Branched-chain amino acids, or BCAAs for short, are the three essential amino acids leucine, isoleucine, and valine. You find them in various amounts in all the protein you eat, and you can also get them as BCAA supplements.
BCAAs are marketed to build muscle, reduce muscle breakdown, and improve exercise performance.
In this article, you’ll learn everything you need to know about BCAAs: what they are, how they work, and whether they are worth your money.
- BCAAs stimulate muscle protein synthesis but not nearly as effectively as whey protein.
- There is no evidence that BCAAs help you build muscle mass.
- BCAAs reduce muscle soreness and maintain your energy levels during high-intensity workouts.
Amino Acids 101
Amino acids are the tiny building blocks of proteins in food and the protein that makes up your muscles.
The amino acids connect together and form little chains.
When you eat or drink protein, your body uses amino acids to repair and build cells, including muscle tissue.
When your body digests the protein, it breaks the chains into free amino acids. After passing the intestine walls into your bloodstream, they are ready to go on new adventures to wherever your body needs to fix old, broken-down cells or construct new ones.
If you lift weights, your body incorporates more amino acids into your muscle proteins, increasing your lean muscle mass.
The food you eat provides 20 amino acids in total. They are two different types of amino acids: essential and non-essential.
Your body needs all 20 amino acids to function, but it can make the non-essential on its own. You must provide the essential ones.
Essential Amino Acids (EAAs)
There are nine essential amino acids. They all have complicated names, but you don’t have to memorize them. Your muscles know which ones they need to grow.
In addition to the nine above, the amino acid arginine is essential for children. As an adult, however, your body can make arginine when needed.
A protein containing sufficient amounts of all EAAs is called a complete protein. All animal products provide complete proteins, but plant proteins have too little of one or more amino acids, with a few exceptions, like soy protein.
Non-Essential Amino Acids (NEAAs)
The eleven non-essential amino acids are as follows, in alphabetical order:
- Aspartic acid
- Glutamic acid
Even though your body can make them as needed, you also find them in the foods you eat, often in abundant amounts. In other words, you can be doubly sure you get enough NEAAs, and you don’t have to worry about them for building muscle.
Branched-Chain Amino Acids (BCAAs)
Now we get to the three amino acids you’ve heard so much about and see in supplement stores: branched-chain amino acids, or BCAAs for short.
So what’s unique about BCAAs?
First and foremost, many people believe BCAAs are a separate group of amino acids and often ask what’s the difference between EAAs and BCAAs.
That’s not the case. BCAAs are EAAs.
Sounds confusing? Don’t worry; it’s more simple than it sounds.
Looking at the list of essential amino acids above, you might notice three particular ones: leucine, isoleucine, and valine. Those are the BCAAs. In other words, they also belong to the family of essential amino acids.
The “branched-chain” part simply refers to the chemical structure of BCAAs, which is different from the others. It looks like the branches of a little tree:
That’s the main difference between BCAAs and the other six EAAs. But they are all essential.
You get branched-chain amino acids from all protein-rich food sources but in varying amounts. Animal proteins like eggs and meat contain significantly more BCAAs than plant-based sources. Whey protein powder and other dairy products are especially rich in BCAAs.
Another unique thing about BCAAs is that, unlike the other amino acids, they are not broken down in the liver.1 Instead, they can be used for energy production by your muscles, making them beneficial to fuel high-intensity workouts.
You can also get amino acids as supplements containing all essential amino acids or just the three BCAAs. The BCAA supplement industry is huge and growing yearly, with the global market size exceeding $256 million in 2022 and projected to continue growing.
Building Muscle with Protein and Amino Acids
Soon after you eat a protein-rich meal or drink a protein shake, amino acids appear in your bloodstream. If you use amino acid supplements, they reach your blood even faster because your body doesn’t have to break the chains of amino acids down.
