L-Glycine is an amino acid, in fact it is the smallest amino acid there is. Known as the building blocks of life, amino acids are what make up proteins and are crucial for almost every cell function in the body. Whilst in the fitness community most of us think of the muscle building effects of amino acids, outside of the fitness community amino acids are famous for their formation of neurotransmitters.
Neurotransmitters are chemical signals found in the brain and central nervous system that runs throughout the body. While some neurotransmitters create a wakefulness effect in our mind and body, others do the opposite and help us relax and calm down - which is where Glycine shines.
Glycine for Sleep
Glycine is known as a non-essential amino acid, meaning our body can produce it naturally and supplementation isn’t necessary, although as we will discuss it is beneficial to get extra Glycine through supplementation. A normal carnivorous diet can provide about two grams of Glycine a day coming from protein-rich foods such as meat, fish, dairy and legumes. This amino acid can be utilized by virtually anybody without any negative side effects. Its most popular and widely utilized effects revolve around increasing sleep quality.
* In one study, volunteers who complained of sleep problems took either three grams of Glycine or a placebo before going to sleep and were then evaluated upon waking. In the group given Glycine, participants reported significant improvements after sleep across fatigue, liveliness, peppiness, and mental clarity(1).
* In another study, 10 healthy male volunteers who had no sleep complaints were evaluated for sleep quality spending their usual time in bed, which was an average of 7.3 hours. These participants were then either given a placebo or three grams of Glycine and reduced their time in bed to 5.5 hours for three consecutive nights. At the end of the study, researchers reported Glycine was associated with significant improvements in fatigue, daytime sleepiness, and daytime performance after nights where sleep was restricted.(1)The best way to supplement Glycine into your diet is to start with a gram (either in powder or pill form) around an hour before bed. Some will feel immediate improvements in their sleep in the form of feeling more wakeful the next day, and/or sleeping through the night without waking up. For all individuals that don’t have any changes in their sleep with one gram, double the dose a few nights later, and again a few days later until the desired effects are achieved.
Most achieve a better night sleep and more energy throughout the day as a result with no more than three grams (three grams was the amount used in both above-mentioned studies). If you are still not getting the sleep improvements you would like, five grams is the most you should take in one dose, and most won’t even need that much to reap these benefits.
Other Uses of Glycine
While Glycine is mainly supplemented for sleep improvements, many other various (and seeming random) benefits exist. Glycine is used for treating schizophrenia, benign prostatic hyperplasia (BPH), and some rare inherited metabolic disorders as well as improving memory enhancement. It is also used to protect kidneys from the harmful side effects of certain drugs used after organ transplantation, as well as protecting the liver from harmful effects of alcohol.
Other uses include treating leg ulcers, when applied as a cream that also contains other amino acids. Some researchers think Glycine may have a role in cancer prevention because it seems to interfere with the blood supply needed by certain tumors.(2)
Take Home Message about Glycine
This versatile amino acid has a long list of benefits and with the majority of Americans suffering from some sort of sleep disorder, Glycine might be the fix you need. Mix three grams into a bedtime snack whether it be cottage cheese, oats, Greek yogurt, or a casein shake and enjoy your longer REM sleep stages and uninterrupted rest!
Also, since most Glycine supplements are derived from sugarcane, it naturally has a sweet taste! Limiting any cravings for late night simple carbs and adding another benefit to the list, making this amino acid one of my staple ingredients I add to all my late night snacks, and one you should too. Thank you as always for reading to the end and I hope you learned something valuable here today!!
Our articles should be used for informational and educational purposes only and are not intended to be taken as medical advice. If you're concerned, consult a health professional before taking dietary supplements or introducing any major changes to your diet.
1 “Can Glycine + Amino Acids Be the Secret to Deep, Rejuvenating Sleep?” Proheath.com. N.p., 1 Jan. 2015. Web. 21 July 2016.
2 “GLYCINE.” Webmd.com. N.p., n.d. Web. 21 July 2016.
3 Bannai, Makoto, Nobuhiro Kawai, Kaori Ono, Keiko Nakahara, and Norobu Murakami. The Effects of Glycine on Subjective Daytime Performance in Partially Sleep-Restricted Healthy Volunteers. Ncbi.nlm.nih.gov. N.p., 18 Apr. 2012. Web. 21 July 2016.