Branched-chain amino acids (BCAAs) have been a popular exercise supplement among men for some time. With more women getting into the fitness game, research is looking into the potential benefits BCAAs can have for the opposite gender.
But what exactly are BCAAs, and how can they benefit women specifically?
Let's find out.
What are BCAAs?
As you might have already heard, amino acids are the building blocks for protein.
There are 20 different types, 9 of which are essential and we must obtain them from the foods we eat, the other 11 our body can make on its own [1].
Of the 9 essential amino acids, 3 have a special branched-chain chemical configuration: isoleucine, leucine, and valine.
This chemical branching is believed to provide additional benefits compared to other amino acid structures, including improved muscle growth and recovery post-exercise [2, 3].
One study found that those taking a BCAA supplement of about 5.6 grams after a strength training workout showed an increase in muscle protein synthesis (MPS) of about 22% compared to those in the placebo group.
Just like all essential amino acids, you can obtain BCAAs from high-protein foods such as meat, fish, poultry, eggs, and dairy products.
However, it's difficult to get concentrated amounts from food alone. Because of this, BCAA supplements have become popular, whether on their own or included in higher doses in an essential amino acid (EAA) supplement [1].
BCAA Sources and Supplementation
BCAAs occur naturally in a variety of protein-rich foods, with both animal and plant sources providing these essential amino acids in varying amounts.
Whole Food Sources
Animal Proteins:
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Chicken breast (about 3g of BCAAs per 100g)
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Beef (particularly lean cuts, containing approximately 2.5g per 100g)
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Eggs (a whole egg contains roughly 1.3g of BCAAs)
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Fish (salmon provides about 2.2g per 100g)
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Dairy products like whey protein (one of the richest natural sources with up to 5g per 25g scoop)
Plant-Based Proteins:
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Soy products (tofu contains approximately 1.5g per 100g)
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Legumes like lentils and chickpeas (about 1.2-1.5g per 100g)
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Nuts and seeds (especially pumpkin seeds with roughly 1g per 30g serving)
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Quinoa (a complete protein source with about 0.8g per 100g)
While these food sources provide BCAAs, they come packaged with all essential amino acids and other nutrients that work synergistically. However, to achieve the concentrated amounts used in research studies (often 5-10g), supplementation is typically necessary.
BCAA Supplements
BCAA supplements come in several forms:
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Powders: The most common form, easily mixed with water for pre-, during, or post-workout consumption
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Capsules: Convenient for precise dosing and portability
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Tablets: Similar to capsules but sometimes slower to digest
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Ready-to-drink formulations: Pre-mixed for convenience
When selecting a BCAA supplement, ingredient quality matters significantly. Look for:
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Products with third-party testing for purity
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Minimal artificial additives, flavors, or fillers
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A 2:1:1 or 3:1:1 ratio of leucine to isoleucine and valine (reflecting research protocols)
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Ideally, formulations that include other essential amino acids for complete protein synthesis
The recommended dosage typically ranges from 5–10 grams per day, with many studies showing benefits at the higher end of this range. Timing can be flexible, but many athletes prefer taking BCAAs before, during, or immediately after workouts to maximize their effects on muscle recovery and growth.
Can Women Take BCAAs?
Although women and men differ in many things, their processing of amino acids is the same. Therefore, it is completely safe and appropriate for women to take BCAAs just as men would for their benefits.
The main thing to consider for women when taking BCAAs is their needs.
BCAAs have a lot of great benefits as far as muscle growth and exercise recovery go, but these are most suitable for active individuals. Women who are not active may not need BCAAs or notice many benefits from taking them.
Additionally, women should be wary of taking BCAA supplements, especially during pregnancy, while planning to become pregnant, or while breastfeeding, as some ingredients in various supplements may not be safe during this time.
Always speak to your doctor or healthcare provider before adding a BCAA supplement to your routine, especially if you are taking any medications for a chronic condition.
If you are an active woman who wants to take advantage of BCAAs, consider the following benefits below.
Benefits of BCAA for Women
BCAAs are believed to provide numerous benefits for active individuals, especially women. Below are some of the benefits women may experience from taking BCAAs.
Muscle Growth
The biggest reason many people reach for BCAAs is that they are linked with increased muscle growth when combined with regular resistance exercise.
Specifically, research has found that the BCAA leucine activates a pathway in the body that stimulates muscle-protein synthesis, a.k.a.. the act of creating new muscle tissue [2].