When you flood your bloodstream with amino acids, you flip a switch that tells your body to start building muscle. The process of creating new muscle protein is called muscle protein synthesis.
Not all amino acids trigger muscle protein synthesis. It’s the BCAAs, leucine in particular, that flip the switch.2 3
Once you have high levels of leucine in your blood, a cascade of reactions happens in your muscles, and signals tell them to start creating new muscle protein. Between 2.5–3 grams of leucine per serving maximizes muscle protein synthesis.4 That translates into around 30 grams of high-quality protein like eggs, chicken, or red meat. Whey protein provides so much leucine that 20 grams give you enough.5
If you eat even more protein in one sitting, nothing bad happens, but you won’t build any additional muscle.6
You can also get that amount of leucine from plant-based foods, but you’d have to increase your serving size a bit. For example, you’d need 38 grams of pea protein or 40 grams of soy protein to get the same amount of leucine you get from 25 grams of whey.7
If we’re talking whole foods, you could, theoretically, get enough protein from potatoes alone, but you’d likely get sick of them before long.
Amount of the selected whole-food protein sources to be consumed to allow ingestion of 20 g protein.
BCAA Supplements: Do They Help You Build Muscle?
Now you know what BCAAs are and the basics of how they work. Because they are essential for the human body and play an important role in muscle growth, you might wonder how many grams of branched-chain aminos you should take to get jacked and what the best BCAA supplement is.
To kick-start muscle protein synthesis, you need a certain amount of BCAAs, particularly leucine. However, you could save money and use 0 grams of BCAAs as a supplement, getting it all from food. Doing so would likely be more effective for muscle growth.
But how come? Aren’t branched-chain amino acids the same whether they come from an egg, a whey protein shake, or through BCAA supplementation?
Yes and no. On a molecular basis, yes, but it makes a difference whether you get your branched-chain aminos together with the other essential amino acids, like when you eat that egg or chug that shake, or as a supplement with just the BCAAs.
Short-Term Muscle-Building Effects of BCAAs
Taking branched-chain amino acids alone, like in a BCAA supplement, is not enough. You send the signals for muscle protein synthesis, but nothing much happens if you don’t provide the other essential amino acids simultaneously.
It’s like telling the minifig construction worker to build a wall of bricks, and he does his best to comply, but without the building material (i.e., the other six EAAs), his labors won’t amount to much.
BCAAs on an empty stomach stimulate muscle protein synthesis but not nearly as much as the same amount of leucine from, say, whey protein.
In studies that compare whey protein with BCAAs, whey produces a massive increase in muscle protein synthesis. The BCAA group only gets a 20% greater effect than a placebo or drinking a glass of water.
The bottom line:
Branched-chain amino acids trigger muscle protein synthesis, but regular protein like whey is doubly effective.
Long-Term Muscle-Building Effects of BCAAs
Unfortunately, most studies only look at a short time window when comparing BCAAs with other protein sources. Measuring muscle protein synthesis over a few hours is interesting, but it does not necessarily predict muscle growth.8
The long-term muscle building effects of protein supplementation are well-documented. A 2017 meta-analysis gathered data from 49 studies lasting up to a year, with close to 2,000 participants.9 The researchers found that trained lifters gained, on average, 750 grams of fat-free mass compared to a placebo by adding a protein shake per day.
Adding the same amount of protein from regular foods and a healthy diet would likely produce the same results. The point is that adding protein to your diet equals greater increases in muscle mass when combined with strength training unless you’re already eating a high-protein diet (>1.6 grams per kg or >0.7 grams per pound of body weight.)
However, there is limited research on branched-chain amino acids and long-term results. There is no evidence in the scientific literature for any benefits of using BCAAs to boost muscle growth.
The supplement manufacturers would have you thinking otherwise, though. They often claim that BCAAs will help you gain lean body mass, increase muscle strength, and improve athletic performance.
