Fact checked by Aimee McNew for Accuracy
Branched chain amino acids, or BCAAs, refer to three essential amino acids that the body requires: valine, isoleucine, and leucine.
These can be found in meats and eggs, but if you’re using intermittent fasting, eating a low protein diet, or otherwise restricting calories, you might be deficient in these vital amino acids.
The Basics of Amino Acids
There are 20 types of amino acids, nine of which are essential because the body can’t make them from other vitamins or nutrients. The essential amino acids include:
Nonessential amino acids can be made from nutrients in the body, but that doesn’t mean they’re not essential for human health.
They’re not required from the diet because they can be made, but if you fall short on these, you’ll still have health issues, immune problems, or other cell-related trauma.
The 13 non-essential amino acids include:
- Aspartic acid
- Glutamic acid
In the body, amino acids are required for building proteins, making hormones, and ensuring you have enough neurotransmitters.
They’re at the root of hundreds of chemical reactions in the body, and too little can result in vital communication issues for your body’s chemical processes.
What Are Branched Chain Amino Acids (BCAAs)?
Branched chain amino acids are named as such because of their chemical structure. They are found in several food sources, like meat and eggs, but are also available in supplement form.
BCAAs typically refer to the supplemental form of amino acids.
Bodybuilders and athletes have been relying on BCAAs since the 1980s because they help muscles repair faster, recover after tough workouts, and rebuild stronger.
If you eat a diet that includes meat on a daily basis, especially with every meal, branched chain amino acid supplements likely don’t have much to offer you.
Where they do have a huge benefit, however, is when you’re taking in less meat because of intermittent fasting or protein fasting. Since the amino acids in BCAAs are essential, you still need them on a daily basis, even if you’re eating less protein.
6 Health Benefits of BCAAs
Branched chain amino acids have been well-studied for several key health benefits. Here are the top six, backed by research.
The immune system relies on amino acids for autophagy, the internal system of self-cleaning that breaks down and destroys cells that are broken or not working correctly.
This material is recycled to make new, better cells, and the overall body is protected from possible effects of cells that are not working as they should. Amino acids are a critical component of fueling this autophagy process, and they’re also used for building proteins that the immune system needs to do its job.
Branched chain amino acids can help boost immunity, especially at times when physical health might be compromised: during illness, after surgery, or recovering from an accident or injury.
They’re even helpful when it comes to fighting off the physical effects of stress, which can wear down the immune system and lead to increased episodes of infection or sickness.
Muscular Repair, Growth, and Prevention of Loss
After a hard workout, muscles need to recover. In order to grow and be built, muscles are constantly torn down and repaired.
Branched chain amino acids can help to alleviate soreness, pain, and other post-workout symptoms by helping to speed up muscle recovery.
You can take BCAAs after workouts, but they’re also effective when used before a workout, to reduce post-workout fatigue.
Branched chain amino acids can also help to prevent muscle loss, as normally happens with aging. When taken, they can help to slow the breakdown of muscle that occurs during the aging process, shown by both human and animal studies.
Support for Intermittent Fasting & Weight Loss
Not only can branched chain amino acids help to support gaining muscle, but they’re also associated with weight loss.
This is because BCAAs can improve muscle and lean body mass while decreasing body fat percentage at the same time when paired with resistance training. Longer term use of BCAAs can also improve body fat to muscle ratios, without leading to a decrease in protein, as shown in animal studies.
If you’re losing weight via intermittent fasting, branched chain amino acids can boost your body’s ability to gain muscle and burn fat, particularly when combined with working out during a state of fasting.
After a fasted workout, taking branched chain amino acids don’t break your fast, leading to continuing fat burning, but the BCAAs will support muscle recovery and repair.
This means that while your body continues to burn fat, it will also be building muscle, bringing a better balance to lean body mass vs. body fat ratios.
Promotes Liver Health
The liver is the body’s largest internal organ, responsible for many things ranging from detox to helping with digestion, to making cholesterol to help transport nutrients throughout the body, and beyond. We need a healthy, fully functioning liver to be well.
Research indicates that branched chain amino acids can support liver health, especially for those with compromised livers, like cirrhosis and liver cancer. BCAAs can improve liver function in those dealing with complications.
Branched chain amino acids are even shown to be protective against liver cancer and hepatic encephalopathy, a condition where the liver is no longer able to detox the blood, putting the body in a critically vulnerable and toxic state.
Protein is a critical nutrient needed for health, but eating high levels of dietary protein can also be hard on the body, especially when it comes to the kidneys and inflammation levels.
Practicing occasional periods of fasting from protein can help to lower inflammation levels and jump start fat loss. It can even slow down the aging process thanks to a decrease in the production of oxidants in the body that lead to cellular breakdown.
The problem with protein fasting, even with those health benefits, is that it can lead to the breakdown of muscle. Enter branched chain amino acids, which can keep muscles nourished and prevent loss while still allowing for a technical state of protein fasting.
