Can you take bcaa during intermittent fasting

Can You Take BCAA During Intermittent Fasting?

Written by Andrew Brewer. ⚕️Reviewed and fact checked by our medical team.

Can you take bcaa during intermittent fasting

It can be challenging to find the energy to workout while intermittent fasting, so you may be considering taking BCAA, or branched-chain amino acids. BCAAs are thought to help you build and repair your muscles, improve your performance and endurance, and reduce fatigue. This wonder supplement is a must-have for fitness enthusiasts. Because it’s growing in popularity every day, you may be wondering if you can take it during intermittent fasting windows. Unfortunately no, taking BCAA during fasting will break your fast; however, there are some cases that you may want to make a small exception to the rule.

While BCAAs are mostly absorbed directly into your muscles, they do contain calories. Because of this, they trigger a response within your body, even if it’s not insulin. You’ll want to avoid taking BCAA during fasting if you keep to a strict schedule, but they are safe to take during eating windows with little restriction as long as you take as directed. Let’s explore more about some of the benefits of taking BCAA and how to safely integrate these wonder amino acids into your diet.

Key Takeaways

  • BCAA supplements can be beneficial for building and repairing muscles, improving performance and endurance, and reducing fatigue during workouts.
  • BCAA supplements contain calories and will break your fast, so they should be avoided during fasting windows if you are following a strict schedule.
  • If you are more focused on your insulin response, BCAA supplements may not be the best choice, even if you take them within your eating window.
  • While BCAA supplements are generally safe to take during eating windows, it’s important to follow the recommended serving size and not overconsume.
  • BCAA supplements are not a replacement for a well-balanced diet rich in BCAAs, which can be found in foods such as chicken, eggs, dairy, fish, nuts, and legumes.

Benefits of BCAA

BCAA is made of three essential amino acids: valine, isoleucine, and lucine. These amino acids are important for our muscles, particularly to help them grow and repair. Some people take BCAA before working out to help give them a boost of energy and help build their muscles, while others take it as a post-workout to prevent fatigue.

Both will help target the nutrients when and where you need them most. Your body doesn’t naturally produce BCAA, so you get them from a well-balanced diet. Foods like chicken, eggs, dairy, fish, nuts, and legumes are rich in BCAAs among other vitamins, minerals, and other nutrients. If you’re not getting enough BCAAs in your diet, you can also take supplements to boost your intake. BCAA also comes in powder form that you can mix with water or milk depending on your preference.

You’ll feel so much better during and after your workouts when you increase your BCAA intake, but skip them during your fasting windows. They will cause you to break your fast.

Why Does BCAA Break Your Fast

BCAAs are similar to proteins. Just as a protein shake would break your fast, so do BCAA supplements. Most BCAAs contain calories, which inherently will break your fast, even if it’s only a few. Even if it doesn’t feel like it, you’re technically eating when you take BCAA supplements, no matter what form.

If you’re more focused on your insulin response over a few calories, BCAAs will not take you out of ketosis. If you take as directed, the recommended serving size is too small that it likely won’t have an effect on your insulin levels. The key word is likely. If you take too much, it may take you out of ketosis. Too, everyone’s body is different, so what doesn’t prompt a response in one may in another. More research is needed to determine the effect of BCAAs on your glucose levels. If you are following a strict fasting schedule, it’s best to skip them during fasting windows. They have caloric value even if they don’t impact your metabolic response.

However, if you are focusing on fasting and working out, you may want to take the supplements to ease your fatigue and improve your energy during your sessions. They will break your fast, but it’s up to you how strict you want to follow the rules. Ultimately, BCAA supplements are beneficial, but you have to decide if you want to reap the full benefits of intermittent fasting or bend the rules to help build more muscle.


  • Can you take BCAA during intermittent fasting?

Yes, taking BCAA (Branched-Chain Amino Acids) supplements during intermittent fasting is generally safe and can help preserve muscle mass and reduce muscle breakdown.

  • What are BCAAs?

BCAAs are a group of essential amino acids that the body cannot produce on its own and, therefore must be obtained through diet or supplementation. The amino acids that make up BCAAs are leucine, isoleucine, and valine.

  • Why are BCAAs important during intermittent fasting?

During fasting, the body breaks down stored glucose and fat for energy. However, it can also break down muscle tissue for energy, leading to muscle loss. BCAAs can help prevent muscle breakdown and preserve muscle mass during fasting.

  • When should you take BCAAs during intermittent fasting?

It’s recommended to take BCAAs before and/or after your workout during your fasting window. This helps ensure that your muscles have access to the amino acids they need for growth and repair.

  • How much BCAA should you take during intermittent fasting?

The recommended dosage of BCAAs is typically around 5-10 grams per serving. However, following the dosage instructions on the specific supplement you are using is important.

  • Are there any side effects of taking BCAAs during intermittent fasting?

BCAA supplements are considered safe when taken in recommended doses. However, some people may experience mild digestive issues such as nausea, stomach discomfort, or diarrhea. Therefore, it’s important to consult with a healthcare provider before adding any supplements to your diet.

Andrew Brewer

Andrew Brewer

Andrew Brewer started to give people the guidance that he never received when he was first starting. His goal is to make your goals achievable and to offer you only the best fasting apps that the internet has to offer. You're not on your own - Andrew and the entire family of reviewers at are here with you every step of the way!