The problem is that they base those claims on the results of studies lasting a couple of hours. Besides, BCAAs underperform compared to regular proteins in short-term studies even though the ads leave out those numbers.
Recent research finds little or no benefit in using BCAAs for building muscle. A 2021 study gave 30 women who engaged in strength training thrice per week either nine grams of BCAAs per day or a placebo.10
After eight weeks, both groups had gained significant amounts of strength and muscle mass, but it was all from the training. The BCAAs produced no additional effect.
Several scientific reviews look at all the available research on BCAAs and come to similar conclusions.
- A 2017 review states that “dietary BCAA supplements alone do not promote muscle anabolism.” 11 The researchers suggest supplementing with branched-chain amino acids might even decrease muscle protein synthesis.
- The most recent review from 2021 concludes that “BCAA supplementation lacks efficacy for promoting muscle hypertrophy” and that BCAAs are a “clear and seemingly unnecessary monetary cost.” 12
The only piece of research showing actual muscular hypertrophy from BCAA supplementation is a study presented at a conference in 2009 and financed by a manufacturer of dietary supplements.13
It suggested that branched-chain amino acid supplements are superior to whey protein. Men who used BCAAs gained 4 lbs. more lean mass than those drinking protein shakes. Four lbs. in eight weeks!
Muscle gains of that caliber in two months are comparable to results from studies where the participants receive high-dose testosterone injections.
This study was never published and is still only available in the form of the original poster presentation. That makes it inadmissible as scientific evidence, but that fact has not prevented BCAA manufacturers from using it extensively in marketing.
The bottom line:
Research does not support using BCAA supplements to build muscle. They are a waste of money for boosting your strength or muscle gains.
Combining BCAAs and Protein
So, taking BCAAs alone is not very useful for muscle protein synthesis and building muscle.
But what if you add a serving of BCAAs to regular protein? For example, you might eat something that doesn’t give you enough and want to boost the protein content by taking some BCAAs.
First, if your meal already provides 20 or more grams of protein, adding more leucine does nothing.14 Your muscles already have access to all the BCAAs they need to trigger muscle protein synthesis maximally from the food.
If you eat something that does not contain enough protein, you can make that meal more anabolic by adding leucine, but not a supplement containing all three BCAAs.15 16
It might sound strange because leucine plays a significant role in BCAA supplements, but taking all three amino acids at the same time likely causes competition between them during absorption from the gut.
Adding leucine alone to a small serving of protein makes it the equivalent of a much larger portion. However, the effect on muscle protein is very short-lived. You can only maintain the muscle-building effect for several hours by eating more protein. With the leucine trick, your muscle protein synthesis is soon back to fasting levels after that initial peak.
The bottom line:
- Adding BCAAs to a protein-rich meal does nothing.
- Adding BCAAs to a meal with only a little protein also does nothing.
- Adding more proteins to the plate or using another scoop of protein powder is better than compensating with BCAAs.
BCAAs and Muscle Breakdown
Muscle protein synthesis is only half of the hypertrophy equation. The other part is muscle breakdown.
Both muscle protein synthesis and breakdown co-occur 24/7. What determines muscle growth is the balance between synthesis and breakdown.
The dotted line is your muscle protein synthesis, and the green line is your muscle protein breakdown. Muscle protein synthesis increases, and muscle breakdown decreases when you eat a protein-rich meal. Between meals, the opposite happens. Add strength training to the equation, and the peaks grow slightly, leading to muscle growth over time.
When you build more muscle that you break down, your muscles grow bigger. Easy mathematics, right?
Again, looking at an hour or two is irrelevant. The balance between muscle protein synthesis and breakdown over time is the big picture determining if you gain muscle long term.
Regardless, there is no evidence that BCAAs reduce muscle breakdown in any meaningful way.
Many believe protein reduces muscle protein breakdown, but that’s not the case.17 It is insulin that reduces muscle breakdown.18
In other words, carbs and protein indirectly reduce muscle breakdown because they tell your pancreas to release insulin, but not directly.