Women tend to have a more difficult time building up muscle mass compared to men because they have lower levels of testosterone. This hormone plays a large role in the process of building muscle. Men biologically have higher levels of muscle mass and higher levels of testosterone compared to women.
While BCAAs are believed to help boost muscle growth, many studies have discovered they work best when combined with the other EAAs, such as those found in a typical whey protein shake, compared to an isolated BCAA supplement [4, 5].
One small study on 24 males taking either 25 grams of whey protein, 6.25 grams of whey protein with a total leucine amount equivalent to whey, or 6.25 grams of whey protein with total EAA equivalent to whey for all EAA except for leucine, found that BCAAs may not be as effective as whey.
This study showed that a lower dose of whey protein supplement with leucine or all other EAA was as effective as 25g of whey protein. Still, only whey was able to sustain increased rates of MPS post-exercise and may be more suitable for attenuating exercise-induced muscle protein breakdown.
Muscle Growth and Repair
Beyond just building new muscle, BCAAs play a crucial role in preventing muscle breakdown during intense exercise. When you work out, particularly during extended sessions or in a caloric deficit, your body can break down muscle protein for energy. The presence of adequate BCAAs helps inhibit this muscle-wasting process.
Leucine specifically triggers muscle protein synthesis by activating the mTOR pathway, essentially flipping the switch that tells your body to build rather than break down muscle tissue. This is particularly valuable for women, who typically start with less muscle mass than men and may find it more challenging to build and maintain lean tissue.
Research has demonstrated that BCAA supplementation can significantly reduce markers of muscle damage, like creatine kinase, after high-volume resistance workouts. This indicates less muscle damage and potentially more efficient recovery [15].
According to a systematic review and meta-analysis of BCAA supplementation and muscle damage biomarkers, BCAAs may be useful in lowering creatine kinase (CK) and delayed-onset muscle soreness (DOMS) after exercise-induced muscle damage.
For women engaged in regular strength training, this dual action of promoting growth while preventing breakdown creates an optimal environment for gradual lean muscle development without excessive bulk.
Post-Exercise Recovery
In addition to boosting muscle growth, BCAAs can help boost post-exercise recovery and reduce muscle soreness.
Following a strenuous workout, it's common to experience muscle soreness, also known as delayed-onset muscle soreness (DOMS). While the exact cause of DOMS is not completely understood, it is theorized that it is a result of tiny tears in the muscle fibers from resistance exercise [6].
Taking BCAAs may help to reduce the damage caused to the muscle tissue during exercise and therefore reduce the symptoms of DOMS [7].
Women, especially those who are new to exercise, are more likely to start a routine and then give it up when DOMS rears its ugly head. Fewer issues with DOMS typically mean a higher likelihood of sustaining a consistent exercise routine, which is required to build muscle.
BCAAs have shown particular promise in reducing soreness after high-volume squat exercises and other intense lower-body workouts, training sessions that often leave even experienced athletes struggling with mobility for days. By minimizing this recovery period, women can maintain more consistent training schedules, potentially leading to better long-term results.
Another significant benefit is BCAAs' impact on central fatigue during exercise. By competing with tryptophan for transport into the brain, BCAAs can help reduce serotonin production during workouts, potentially delaying the onset of mental fatigue and allowing for more productive training sessions.
Metabolic Function
Research has long regarded a high-protein diet for boosting metabolic rate and aiding in weight loss, specifically in overweight and obese individuals.
More recent studies have found that consuming a high-protein diet with an emphasis on BCAAs may help to further boost fat loss and improve metabolic function and body composition [8].
Women tend to have a slower metabolic rate than men because of their differences in body size and composition. Men biologically have higher levels of muscle mass, which equates to a faster metabolism.
Therefore, women who are hoping to improve their metabolic rate can not only boost their muscle growth with BCAAs but also potentially boost fat loss.
Metabolic Function Regulation
BCAAs play a multifaceted role in metabolic regulation that extends beyond simple weight management. They're actively involved in how your body processes and utilizes energy from food.
These amino acids participate directly in regulating blood glucose and insulin sensitivity. Research suggests they may help maintain healthy blood sugar levels by promoting glucose uptake in muscle cells rather than fat cells. This aspect of BCAA function can be particularly beneficial for women concerned about metabolic flexibility and insulin responsiveness.
During exercise, BCAAs serve as an alternative energy source through amino acid metabolism. When glycogen stores begin to deplete during extended workouts, BCAAs can be converted into acetyl-CoA and enter the citric acid cycle, providing fuel for continued activity and potentially reducing exercise-induced fatigue.
