Amino acids are one of the most studied performance enhancers of the last 40 years. Of the many aminos acid supplements available, branched-chain aminos (BCAAs) are the most popular amongst athletes. Some performance athletes swear by their benefits for muscle gain, recovery, and athletic performance.
But BCAAs are not as great for muscle building and performance as you've been lead to believe.
New research has shown BCAAs may actually slow the rate of muscle gain and may even have negative effects on overall health.¹
So, if BCAAs aren’t all they're cracked up to be for performance or building muscle, why all the hype?
And, more importantly, what is the best supplement for performance and building muscle?
This is where Essential Amino Acids (EAAs) come in.
Essential amino acids have all of the benefits of BCAAs—and then some. Scientific literature backs them up as one of the best supplements you can take to enhance your athletic performance, recovery, and overall health.
But First, What Exactly Are Amino Acids?
Amino acids are the building blocks of protein. They act as the catalyst for nearly every chemical process in your body. They support processes like protein synthesis, muscle gain, brain function, hormone regulation, metabolism, and more. There are 20 amino acids in total, and all of them are necessary to make the magic happen for your health and performance.
Okay, so what are EAAs and how can they help my performance?
Essential amino acids are amino acids that your body can’t make on its own—and therefore must be consumed through diet or supplementation.
They are found in protein-rich foods like meat, fish, and eggs, and of course, amino acid supplements.
Each EAA plays a different role in supporting your body. Here are the top nine EAAs and what they do to support your health and performance:
- Leucine, one of the most crucial EAAs for muscle protein synthesis, is essential for building muscle, blood sugar regulation, and producing growth hormones.⁷
- Lysine plays a role in growth hormone secretion, which supports muscle repair and recovery. It’s also an important part of structural proteins like collagen and elastin, which help build strong connective tissue.²
- Methionine helps the body process and eliminate fat, promotes heart health, and supports the liver to eliminate toxins in the body.³
- Phenylalanine has pain-killing and anti-depressant effects and is important for processing norepinephrine and dopamine. It also helps the release of adrenaline and noradrenaline, which are important for a healthy nervous system.⁴
- Threonine promotes a healthy metabolism and immune system. Like Lysine, it’s also an important component of structural proteins and connective tissue.⁵
- Tryptophan is a precursor for serotonin, which manages sleep, appetite, and mood. It also has pain-suppressing qualities and can increase pain tolerance during hard workouts or competitions.⁶
- Isoleucine helps prevent muscles from breaking down during exercise, which may support faster recovery.⁸
- Valine helps stimulate muscle regeneration and is involved in energy production. It’s also important for immune function, hemoglobin production, and energy regulation.⁹
- Histidine is a precursor to histamine, which can help the body respond to free radicals produced during exercise. It’s also a precursor to carnosine, which turns lactic acid back into usable fuel and reduces soreness.¹⁰
Back to BCAAs for a Moment
The popular benefits that many people associate with BCAAs, like muscle growth and performance enhancement are often overstated, misunderstood, and sometimes flat out wrong.
This is because your body needs all 9 EAAs, and BCAAs contain only 3 of the 9. Without having all of the EAAs, your body is left with no choice but to break down muscle in order to find the last six aminos that are missing.
A recent meta-analysis of research conducted between 1985 and 2017 revealed zero human studies in which BCAAs alone were responsible for more efficient protein synthesis or improved athletic performance.¹¹
In fact, the meta-analysis discussed two studies that found that BCAAs actually decreased muscle protein synthesis and instead increased the catabolic rate of lean tissue. This means that muscle was being broken down faster than it was repaired.
In other words, BCAAs don’t work on their own. All 9 EAAs are necessary to complete protein synthesis and muscle growth.
The study concluded that the idea that BCAA supplements alone stimulate muscle growth or produce an anabolic response is entirely untrue. And that’s just the beginning. In addition to being ineffective for building muscle or faster recovery, BCAAs can also have a negative impact on one’s overall health:
High doses of BCAAs without the other 6 amino acids can deplete B vitamins. The use of BCAAs requires several B vitamins in order to work.¹² A B vitamin deficiency can disrupt hundreds of biological functions like digestion, nervous system function, brain health, and hormone production.