In addition, you only need moderately elevated insulin levels to reduce muscle breakdown maximally.19 The insulin secretion you get from 20–25 grams of protein is enough. Larger protein servings or adding carbs for greater insulin release does not reduce muscle breakdown further.
After eating or drinking BCAAs or leucine, your insulin levels increase.20 If you take leucine on its own or as a BCAA supplement, your insulin levels only rise a little, but if you combine it with sugars, you create a real insulin spike.21 That means that BCAAs reduce muscle breakdown at rest, but only because they trigger an insulin release.
Do BCAAs Reduce Muscle Breakdown After a Workout?
You have likely seen claims from the manufacturers that consumption of BCAAs not only stimulate muscle protein synthesis but also protect you from muscle breakdown after your intense workouts.
Unfortunately, no study has demonstrated reduced muscle breakdown after exercise by taking BCAAs.22
However, there is some evidence that >200 mg of BCAAs per kilogram of body weight prior to exercise is somewhat effective for reducing indirect markers of muscle damage from exercise.23 That evidence is of low quality, though, with the only high-quality study having a mere six participants.
All manufacturer claims are based on studies where you measure whole-body protein breakdown and include everything made up of protein in your entire body. That means your muscles but also organs like the liver, intestines, skin, and so on. They do not measure muscle protein breakdown specifically and cannot say anything about how or even if BCAAs affect it.
Is Reduced Muscle Breakdown After Training a Good Thing?
Bodybuilders are notoriously afraid of being in a catabolic state, but worrying about muscle breakdown after a workout might be unnecessary. It may not even be a good thing to try to reduce muscle breakdown as much as possible after a gym session.
It would be if reduced breakdown meant protecting undamaged muscle fibers. However, we don’t know if that is the case.
Current research suggests muscle protein breakdown after lifting weights is essential to building muscle. It gets rid of damaged proteins and primes your muscles for growth.
Experts in the field speculate that trying to actively reduce muscle breakdown after a workout as much as possible through nutrition or supplementation might even impair long-term muscle growth. Doing so could be a mistake for anyone trying to gain lean mass.24 25 26
A 2018 review concluded with “caution against strategies that focus on suppressing MPB (muscle protein breakdown) as we contend that efficient removal of damaged proteins would require a robust and fully functional proteolytic response. We are unaware of any potential improvements with respect to skeletal muscle hypertrophy by strategies that suppress MPB.” 27
In other words: there are no known benefits to reducing muscle breakdown after working out, and it might even be a bad idea.
So what should you do instead?
Easy! Pay your dues in the gym, then go for stimulating muscle protein synthesis. Give your muscles what they need after a grueling workout – protein – and you’re good to go.
Eating a protein-rich meal or drinking a shake providing 30 or more grams of protein reasonably close to your training session will maximize your muscle protein synthesis as much as your genetics allow for several hours.
And as demonstrated above, BCCAs are not a good choice for muscle protein synthesis or the best results.
Do BCAAs Help a Weight-Loss Diet?
When you reduce your caloric intake, like when you’re dieting to lose body fat, muscle protein synthesis decreases, and muscle breakdown increases.28 29
That’s not a good recipe for maintaining muscle mass during weight loss.
Even though it might not be a good idea to minimize muscle breakdown immediately following a workout, what about reducing the 24/7 increase in muscle breakdown at rest when you’re dieting?
Supplementing with BCAAs during periods of energy restriction, like during the cutting phase of a bodybuilding diet, might sound like a great idea to minimize or eliminate the potential loss of muscle mass. But is it?
Unfortunately, there is only a little research on the subject, but the few studies looking at BCAA supplementation during calorie restriction do not support it.
