EAAs vs BCAAs: Which Amino Acid Supplement Is Best for Muscle Growth?

Branched-chain amino acids (BCAAs) are three of the nine essential amino acids: leucine, isoleucine, and valine.

Because the body can’t make these on its own, BCAAs must come from food or supplements.

Essential amino acids (EAAs) include those three plus the other six essentials (lysine, methionine, threonine, phenylalanine, histidine, tryptophan). These are the nine that your body can't make on its own. This is why they're called "essential."

EAAs give a “full set” of building blocks. BCAAs give you three that are key to muscle protein synthesis.

In practical terms, BCAAs can help kickstart muscle-building signals, especially leucine, which acts like a “switch” for muscle protein synthesis.

But without the other EAAs present, your body can’t sustain that process.

BCAA and EAA supplements have been studied for decades, and each have fallen in and out of favor at different times. Why? Trends in the fitness industry often go with the ebb and flow of marketing, not research.

In this article, we'll cut through this and help you choose which is best for your situation, driven by the research.

You can (and do) get all of them from food. Let’s look at the pros and cons of getting these additional amino acids from supplements.

Pros and Cons of BCAA Supplements

Pros of BCAAs:

They can deliver a quick jolt of leucine and the other two aminos. This is great if your goal is just to signal an anabolic state during or around workouts.

They are often cheaper and have less flavor or calories than full protein powders, so some people use them intra-workout or when dieting.

Kaged BCAAs come in an unflavored powder that you can add to other supplements.

BCAAs also do reduce muscle breakdown to a degree. Older studies found BCAA intake lowered whole-body protein breakdown, which can help in a caloric deficit.

Cons of BCAAs:

Because they are only 3 of the 9 essentials, BCAAs alone can’t fully build muscle.

Without the other EAAs, your muscle protein synthesis stalls out.

Studies have found that simply taking BCAAs (even with carbs) does not maximally stimulate muscle growth on its own.

In fact, the researchers said that relying on BCAAs, even combined with carbohydrates, “will not result in maximal stimulation of muscle synthesis.”

BCAA supplements are great to help prevent muscle breakdown, which is helpful for fasting or long workouts, but likely won’t help build muscle.*

Pros and Cons of EAA Supplements

Pros of EAAs:

They fully support muscle growth and recovery. EAAs not only activate the same "anabolic switch" mTOR pathway as leucine, but also give the raw materials to sustain growth.

This can translate to faster recovery and less muscle soreness, especially important if you’re training hard or often.*

EAAs also help prevent muscle loss during cutting or fasting because they supply the body with vital amino acids it might otherwise break down from muscle tissue.

In practice, athletes taking EAAs during or after fasted workouts or intense sessions report feeling more energy and recovering faster.

Cons of EAAs: There are several. And this is why our EAA supplement, Amino Synergy, we’re currently reformulating.

The main drawback is cost. EAAs require more ingredients, so high-quality EAA supplements are usually pricier than BCAAs.

We want Kaged supplements to be both premium and affordable, and that has become more difficult each year.

They also taste a lot stronger. We heard the feedback on Amino Synergy, and are working on reformulating the flavors.

Thrid, if you’re already eating plenty of protein (meats, dairy, or other complete sources) soon after exercise, the extra benefit of EAAs over a normal high-protein meal may be small, or nothing.

In other words, if your diet already gives you all the EAAs you need, an EAA powder may be an unnecessary cost.

How BCAAs and EAAs Compare

Here are some key differences at a glance:

Amino Acid Profile: EAAs include all nine essential amino acids (full spectrum), whereas BCAAs contain only 3 of those (leu, iso, val). All nine EAAs are required to build new muscle, while BCAAs alone can only partly support the processpubmed.ncbi.nlm.nih.gov musclezeus.com.
Muscle Protein Synthesis (MPS): EAA supplements trigger a higher MPS response than BCAA-only supplements. They provide every building block. EAAs are better for muscle growth, plain and simple.
Muscle Preservation: Both supplements can help spare muscle during workouts, but EAAs have a bigger impact. By delivering the full profile, EAAs better prevent muscle breakdown after exercise or during calorie restriction.
Fasting: When taken during fasting, both BCAAs and EAAs produce a modest insulin response, which may negate some of the impacts of fasting. However, EAAs, for the simple fact of there being more amino acids, have a greater insulin response. If your goal is simply to reduce muscle breakdown while fasting, BCAAs may be the choice for you. See more on this in our article on supplements for fasting.
Dietary Context: If your daily diet is already rich in complete proteins (meets daily protein needs), then supplemental EAAs might be redundant. You’re likely getting all the aminos you need from food. In that case, sipping a BCAA drink around workouts may be enough.

But if you have gaps, like if you’re vegetarian/vegan, cutting calories, or training fasted, EAAs can plug those gaps by delivering what your diet might miss.
Cost: On a per-dose basis, BCAA supplements (3-amino powder) are generally cheaper than a full EAA blend. EAAs cost more because they contain nine ingredients.
Adding to Stack: BCAAs, with a less strong flavor and less ingredients overall, is much easier to add to an existing stack. For example, you can add BCAAs to Kaged Hydration and get hydration + muscle support all at once. This is less practical with EAAs, which is why Kaged Amino Synergy is a flavored product designed to take on its own.

Essential amino acid supplements will be better for muscle growth overall, but they come with downsides too. Which one is for you depends on your situation and goals.