The Many Roles of Amino Acids

If you have heard about amino acids, it is probably in the context of protein. But let’s step back for a second. There is much more to amino acids than simply being building blocks for protein. Amino acids are named as such because they always consist of an AMINO group and an ACID group. That is where the similarity ends, because each amino acid is distinguished by a unique “side chain.” Twenty amino acids are used to create all the proteins in the human body, including muscles. But not all amino acids are used as building blocks for proteins. Amino acids are also the building blocks for hormones, antioxidants, and brain chemicals called neurotransmitters. Moreover, amino acids are conductors in the body, providing signals for cells (including those in the immune system) to communicate with one another. They can also influence how genes express themselves (turning on and off) and how foods are processed to make energy (our metabolic pathways). Let’s look at some amino acids that can be found on the shelves of local health food stores and their unique properties.

• NOW^® L-Lysine 500 mg: The health claim on lysine is “Helps reduce the recurrence of herpes simplex virus (HSV) infection (e.g. cold sores)” and “Helps in collagen formation.” Regarding cold sores, it is believed that lysine helps counter the effects of another amino acid, arginine, which is involved in the replication of the herpes virus. Studies suggest that additional benefits arise from combining lysine supplements with a low-arginine diet, especially during an outbreak. (Mailoo VJ, et al., 2017) High-arginine foods include nuts and chocolate.
• NOW^® Citrulline 750 mg: The health claim on citrulline is, “Precursor to L-Arginine, a non-essential amino acid involved in protein synthesis.” Despite this ambiguous claim, citrulline is often found in the sports section of health food stores. Why? When muscles break down after rigorous exercise, they produce a toxic byproduct called ammonia. Citrulline is involved in the detoxification pathway that safely removes ammonia. Studies suggest that ammonia buildup can delay recovery time for athletes and potentially affect performance. (Suzuki I, et al., 2019) Somewhat related, several studies show citrulline can lower blood pressure (Maharaj A, et al., 2022) by indirectly raising nitric oxide levels in the body, causing blood vessels to expand. More blood flow means increased nutrient perfusion to muscles, which may relate to the recovery benefits it provides athletes.
• NOW^® Glycine 1000 mg: The health statement on glycine is, “Workout supplement for athletic support (as precursor to creatine).” Holding the title for the smallest amino acid in the human body, glycine comes in handy as a building block for many components of the body, including collagen (essential for the structure of bones, skin, hair, nails, etc.), glutathione (a major antioxidant), and creatine (a popular supplement proven to increase capacity for short bursts of intense exercise). Glycine is also commonly found in supplement formulas for sleep or relaxation. In the brain, glycine has a dampening effect on excitability. Preliminary studies have shown it can improve sleep quality, typically at doses of 3 grams before bed. (Bannai M et al., 2012)
• NOW^® GABA 500 mg + B-6: The health claim on GABA is, “Helps promote relaxation.” This description stems from its well-established role as the primary modulator of excitability in the brain. It works in tandem with glycine (described above) to “calm” brain circuits. It appears in many supplement formulas marketed for sleep or anxiety. Many prescription drugs oriented toward pain and anxiety management target the GABA pathway in the brain. Outside the brain, GABA has many peripheral roles, as it is also produced in the intestinal tract, with effects on motility and various secretions. (Auteri M, et al., 2015)

Before starting any new supplements or making any dietary changes, be sure to read the directions and risk information to determine whether they are right for you. The studies and elaborations above are for informational purposes only. Please share them with a trusted regulated health care provider.

Thalia Charney, MA, Holistic Nutrition and Wellness Coach

Nutrition and Health Education Manager, NOW^® Brand

Thalia has a lifelong passion for all things nutrition and healthy living. She has 30 years of experience in the health industry, starting as a fitness instructor and personal trainer, then progressing to 13 years as a holistic nutritionist and wellness coach. For the past nine years, Thalia has held a purely educational role as the exclusive nutrition and education manager of the largest family-owned natural products brand in North America. Her background includes a comprehensive knowledge of herbal medicine, nutrition, essential oils, Vipassana meditation, and vegetarian cooking. Thalia is also the author of “The Confident Food Shopper: The Guide to Food Labels and Fables,” “The Expert Patient: Health is Not a Spectator Sport,” and The 3-Minute Liquid Meal Blueprint.

References
Mailoo VJ, Rampes S. Lysine for Herpes Simplex Prophylaxis: A Review of the Evidence. Integr Med (Encinitas). 2017 Jun;16(3):42-46.
Suzuki I et al. A combination of oral L-citrulline and L-arginine improved 10-min full-power cycling test performance in male collegiate soccer players: a randomized crossover trial. Eur J Appl Physiol. 2019 May;119(5):1075-1084.
Maharaj A, et al. Effects of L-Citrulline Supplementation on Endothelial Function and Blood Pressure in Hypertensive Postmenopausal Women. Nutrients. 2022 Oct 20;14(20):4396.
Bannai M, Kawai N. New therapeutic strategy for amino acid medicine: glycine improves the quality of sleep. J Pharmacol Sci. 2012;118(2):145-8.
Auteri M, et al. GABA and GABA receptors in the gastrointestinal tract: from motility to inflammation. Pharmacol Res. 2015 Mar;93:11-21.

About the Author: NOW

As a family-owned company since 1968 — NOW produces high-quality natural products at prices every Canadian will love. They are a respected leader in the natural products industry, with a mission to provide value in products and services that empower people to lead healthier lives. From field to finished product, NOW prioritizes quality at every step.