In a 2016 study, 17 young and trained men received either BCAAs or a placebo in the form of carbohydrates during eight weeks of strength training while eating fewer calories than they burned.30
The authors of this study, financed by a manufacturer of BCAAs, concluded that BCAAs minimize the loss of lean mass and performance while losing body fat during periods of calorie restriction. They also claimed that the BCAA group lost significant amounts of body fat while the carbohydrate group did not.
Looking more closely at the study result, it shows that the carbohydrate group lost an average of 1.4 kilograms of body fat. In comparison, the BCAA group lost only 0.6 kilograms of body fat. In other words, the opposite of what the researchers concluded.
The BCAA group participants lost less lean mass than the carbohydrate group. However, given the differences in fat loss, that sounds more like the result of losing almost no body fat. The loss of fat-free mass reported in the carbohydrate group could be the result of a faster weight loss, not the lack of BCAA powder.
Other scientists also pointed this out in a review article the year following the publication of the original study.31
The participants in the BCAA group reduced their resting energy expenditure by an average of 400 kcal per day. The carbohydrate group did not. This astounding and unexplainable drop in resting metabolic rate only adds to this study’s uncertainties.
In a more recent 2021 study, 132 adults on a weight-loss diet were assigned to one of three groups for 16 weeks:
- One ate a standard-protein diet + a placebo supplement.
- The second ate the same standard-protein diet + 0.1 grams of BCAAs per kilogram of body weight. For example, someone weighing 75 kilograms (165 lbs.) would have supplemented their diet with 7.5 grams of BCAAs.
- The third group ate a high-protein diet with a similar calorie deficit but without added BCAA.
After 16 weeks, all three groups had lost similar amounts of weight and body fat. Supplementing with BCAAs did nothing to preserve muscle mass for the second group. However, those who simply upped their protein intake lost significantly less lean mass than the BCAA group.32
In other words: eating more protein is a more effective way to prevent muscle loss during a diet than using BCAAs.
>> The 5 Best Supplements to Get Shredded
Other Uses for BCAA Supplements
So far, we’ve talked much about body composition, and BCAAs fall short in every scenario compared to regular protein.
However, amino acids have more uses than building muscles, from drug administration for medical conditions to mental focus and immune function. Let’s take a closer look at the case for BCAAs outside of muscle growth.
BCAAs and Muscle Soreness
Everyone who’s worked out vigorously after a layoff or tried a new exercise and gone all-out knows the feeling the next day. Your muscles get so sore that walking down the stairs becomes an ordeal.
After a century of research, we still don’t know what delayed onset muscle soreness, or DOMS, really is. There are several theories, though. The most prevalent is that the pain originates from microscopic injuries to the muscle fibers.
Numerous recent studies show that branched-chain amino acids reduce DOMS, as shown in two meta-analyses that gather data from all individual studies. They conclude that BCAA supplements significantly reduce muscle soreness after exercise.33 34
How BCAAs reduce DOMS is unknown, but researchers speculate that leucine might enhance muscle recovery and lessen painful sensations. Other theories include reduced damage to the cell membranes of your muscle fibers and decreased muscle inflammation after working out.
Regardless of the mechanisms, the research is straightforward: “large decrease in DOMS occurs following BCAA supplementation after exercise compared to a placebo supplement.” Say what you will about BCAAs for building muscle, but it’s one of the best supplements for reducing soreness.
However, no studies have compared branched-chain amino acids to regular protein, only to placebo supplements or carbs. Could a whey protein shake providing the same amount of BCAAs be as effective? Quite possibly, but it remains to be seen.
BCAAs and Muscle Recovery After Training
Even if you’re not a high-level athlete, recovering quickly from a strenuous training session means improved workout performance and long-term gains.
Several studies examine if BCAAs improve muscle recovery time.
A 2019 study randomized 24 young, untrained adults into a BCAA group and a placebo group.35 The first group received 8 grams of BCAAs + 4 grams of maltodextrin, and the second 12 grams of maltodextrin.
On the first and third days of the study, they performed leg workouts involving leg presses and hack squats.