This metabolic pathway explains why BCAAs may help women maintain energy levels during longer training sessions. By altering brain serotonin levels, they can potentially delay the perception of fatigue, allowing for more productive workouts.
One small study found that BCAA supplementation could enhance time-trial performance in two consecutive days in endurance runners (both men and women) by blocking serotonin synthesis and preventing excess ammonia levels.
Beyond fitness applications, BCAAs have shown therapeutic potential for certain metabolic conditions. They've been studied for their beneficial effects in conditions like hepatic encephalopathy and liver disease, where they support protein metabolism and help regulate the body's fuel utilization processes.
For women with existing metabolic concerns like impaired fasting glucose or type 2 diabetes, it's essential to consult with a healthcare provider before supplementing, as BCAAs' effects on glucose metabolism can vary depending on individual health status.
Hormone Balance
Additionally, emerging research has found that the use of BCAAs may be helpful for hormonal balance in women. Some studies suggest that BCAAs may increase the hormones leptin and adiponectin [9, 10].
Leptin is an essential hormone for regulating appetite, while adiponectin helps the body use fat as energy. BCAAs may also help to increase glucagon, which is essential for maintaining blood sugar levels, which influences hunger levels and cravings.
Increases in these hormones can help to better control weight and metabolic function.
Hormone Balance in Detail
The relationship between BCAAs and hormonal regulation in women deserves particular attention, as it may offer benefits beyond purely physical performance improvements.
BCAAs appear to influence several key metabolic hormones that play crucial roles in appetite control, fat conversion, and overall metabolic health. Research indicates they may help optimize leptin sensitivity, potentially supporting more effective appetite moderation and preventing the leptin resistance that often accompanies weight gain.
Adiponectin, another hormone affected by BCAA intake, helps regulate glucose levels and fatty acid breakdown. Higher levels of this hormone are associated with better insulin sensitivity and reduced fat storage accumulation. By potentially supporting healthy adiponectin levels, BCAAs may help women maintain more balanced body composition.
BCAAs also impact glucagon, a hormone that works in opposition to insulin to maintain stable blood sugar levels. This hormonal balancing act is particularly relevant for women concerned about metabolic health, as it supports consistent energy levels and may reduce cravings for carbohydrates.
Some early research even suggests BCAAs might have applications for mental health conditions affected by hormonal fluctuations, though this remains an emerging area of study. They've also been investigated for potential benefits in recovery from traumatic brain injuries and fighting certain bacterial and viral infections through immune system support.
For pregnant women, however, caution is warranted. While protein intake is important during pregnancy, excessive BCAA supplementation could potentially affect fetal growth or interfere with the delicate hormonal regulation necessary during this period. Always consult a healthcare provider before using any supplements during pregnancy or breastfeeding.
BCAAs in Diet
Integrating BCAAs effectively into your overall nutrition strategy requires thoughtful planning, especially for women focused on improving body composition and building lean muscle mass.
Rather than viewing BCAAs as a standalone solution, consider them as part of a comprehensive approach to protein intake. For most active women, aiming for 1.6-2.0 grams of protein per kilogram of body weight daily provides sufficient amino acids to support muscle maintenance and growth. Within this broader protein framework, BCAAs should comprise roughly 15-25% of total protein consumption.
Tracking your dietary records for a few days can help identify your baseline BCAA intake from protein-rich foods. This information allows for more personalized dosage decisions regarding supplementation—you might need less than the standard recommendations if your diet already contains substantial complete protein sources.
The timing of BCAA consumption deserves consideration within your nutrition strategy. While they can be taken at various times, research suggests potential benefits when consumed:
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Before fasted morning cardio to minimize muscle breakdown
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During longer training sessions (over 60 minutes) to reduce fatigue
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Immediately after workouts, to jumpstart recovery
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Between meals, when protein intake might otherwise be low
For women with specific health considerations like type 2 diabetes or metabolic disorders, the interaction between BCAAs and blood glucose regulation becomes particularly important. In these cases, monitoring blood sugar responses to BCAA supplementation is advisable, as individual responses can vary significantly.
Plant-based athletes may need to be especially mindful of their BCAA intake, as plant proteins typically contain lower concentrations of these amino acids compared to animal sources. Supplementation might play a more crucial role in meeting optimal levels for those following vegetarian or vegan diets.
Don't We Get BCAAs from Food?
