A couple hours ago, an interesting discussion sparked between me and an acquaintance about amino acid supplementation. I had obtained a 5-hour energy, and one of the ingredients is NALT (N-Acetyl L-Tyrosine). Immediately, she stated that amino acids can be fatal if taken in supplemental form via decreased catabolism of other naturally-occurring essential amino-acids. I had honestly never heard of such a claim, so I decided to do a little research. Note: This might get a little science-heavy, but it’s something worth looking into.
The Importance of BCAAs
The first thing I found is that amino acid supplementation (BCAA’s specifically) were shown to increase the lifespan of mice significantly (mice are used in many studies before in-vivo human clinical trials because of their seemingly similar bodily systems). (Side note: BCAA’s are the combination of three amino acids: leucine, isoleucine, and valine). Not only just an increase of lifespan, but it “activates mTOR and eNOS signaling pathways”, increases “mitochondrial biogenesis and ROS defense systems in middle-aged mice”, and “improves age-related muscle deficits” (1). In English, this is basically stating that BCAA’s (the amino-acids particularly popular within the exercise community) are known to help cell growth, survival, increase protein synthesis, promotes vasodilation and circulation via nitric oxide, and help overall body/brain signaling and homeostasis (a stable condition) via oxygen metabolism.
Later in the study, the authors write: “The BCAA, besides increasing average life span in normally fed mice, was found to promote several healthy effects in humans, since it reduced sarcopenia* (Solerte et al., 2008b) and decreased inflammatory markers in chronic heart failure patients (Kalantar-Zadeh et al., 2008)”. *Sarcopenia is the weakening of bones and muscles that comes naturally with aging.
So far, it sounds pretty good, but this debate sparked specifically with N-acetyl L-tyrosine, not BCAAs. So what is tyrosine? I think the first step towards learning about this compound is to break the name down (because people talk more about l-tyrosine rather than N-acetyl l-tyrosine. The N-acetyl prefix means that the l-tyrosine is acetylated, meaning it is less likely to be removed in the liver. With the acetyl group attached to the amino group, the liver is less likely to break down the amino acid (therefore making NALT more bioavailable than just regular l-tyrosine). So for all of my intents, I’ll read into l-tyrosine.