The scientists assessed how well the participants recovered from the training 30 minutes, 24 hours, and 48 hours following the first workout. They looked at the number of repetitions the subjects could do, their perceived exertion in the last training session, and their jumping ability.
The number of repetitions the subjects could perform remained unchanged. Still, they all got sore, their rating of perceived exertion increased, and their jumping ability declined—all expected effects of a strenuous or unaccustomed training session.
However, there were no differences between the groups. The participants’ performance declined at the same rate, and the ones who ingested BCAAs were no better off than the ones who got a placebo in the form of carbs.
That study looked at untrained people, but what about those with strength-training experience?
A 2018 study gave 20 resistance-trained men either a commercial BCAA supplement or a taste- and color-matched carbohydrate placebo before and after a grueling leg training session.36
The leg workout consisted of ten sets of eccentric squats and five sets of 20 body-weight split jumps. If that doesn’t make you sore, nothing will.
The researchers measured performance in the vertical jump, maximal isometric contraction, jump squats, and markers of muscle damage.
They found that branched-chain amino acids reduced muscle soreness compared to the placebo. In addition, those who got the actual supplement recovered their isometric muscle function (isometric exercise is when you flex your muscle against something that doesn’t move, unlike regular strength training) faster.
BCAAs did nothing for any other measures of muscle function.
The bottom line:
If you don’t eat a high-protein diet, using a BCAA supplement might help you recover faster after a workout. However, a better approach is to up your protein intake. It will work even better for muscle recovery and improve your strength and muscle gains.
BCAAs, Mental Focus, and Fatigue
Moderate exercise makes you feel happy and energized. But when you train for very long or with very high intensity, your central nervous system goes into protection mode. It makes you extremely exhausted to prevent you from causing bodily harm to yourself.37
When you exercise, your muscles use branched-chain aminos for fuel. That means fewer BCAAs in your blood plasma, which increases the levels of another amino acid, tryptophan, in your brain, contributing to exhaustion.38
By using a BCAA supplement during training, you improve your mental focus and can keep going for longer without feeling overly tired.39 40
Even though you feel better during the workout, BCAAs do not actually make you perform better.41 42
However, feeling more energetic during a workout is not a bad thing, even if it is just a feeling.
The bottom line:
BCAAs might help you feel more alert and less exhausted during intense workouts. It’s likely not relevant for a 30-minute arm workout, but it could be valuable during long and challenging sessions.
BCAAs and Your Immune System
Exercise and an active lifestyle are great for your immune system. However, vigorous training sessions might temporarily lower your defenses for a couple of hours and increase your chances of catching a cold.43 Some researchers challenge this, but it’s still a prevailing theory.44
High-intensity exercise or very long training sessions lowers the glutamine levels in your blood. That is associated with a temporary decrease in your immune function.
Branched-chain amino acid supplementation prevents this decrease, even in elite athletes competing in extreme events like Olympic triathlons.45 Not even a glutamine supplement has the same protective effect as BCAAs for some reason. The reasons why are not fully understood.
A decrease of up to 30% in upper respiratory infection frequency has been observed in athletes taking BCAAs the week following an exhausting competition. However, it is still being determined if that extra amount of BCAAs from regular food has the same effect.
Another study demonstrated that BCAA supplementation eliminated the expected decrease in glutamine levels in elite runners following a race, leading to more efficient immune function.46
The bottom line:
The evidence suggests that BCAAs positively affect immune function. However, there are no studies on athletes eating a lot of protein. If you already get plenty of BCAAs from your diet, supplementing with even more might not do anything.
How Much BCAA Should You Take?
A typical dose of BCAA provides five grams of branched-chain amino acids, often at a 2:1:1 ratio (two grams of leucine per one gram of isoleucine and valine.)
You’re good to go if you get at least three grams of leucine per serving.