BCAAs are present in high-protein food sources such as meat, fish, poultry, eggs, dairy, and some plant sources such as soy.
While we do obtain BCAAs naturally from protein sources in our diet, it's difficult to consume concentrated amounts of just BCAAs unless a supplement is used.
Who Can Benefit Most From a BCAA Supplement?
Athletes and active individuals would benefit the most from taking a BCAA supplement. However, it should be noted that this is only if they are getting adequate amounts of EAAs in their diet as well.
“As a Registered Dietitian Nutritionist, I have worked with many women on improving their body composition by utilizing BCAAs as a powerful tool to get more from their workouts.”
Although BCAAs are associated with many benefits, you get the most out of them when you are taking them with adequate amounts of EAA to help with muscle building and repair.
When to Take BCAAs for Best Results?
There is much debate regarding when the best time to take BCAA supplements is. Some research suggests the timing of BCAA intake is less important compared to dosage and consistent usage.
Of the studies available, it appears that taking BCAAs before, during, or after a workout showed little difference [11].
For example, one study on men who took 25 grams of whey protein isolate (that contained 5.5g of BCAAs) either before or after weight lifting for 10 weeks saw the same improvements in strength and muscle growth.
Some studies have found BCAA levels in your blood peak at about 30 minutes, but the window of time you can take BCAAs for best results may be as long as 5 hours post-exercise [12, 13].
Therefore, it's still unknown what time is best to take BCAA supplements. Instead of worrying about exact timing, focus on consistently taking your BCAA supplements sometime before or after exercise, depending on what works best for you.
Is it OK to drink BCAAs Every Day?
Taking BCAA supplements daily is not associated with any adverse side effects or health concerns. Taking amino acids daily may provide greater benefits in terms of muscle growth and recovery.
Be mindful of dosage and usage recommendations provided, as excessive amounts of BCAA may cause long-term health effects.
Potential Risks and Side Effects
While BCAAs offer numerous benefits, it's important to be aware of potential risks and considerations, particularly for certain populations:
Metabolic Concerns: Some research has suggested that elevated BCAA levels may be associated with insulin resistance and potential links to type 2 diabetes in certain individuals. Those with impaired fasting glucose or existing metabolic conditions should approach supplementation cautiously.
Liver Considerations: People with existing liver conditions, including liver cirrhosis, hepatic encephalopathy, or hepatocellular carcinoma, should consult their healthcare provider before supplementing. BCAAs are metabolized primarily in the liver, and altering their concentrations could potentially impact liver function in those with compromised hepatic health.
Branched-Chain Ketoaciduria: This rare genetic disorder, also known as maple syrup urine disease, impairs the body's ability to process BCAAs properly. Individuals with this condition must strictly avoid BCAA supplementation as it could have serious negative consequences.
Medication Interactions: BCAAs may interact with certain medications, including those for diabetes, Parkinson's disease, and some antibiotics. Always disclose supplement use to your healthcare provider when discussing medications.
Chronic Alcoholism: Those with a history of chronic alcoholism may process BCAAs differently and could potentially experience adverse reactions to supplementation.
Cardiovascular Considerations: Some preliminary research suggests that certain BCAA metabolites might be associated with cardiovascular disease risk, though more studies are needed to fully understand this relationship.
The key principle with BCAA supplementation, as with any nutritional intervention, is individualization. What works well for one person may not be optimal for another, particularly when underlying health conditions are present. Starting with lower doses, monitoring your body's response, and consulting with healthcare professionals when appropriate can help minimize potential risks while maximizing benefits.
Is BCAA Good for Belly Fat?
Because BCAAs may help to increase fat burning and support metabolic functioning, they can be beneficial for those who struggle with abdominal fat.
Although you cannot target fat loss in a specific area, working on building muscle mass can help to increase metabolism, reduce body fat composition, and improve the health and appearance of belly fat.
Does BCAA Increase Testosterone in Females?
BCAA supplementation can increase testosterone levels in females as well as males.
Testosterone is an essential hormone in muscle building; however, testosterone increases in females regardless of the presence of resistance training. These rises are often less than those in men and are temporary [14].
In summary, taking BCAAs will not lead to a significant boost in testosterone in women that would result in alterations in overall hormone balance. Instead, it functions as a way to boost muscle growth.
This article is for informational purposes only and is not a substitute for professional medical advice. Always consult a healthcare provider before starting any new supplement or fitness regimen.
Further Reading: BCAAs vs. Creatine: For Muscle Growth and Beyond
