a placebo or a daily dose of 15 grams of EAAs for three months. The findings indicated that EAA supplementation immediately stimulated muscle protein synthesis and resulted in a rise in lean body mass and a sustained increase in muscle protein synthesis over a three-month duration.

Athletic Performance

Protein Powder

One systematic review of 38 research studies assessed the effect of whey protein on enhancing athletic performance when combined with resistance training (12). It found that protein supplementation could significantly promote muscle hypertrophy, strength gains, and aerobic and anaerobic power, contributing to better overall athletic performance. 


A study in Taiwan (13) found that national-level endurance runners achieved 

significantly faster times in a 5,000-meter run

 (average time: 17 minutes, 45 seconds) when they consumed EAAs one hour before running, as opposed to taking a placebo (average time: 18 minutes, 20 seconds). Similarly, their performance improved over 10,000 meters with EAA supplementation (average time: 34 minutes, 52 seconds) compared to when they took a placebo (average time: 36 minutes, 15 seconds). This may reflect EAAs contributing to energy production (5)

Overall Health

EAA supplements, as well as protein supplements that contain EAAs, may have many health benefits in addition to those related to athletic performance: 

  • EAAs play a crucial role in supporting immune function by aiding in the production of antibodies and immune system cells, with studies indicating that supplementation can enhance immune responses (14).
  • Furthermore, amino acids such as tryptophan are precursors to serotonin and melatonin, suggesting that supplementation could improve mood and sleep quality (15).
  • Additionally, amino acid supplements can improve metabolic health by aiding in the regulation of blood sugar levels, thus offering potential benefits for individuals with diabetes or metabolic syndrome (16).
  • Amino acid supplements, particularly those containing glutamine, can promote the health of the digestive system by enhancing the integrity of the gut barrier (17).

EAAs vs Protein Powder: What's the Best Option?

The answer to this depends on your goals and diet, as different amino acids are linked to various outcomes, and each person's diet will have different amounts of certain amino acids. 

However, if I had to choose, I would choose a whey protein powder over an essential amino acid supplement. One reason is that whey protein provides a lot of leucine, and there's extensive evidence linking this EAA to increased muscle protein synthesis (18, 19) and enhanced endurance and power (20). Yes, you could get more leucine from an EAA, but a single scoop of whey protein contains as much leucine as is typically administered to participants in studies in which positive athletic outcomes are observed. A second reason for choosing whey protein is that it contains important non-essential amino acids. 

For instance, serine can increase perceived energy levels during exercise (21), and cysteine can minimise muscle breakdown following workouts (22). 

What's the Best Time to Take EAAs and Protein Powder?

Research featured in The Journal of Sports Medicine and Physical Fitness indicates that consuming EAAs post-exercise is more effective at reducing muscle soreness than taking them beforehand (23).

A study published in the Journal of Exercise Rehabilitation (24) found that the timing of whey protein intake, whether before, after, or both, did not significantly impact muscle recovery or damage indicators. 

However, as amino acid levels in the blood return to baseline within 2–3 hours of consuming protein (25), it's common for people focused on building muscle to consume high-protein meals every few hours. 

How Much is Enough Protein?

According to the Mayo Clinic, those engaged in resistance training or preparing for endurance events should aim for 1.2 to 1.7 grams of protein per kilogram of body weight per day

Therefore, a 70-kg person (about the average weight of a woman in the UK) would aim for 84 to 119 grams, whereas an 85-kg person (about the average weight of a man in the UK) would aim for 102 to 145 grams. Eighty-four grams is about four scoops of whey protein concentrate, while 145 grams is about seven scoops. However, it would be best if you aimed to get a substantial amount of your protein from food sources that contain other nutrients. Lean meats like chicken and turkey are high-quality protein sources, providing over 30 grams of protein per 100 grams of leg or breast meat. 

Plant-based sources of protein recommended by the American Heart Association include beans, seeds, chickpeas, nut butters (e.g., peanut butter, cashew butter, almond butter), peas, tempeh, and tofu. 


Thus, numerous studies indicate that the benefits of EAAs and dietary protein include an increase in anabolic rate, the development of new muscle tissue, and enhanced strength, muscle repair, and body composition. 

Since you're interested in protein powders and other dietary supplements, you might like one of these articles:

About the Author

Dave Robinson, a co-founder of, has a background in psychology (BSc) and neuroscience (MSc, PhD). As well as strength training, he enjoys endurance challenges and has run ultramarathons, cycled across several countries, and completed the Three Peaks Challenge. When writing, he draws on scientific evidence to understand the pros and cons of different diets, supplements, and training regimes. 

The author riding a bike


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Kim, J., Lee, C., & Lee, J. (2017). Effect of timing of whey protein supplement on muscle damage markers after eccentric exercise. Journal of exercise rehabilitation, 13(4), 436–440. 

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