An overabundance of BCAAs can hinder serotonin production. The BCAAs and tryptophan both use the same carrier system to get to the brain.¹³ This means too many BCAAs can disrupt the brain’s ability to process tryptophan and can create a shortage of serotonin. Low serotonin is linked to depression, anxiety, sleep problems, carbohydrate cravings, attention disorders, and more.
BCAAs, in isolation, may cause insulin resistance and interfere with blood glucose levels. Increased BCAA levels are linked to a high risk of metabolic disorder and insulin resistance,¹⁴ and may even predict the development of type 2 diabetes.¹⁵
Why EAAs Are Crucial for Building Muscle
Even though BCAAs are still essential for human health and actually serve as a good source of fuel for workouts, they simply don’t build muscle without the help of EAAs.
Here’s how EAAs can support your performance in ways that BCAAs cannot:
- Muscle Maintenance: The amino acid leucine, in particular, has been shown to be crucial in promoting gains in fat-free mass and muscle mass. The full spectrum of EAAs help preserve muscle mass, especially when training in a fasted state. They help decrease muscle damage and promote a healthy inflammatory response.¹⁶
- Exercise Recovery: Supplementing with EAAs after working out increases muscle protein synthesis and helps grow muscle mass. This may support faster recovery and less fatigue after training.¹⁷
- Appetite Regulation: Having the right balance of amino acids may help with appetite and hunger pangs because EAAs activate the brain cells that regulate hunger and feelings of fullness.¹⁸ ¹⁹
- Cognitive Function: Ample tryptophan is necessary to make serotonin in order to promote good sleep and better cognitive performance.²⁰
- Improved Sleep: Amino acid supplementation has been shown to improve sleep and mood.²¹
- Metabolic Health: The proper ratio of amino acids could increase red blood cell count. They can also lower fasting blood glucose levels, support better red blood cell formation, and improve glycogen stores.²²
- Fasting and Ketosis: Consuming too much leucine can trigger an insulin spike, which may “break a fast” and interfere with ketosis.²³ However, this only happens when leucine levels aren’t balanced by the other EAAs, which help buffer the glycemic response.²⁴ The insulin response from supplementing with the right ratios of EAAs won’t interfere with fasting or ketosis, and might even make these processes better!
As you can see, providing your body with the full spectrum of EAAs—rather than just 3 of them from BCAAs—has a myriad of benefits that extend far beyond muscle-building.
Think of it this way: BCAAs start the race, but the other six EAAs finish the race.
Essential amino acids are a true nutritional powerhouse that can help you optimize your training, recovery, sleep, mood, and so much more.
However, finding a quality EAA supplement can prove to be challenging. Many EAA supplements have added sugar, stimulants, artificial ingredients, or extra calories.
But there’s one EAA supplement that has all of the benefits and none of the junk: Kion Aminos.
“Since taking Kion Aminos I notice more energy during my workouts and less soreness after my workouts. I enjoy them so much I have recommended them to others in my gym.”
- Vince M (verified buyer)
Kion Aminos is one of the cleanest, most effective amino acid supplements available. It contains all 9 EAAs and is packed with 40% leucine to maximize muscle protein synthesis.
Build lean muscle with Kion Aminos, your #1 source of all 9 EAAs.Buy Now
* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
© 2022 Kion. All rights reserved.
Is it possible to get a version without stevia etc?
You’ll find the exact same EAA content and ratios here: https://getkion.com/products/aminos-capsules
Thank you Ben, as always the articles that you present are educational.
As an old college biology major who was drafted by the NFL, and currently maintains an active lifestyle, I have always sought out how and why the body works as well or, as poorly as it does. When information and data began being published about EAA’S and BCAA’s I wanted to learn more. Thank you for your informative write up. This kind of material is a “must know” subject matter. What can be done to make it more prevalent?
Bob Hunt on
Very informative article. Eaa’s for me. Thanks
Mark Kirkpatrick on
Jack DeGidio on