What Are BCAAs and What Do They Do?

BCAAs stands for Branched Chain Amino Acids. These are a specific group of three amino acids that have gained significant attention – especially in the fitness world. 

They are commonly taken to boost exercise performance and increase muscle mass.

This article will explain what exactly BCAAs are, as well as delve into the benefits of BCAAs for improving our health. 

What are BCAAs?

There are three branched chain amino acids: leucine, isoleucine, and valine. 

These amino acids account for about 35-40% of our body’s protein, and they make up about 14% of the amino acids in muscle (1).

BCAAs are considered “essential”, meaning the body does not make them on its own. Instead, we must get them from food and/or supplements. 

BCAAs can be found in most protein-rich foods like eggs and meats, but sometimes diet alone is not enough – especially for more intense physical training. 

Similar to other amino acids, they are building blocks of protein. However, their “branched-chain” structure allows them to be used in a unique way. 

BCAAs can improve exercise performance, increase muscle mass, boost the immune system, enhance liver health, and perhaps even help promote a healthy weight. 

What are the benefits of branched-chain amino acids?

Most amino acids are broken down in the liver, however, BCAAs are broken down in muscles, giving them a more targeted effect. 

BCAAs also have widespread health benefits throughout the body. Continue reading to learn more about how exactly BCAAs can improve your health. 

Reduce muscle fatigue and improve exercise performance

BCAAs can improve athletic performance, therefore helping to support your strength and endurance goals.

But, how do BCAAs do this? 

Branched chain amino acids may increase circulating oxygen levels, which helps improve endurance and reduces fatigue during exercise (2).

They also help preserve glycogen stores. Glycogen is the body’s primary fuel source stored in muscles. During exercise, the body taps into this storage for energy. 

When glycogen stores are depleted, the body begins to feel fatigued, and performance is hindered. However, thanks to BCAAs, glycogen stores can be preserved during a workout, which can keep you going strong. 

In fact, BCAAs may even reduce serotonin levels during exercise. 

Serotonin is elevated during exercise, however, this hormone also contributes to feelings of tiredness and fatigue during a workout. Therefore, by reducing serotonin, it takes longer for your body to feel tired (3). 

While the benefits of BCAAs are still being studied, health and fitness professionals absolutely acknowledge the power of BCAAs to improve body composition and physical performance.  

May reduce muscle soreness

In addition to helping improve physical performance, BCAAs have been shown to reduce muscle soreness, which in fact may contribute to their performance-boosting effects. 

BCAAs reduce muscle soreness and help repair damaged muscle fibers quickly (2, 3).

This increased recovery time not only contributes to muscle growth, but can get you back in the gym more quickly to continue working towards your goals. 

Promotes lean muscle mass

Leucine, one of the three BCAAs, activates a pathway that directly stimulates muscle protein synthesis (4).

Muscle protein synthesis is a necessary process for building and repairing muscle. 

Largely due to leucine’s effects, taking BCAAs has been shown to significantly increase muscle protein synthesis after a workout.

However, BCAAs have been shown to promote lean muscle mass when people are already consuming adequate dietary protein. 

That’s why it’s important to make sure you are consuming adequate protein, first and foremost. If you are falling short of your body’s protein needs, supplementing with BCAAs may not lead to increased muscle mass (5).

May help maintain a healthy weight

What’s more, some research shows that BCAAs may help increase fat loss, while preventing fat gain. 

Adults who consume BCAAs tend to be less likely to be overweight than those who don’t. 

But, how exactly does this happen?

One explanation is that BCAAs may improve blood sugar regulation, which in turn can help support a healthy weight (6).

Another explanation is that BCAAs help contribute to total dietary protein intake, and high protein diets have been associated with enhanced fat loss (7).

However, the studies on BCAAs and weight status have been somewhat flawed and inconsistent. 

So, while BCAAs may in fact be an important supplement for weight management, more research needs to be done to determine if BCAA supplements provide any added benefit more so than a high-protein diet. 

May promote liver health

Branched chain amino acids are particularly useful in promoting a healthy liver, especially in those with liver disease. 

In hospitals, BCAAs are administered to patients with liver disease to reduce liver damage and improve liver function (8).

In fact, BCAAs can help regenerate healthy liver cells, which is quite important for someone with a damaged liver. 

However, for the average healthy person without liver damage, BCAAs are not supported for general liver health benefits. 

May boost immune function

What’s more, studies show that supplementing with BCAAs can help improve the immune system. 

This is especially true during sporting events or long periods of intense physical activity, when the immune system can be suppressed (3).

BCAAs are necessary for immune cells to function properly. This is largely due to the fact that BCAAs help cells – like lymphocytes – make protein, which is essential for their role in the immune system (4).

What are the top food sources of BCAAs?

The main dietary sources of BCAAs are dairy products and meat – specifically, red meat. This includes beef, bison, lamb, goat, cheese, milk and yogurt. 

Although most protein-containing foods contain BCAA, some foods are richer in BCAAs than others. 

Other excellent sources include chicken, fish, and eggs. BCAAs are also found in beans, lentils, nuts, and soy products, however, to a lesser extent than animal products. 

How much BCAAs per day?

In general, it’s recommended that women take about 9 grams of BCAAs daily, while men aim for around 12 grams per day. 

Recent research suggests that daily requirements may actually be as high as 65 mg/lb (144 mg/kg) of body weight per day (1). 

Based on this daily requirement, a 175-pound male would require about 11 grams of BCAA daily. 

People who are especially active, consuming as much as 18-20 grams of BCAAs daily has been shown to be beneficial. 

When should I take BCAAs?

The best time to take BCAA supplements is before and/or after your workout. 

For especially intense exercise – particularly with strength-training workouts that last over an hour – it’s best to consume BCAAs during the workout as well. This helps with sustaining energy levels for the duration of your workout. 

Some studies suggest that BCAAs are most effective on an empty stomach. However, this research is not conclusive. 

It’s most important that you are taking BCAAs consistently to reap the most benefit. 

So, this may mean that you feel best when consuming BCAAs with a pre-workout shake or meal. Others may feel their best when taking BCAAs on an empty stomach. 

What’s more, some studies show that taking BCAAs with glutamine is more effective and performance-boosting effects are even greater compared to taking BCAAs alone. 

Try this recipe for an energy-boosting muscle recovery shake that you can try before or after your workout:

Vanilla Latte Smoothie


  • 2 scoops of Naked Vanilla Whey
  • 1 scoop of BCAA powder
  • ½ frozen banana
  • 1 oz of espresso or 1 tsp of espresso powder
  • 1 cup of vanilla almond milk 
  • 2-3 ice cubes

Directions: Blend ingredients together and enjoy before or after a workout!