What is the difference between protein supplements and branch chain amino acid supplements? Isn't protein composed of amino acids? Are there scientific studies showing the benefits of BCAA supplement as compared to protein supplements?

3 Answers 3


Branch-chain amino acids (BCAA) are a set of amino acids with a particular chemical structure involving an aliphatic side-chain with a multiple carbon-bond. There are three relevant BCAA: leucine, isoleucine, and valine; these are three of the nine essential amino acids for humans.

BCAA by themselves could be considered a protein supplement, but they are not complete for dietary purposes as a BCAA-only mix does not contain all nine essential amino acids (or more, for efficiency). Any commercial protein mix could have some or all BCAA, but that's going to vary.

BCAA supplementation has been demonstrated to decrease muscle damage and increase muscle-protein synthesis. A couple relevant studies:

  • I thought that the more broken the muscle is the bigger it can grow back. If BCAAs reduce tearing, aren't they bad for bodybuilding?
    – JoJo
    Commented Mar 29, 2011 at 3:03
  • @JoJo That's not necessarily so. I don't believe that it's definitively known (would love to see some research on this, if it exists) that muscle damage is a requirement for growth. Many would claim that muscle damage is a by-product of the exercise that generates the correct hormonal state for muscle growth; in this scenario, damage must be repaired before growth can begin and is therefore detrimental.
    – G__
    Commented Mar 29, 2011 at 3:32
  • Another paper on the topic ncbi.nlm.nih.gov/pubmed/19828686 Commented Mar 29, 2011 at 12:48

A lot of protein supplements out there already have BCAA in them. BCAA are the type of amino acids that your body cannot naturally produce, so taking them in addition to protein might be a good idea. BCAA's are known to be anti-catabolics which is beneficial for recovery when working out.


Even though the answer has already been accepted, thought I'd throw in my two cents. I've been on protein shakes for a year or so and going to the gym and other activities. After going to the gym I'd get extremely exhausted and it would take me a week to recover each time. So I went to the nutrition store and they suggested I take BCAA and right away I noticed that I would recuperate a lot faster after going to the gym. So for me, this really worked.

So what's the difference, when you got the answer already checked. Does it work? Heck yeah.


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