Boosts Athletic Performance
If you’re an athlete or are just working to improve physical health with more intense workouts, branched chain amino acids offer many health benefits.
BCAAs are known to increase physical performance in sports or fitness both by reducing post-workout soreness and fatigue and in their ability to build muscle and decrease body fat.
They can also increase physical strength and endurance, leading to better fitness levels and the ability to perform during workouts and sporting events.
Professional athletes, bodybuilders, CrossFitters, and anyone who desires to use more intense workouts to improve body composition can benefit from the use of BCAAs before and after workouts.
In order to determine the best way for them to improve your routine, you should consult a nutritionist and a trainer for personalized dosage and advice.
Cautions & Who Shouldn’t Use BCAAs
It’s always important to remember that no one should start taking any supplements without first clearing it with their practitioner. Certain supplements can interact with other supplements, foods, or medications, and it’s important to ensure you’re not at risk for interactions or side effects before starting something new.
While branched chain amino acids are generally considered to be safe, they still might not be right for everyone. BCAAs can worsen already-existing insulin resistance, so people who are diabetic or have metabolic syndrome shouldn’t supplement with BCAAs unless directed by their doctor or dietitian.
Branched chain amino acids can also increase ammonia levels in the body, resulting in symptoms like fatigue and coordination issues. Maximum daily intake should not exceed 35 grams but might need to be lower for some individuals.
Dosing is important with BCAAs and should be recommended by a professional.
As with most supplements, BCAAs are not proven safe for pregnancy or breastfeeding, so if you could be pregnant, are, or just recently had a baby, you should not take branched chain amino acids. Children under age 18 should also not take them.
There are other medical conditions which they’re not safe for, so if you have any type of diagnosed medical condition, speak with your doctor before starting this or any other supplement, particularly if you have kidney disorders, ALS, or maple syrup urine disease.
Foods High in Natural Sources of Branched Chain Amino Acids
Branched chain amino acids can be found naturally in several food sources. These include:
- Beef (6.8 grams in a 3.5 ounce serving)
- Chicken (5.9 grams in a 3.5 ounce serving)
- Tuna (5.2 grams in a 3.5 ounce serving)
- Salmon (4.9 grams in a 3.5 ounce serving)
- Turkey (4.6 grams in a 3.5 ounce serving)
- Egg yolks (3.3 grams in 2 eggs)
- Whey protein (5.5 grams in 1 scoop)
- Cheese (4.5 grams in ½ cup)
- Greek yogurt (2 grams in ½ cup)
While food sources can provide these essential amino acids for basic health needs, it’s not the most efficient way to use BCAAs for muscle building. Work with a nutrition specialist to ensure you’re getting enough BCAAs in the right format to achieve your health goals.
How to Purchase & Use BCAAs
BCAA supplements are found in most health food stores, online, and from certain gyms or fitness centers. Some health practitioners may also sell them and they can even be found in pharmacies.
The important factors to consider when choosing a supplement are:
- Amino acid ratios: Leucine should be twice as high as valine and isoleucine to ensure a proper, usable ratio
- Inactive ingredients: BCAAs can come in a simple, unflavored powder which is the best way to take them. Some products include preservatives, flavorings, and other ingredients which are not necessary.
- Allergens: When choosing a supplement, always check to make sure that any allergens are not listed in ingredients or in facilities and manufacturing practices.
If you decide to take branched chain amino acids, the best time to take them is directly before working out or right after. BCAAs come in powder form, capsules, and tablets, and many protein powders for pre or post workout drinks add them.
BCAAs are also found in whey protein, bone broth protein, and brown rice protein, but these contain additional ingredients that wouldn’t make them appropriate for protein fasting or intermittent fasting uses.
Figuring out your unique dosage for BCAAs can be a little complicated, which is why working with a practitioner can be helpful. The general recommendation is 91 milligrams for each pound that you weigh.
If you weighed 140 pounds, you would need 12,740 milligrams or 12.7 grams of BCAAs each day. You’d want to split this dose up to a few times daily, like before a workout and after a workout.
Branched chain amino acids won’t give you benefits unless you take them regularly, so you’ll still need to take them even when you don’t exercise.
Branched chain amino acids, or BCAAs, are a collection of three essential amino acids that the body can’t make on its own. They need to be supplied from food sources and are especially vital for healthy muscles, physique, and fitness. They can also be protective against muscle wasting and support the immune system.
Whether or not BCAAs are good for you is determined by a number of health factors, and the best way to see if they can boost your health or fitness goals is to check with your doctor, dietitian, or physical trainer to explore their benefits.
This article was fact checked for accuracy by Aimee McNew, MNT, a certified nutritionist. As always, this is not personal medical advice and we recommend that you talk with your doctor.
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Aimee McNew, MNT, CNTP, is a certified nutritionist who specializes in women’s health, thyroid problems, infertility, and digestive wellness. She ate her way back to health using a Paleo diet, lost 80 pounds, and had a healthy baby after numerous miscarriages. She focuses on simple nutrition practices that promote long-lasting results.