In the world of bodybuilding, performance nutrition, and sports supplements beta alanine (sometimes referred to as CarnoSyn (its trademarked name) or as b-alanine) has become synonymous with high-performance workouts, increased endurance, boosted strength, and extra power. It’s also become near impossible to mention beta alanine without mentioning the “beta alanine itch.”
Almost everyone who’s ever taken a supplement containing beta alanine can attest to the infamous beta alanine itch: the sure-fire tingling and itching of the neck, shoulders, and arms that starts about 15 minutes after you take your pre-workout and goes away after a half hour or so. While it may be a harmless side effect, it’s left more than one person wondering, “Why does that even happen?”
The Science Behind the “Beta Alanine Itch”
While there’s plenty of research supporting claims about beta alanine’s workout-enhancing abilities (thanks largely in part to its relationship with carnosine, a muscle synthesizing dipeptide cousin), there are a few pieces of the beta alanine itch puzzle that researchers have yet to find. Keeping that in mind, here are some of the pieces that have been found:
Beta Alanine: The Histamine Response
As it turns out, the characteristic itch can be attributed, at least in part, to a kind of histamine response (one that’s related, in some ways, to how our bodies can react to certain allergens). While numerous researchers have been able to recognize and support the theory that the itch is the result of a histamine response, the actual mechanisms that allow the response to happen are still up for debate.
In one 2012 study researchers tested the effects of beta alanine and L-alanine by administering both amino acids intradermally (i.e. between the layers of the skin). Their findings supported the histamine response theory and the theory that the primary mechanism for this particular response is a yet to be identified histamine-independent neural pathway (which is a fancy way of saying that the response works independently of our larger histamine system to get our nerve endings excited).
The “beta alanine itch” is a fascinating piece of bodily phenomena (even if it can be a slightly annoying one). The other good thing about the itch, which some regular users may be able to attest to, is that the effect has been shown to wear off over time. Itchiness acknowledged, beta alanine is one amino acid where the potential benefits outweigh definitely outweigh the side effects.