Glycine is a proteinogenic amino acid, which means it is among the amino acids biosynthesized into proteins. It is the simplest (and smallest) amino acid. While glycine is biosynthesized from the amino acid serine, glycine is a popular supplement due to its many benefits affecting fatigue, skin health, mental health, and inflammation.

What Does Glycine Do?

Glycine has several health benefits that make it attractive as a supplement. Glycine has a calming effect in the brain which helps promote sleep. It also helps to lower your body temperature at night which makes sleep more effective. In addition, glycine reduces skin wrinkles and suppresses UV-B-induced skin damage and photoaging. It has also been known to help in the treatment of obsessive-compulsive disorder and schizophrenia.

Helps you Sleep

One of the most popular reasons people turn to glycine is because of its impact on sleep. When oral glycine is absorbed, it increases serotonin levels without increasing dopamine levels. This helps normalize circadian rhythms, creating a better sleep routine in your body.

Improves Sleep Quality

When glycine is diffused through the blood-brain barrier, it acts primarily on NMDA receptors. The actions are thought to help inhibit muscle activity during the REM stages of sleep and for lowering core body temperatures. Both of these effects result in deeper, more restful sleep.

Decreases Fatigue

While glycine doesn’t actually decrease fatigue, its effects in normalizing your sleep patterns and in making sleep more effective help reduce patterns of fatigue. It also helps you feel more rested on less sleep since your sleep is more effective.

In a study published by the Sleep and Biological Rhythms Society, researchers found that glycine produced an improved feelings of clear-headedness and liveliness after consuming glycine before bedtime.

In a second study, volunteers were evaluated after 3 nights of sleep deprivation. The participants in the study had their sleep reduced by nearly 2 hours per night for 3 consecutive nights. Those who were given glycine before had significantly less fatigue, less daytime sleepiness, and higher daytime performance than those who ingested a placebo.

Improves Memory and Learning

Glycine can also help improve memory and learning. This topic was explored by, which said: “Glycine is involved in signaling through the hippocampus, and it seems that both the glycinergic and the glutaminergic systems can be involved here.”

Helps Treat Mental Illness

Researchers have seen positive effects in glycine treating obsessive-compulsive disorder, body dysmorphic disorder, and in reducing symptoms of schizophrenia.

It may also help reduce effects of depression, especially if you have low glycine levels. Depression is associated with low glycine blood levels as well as high taurine levels.

Reduces Wrinkles

While glycine’s biggest claim to fame has been its effects on sleep, it’s second most renown effects are on skin health. Glycine has shown to significantly improve skin elasticity and improve moisture and water retention when glycine was consumed through collagen peptide. Women who took a glycine-based supplement for 4 weeks saw eye wrinkles reduce by 20%, with positive effects lasting after the study ended.[1] At 8 weeks, collagen had improved procollagen type 1 by 65% and elastin by 8%.[2]

When Should I Take Glycine?

It is recommended to take glycine with a meal before bed, as taking glycine on an empty stomach can sometimes cause nausea. Because of its sedative-like effects on sleep, it’s more helpful before bed than in the morning or midday.

While most people don’t experience side effects, many nutritional experts will recommend starting slowly (1 gram before bed for several days, then increasing incrementally if results are not experienced).

*The information in this article has not been evaluated by the Food & Drug Administration or any other medical body. We do not aim to diagnose, treat, cure or prevent any illness or disease. Information is shared for educational purposes only. You must consult your doctor before acting on any content on this website, especially if you are pregnant, nursing, taking medication, or have a medical condition.