Studies examining the effects of BCAAs on fatigue during exercise use higher doses, up to 20 grams an hour before the test or training session.
Ten grams of BCAAs before working out is an effective dosage for reducing muscle soreness.47
Quick questions and quick answers: if you want the skinny without diving into the details, this FAQ is for you.
Are BCAA Supplements Safe?
There are no reports on any toxic side effects of BCAAs in exercise and sports.48 BCAAs are considered safe for healthy people.
Some recent research has shown an association between high intakes of BCAAs and negative health effects, but these are rat studies and do not automatically translate to humans.49
People with amyotrophic lateral sclerosis (ALS) should avoid BCAAs, as one early study had to be shut down by the safety monitoring board when the patients in the BCAA group started dying unexpectedly.50
Can Beginners Take BCAA?
Sure. There are no harmful effects of taking BCAAs as a beginner. Doing so will not help you gain muscle, but that goes for experienced athletes as well.
Should I Take BCAAs or Protein After Working Out?
A protein shake is at least twice as effective for boosting muscle protein synthesis after working out compared to BCAAs. Protein is the superior option.
When Is the Best Time to Take BCAAs?
BCAAs have no known benefits for building muscle and strength, so you can use them whenever you want if you still want to take them. Before, during, or after working out are the most common times.
Do You Need BCAAs if You Take Protein?
No, if you meet your protein requirements through your regular diet you get all the BCAAs you need. If your diet provides enough, you don’t need to take protein supplements either. They are convenient but not necessary.
Are BCAAs Better Than Whey Protein?
No. Your body needs all essential amino acids for building muscle, not just the BCAAs. Whey protein contains all EAAs in abundant amounts and is always the better option, except perhaps for reducing muscle soreness.
Is It OK to Take BCAAs Every Day?
Your body needs BCAAs every day. Getting them from a regular balanced diet is more beneficial, but a BCAA supplement will do no harm.
Is It OK to Drink BCAA Without Working Out?
Yes, it is. Doing so will not help you build muscle, but if you enjoy the taste, go for it.
Can I Mix BCAA With Creatine?
Absolutely. BCAAs increase your insulin levels a bit, and insulin boosts creatine uptake into your muscles. Regular protein or carbs works just as well, but BCAAs will also benefit creatine uptake.
Do Bodybuilders Drink BCAA?
It is one of the most common bodybuilding supplements, even though it has no scientific support. Bodybuilders get big despite drinking BCAA, not because of it.
Do BCAAs Contain Calories?
Yes, they do. BCAAs contain, on average, 4.65 kcals per gram, more than regular protein.51 52 BCAA manufacturers can claim 0 calories on the nutrition label because of a loophole in FDA regulations.53 It’s a lie, though. BCAAs are not calorie-free.
Can I Drink BCAAs While Fasting?
No, BCAAs provide calories and trigger insulin release. They will kick you out of the fasted state for sure.
Are BCAA Supplements a Waste of Money?
If you’re talking about building muscle, the evidence says yes. However, BCAAs might help you maintain focus during long workouts, mitigate muscle fatigue, and reduce muscle soreness.
- BCAA supplementation stimulates muscle protein synthesis, but actual increases in muscle mass cannot happen without the other essential amino acids.
- BCAAs can be compared with LEGO. If you buy a LEGO set with nine pieces, using only three of those pieces during the construction will make the finished model look incomplete compared to the model on the box.
- Branched-chain amino acids are essential for life, health, and performance. They also play a crucial role in building muscle. However, there is no evidence that BCAA supplements help you reach your fitness goals. It is better to supply them through dietary means: whole foods and protein supplements like whey.
That’s it! You’ve reached the end of our guide on BCAA.
Want to learn more about dietary supplements? Which ones are worth your money, and which are questionable or useless? Check our StrengthLog’s Supplement Guide, our free guide where I review 26 of the most popular supplements.
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- CFR – Code of Federal Regulations Title 21