Glycine: The Sleep Building Block
When most people think of amino acids, they immediately think of muscle building, with branch-chain amino acids and essential amino acids being at the forefront of muscle-building marketing for decades. However, amino acids are capable of way more than just packing on muscle.
Glycine is one of the 20 amino acids found in the human body, and through extensive research has been found to be a potent and effective sleep aid. With a few key mechanisms by which it not only improves the quantity of sleep and quality of sleep but also can be directly tied to improved performance the next day, which is the true metric that we’re all after.
How Glycine Improves Sleep
Glycine enhances sleep quality primarily by helping decrease core body temperature during sleep onset. Glycine facilitates this process by increasing peripheral blood flow, which promotes heat loss from the body’s core. This thermoregulatory effect has been shown to aid in faster sleep onset and deeper, more restorative sleep.
In a pivotal study, researchers administered 3 grams of glycine to participants before bedtime and found significant improvements in subjective sleep quality and sleep maintenance.
Participants reported three primary benefits:
-
The subjects fell asleep faster.
-
Experienced fewer interruptions during the night.
-
Spent more time in non-rapid eye movement (NREM) sleep- a critical phase for physical recovery.
(Bannai & Kawai, 2012)
Glycine and Next-Day Performance
Beyond improving sleep, glycine has been shown to positively impact cognitive and physical performance the following day. In one study, participants who took glycine before bed reported reduced daytime sleepiness and improved subjective alertness during cognitive tasks.
(Takahashi et al., 2012)
This effect is thought to result from enhanced sleep architecture, particularly the restorative benefits of NREM sleep.
Physical performance also benefits from glycine supplementation. Athletes often rely on deep sleep for muscle recovery and glycogen replenishment—processes that are optimized during NREM sleep. By improving sleep quality, glycine ensures that these physiological processes occur efficiently, leading to better performance during training or competition.
This is a key factor when appraising sleep aids; there are plenty of pharmacological, herbal, and hormonal sleep aids that can induce sleep, lengthen quantity, and even improve quality, but do so at the cost of your performance the next day.
Glycine’s proven potent mixture of sleep-improving effects, mixed with its performance benefits the day after, makes it a staple ingredient in Spoken’s Sleep Builder formula.
Recommended Dosage and Safety
Most studies examining glycine’s effects on sleep use a dosage of 3 grams taken approximately 30 minutes before bedtime. This dosage is well-tolerated in healthy adults and has not been associated with significant side effects.
References
Bannai, M., & Kawai, N. (2012). New therapeutic strategy for amino acid medicine: Glycine improves the quality of sleep. Journal of Pharmacological Sciences, 118(2), 145–148.
https://pubmed.ncbi.nlm.nih.gov/22293292/
Inagawa, K., Otsuki, T., Nakanishi, H., et al. (2006). Supplemental glycine improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep and Biological Rhythms, 4(1), 75–77. ttps://www.researchgate.net/publication/230167843_Glycine_ingestion_improves_subjective_sleep_quality_in_human_volunteers_correlating_with_polysomnographic_changes
Takahashi, M., Miyashima, M., & Mishima, K. (2012). Glycine improves sleep and next-day performance in sleep-restricted healthy individuals. Frontiers in Neurology, 3, 61. https://pubmed.ncbi.nlm.nih.gov/22529837/
Glycine: The Sleep Building Block
Glycine: The Sleep Building Block
When most people think of amino acids, they immediately think of muscle building, with branch-chain amino acids and essential amino acids being at the forefront of muscle-building marketing for decades. However, amino acids are capable of way more than just packing on muscle.
Glycine is one of the 20 amino acids found in the human body, and through extensive research has been found to be a potent and effective sleep aid. With a few key mechanisms by which it not only improves the quantity of sleep and quality of sleep but also can be directly tied to improved performance the next day, which is the true metric that we’re all after.
How Glycine Improves Sleep
Glycine enhances sleep quality primarily by helping decrease core body temperature during sleep onset. Glycine facilitates this process by increasing peripheral blood flow, which promotes heat loss from the body’s core. This thermoregulatory effect has been shown to aid in faster sleep onset and deeper, more restorative sleep.
In a pivotal study, researchers administered 3 grams of glycine to participants before bedtime and found significant improvements in subjective sleep quality and sleep maintenance.
Participants reported three primary benefits:
The subjects fell asleep faster.
Experienced fewer interruptions during the night.
Spent more time in non-rapid eye movement (NREM) sleep- a critical phase for physical recovery.
(Bannai & Kawai, 2012)
Glycine and Next-Day Performance
Beyond improving sleep, glycine has been shown to positively impact cognitive and physical performance the following day. In one study, participants who took glycine before bed reported reduced daytime sleepiness and improved subjective alertness during cognitive tasks.
(Takahashi et al., 2012)
This effect is thought to result from enhanced sleep architecture, particularly the restorative benefits of NREM sleep.
Physical performance also benefits from glycine supplementation. Athletes often rely on deep sleep for muscle recovery and glycogen replenishment—processes that are optimized during NREM sleep. By improving sleep quality, glycine ensures that these physiological processes occur efficiently, leading to better performance during training or competition.
This is a key factor when appraising sleep aids; there are plenty of pharmacological, herbal, and hormonal sleep aids that can induce sleep, lengthen quantity, and even improve quality, but do so at the cost of your performance the next day.
Glycine’s proven potent mixture of sleep-improving effects, mixed with its performance benefits the day after, makes it a staple ingredient in Spoken’s Sleep Builder formula.
Recommended Dosage and Safety
Most studies examining glycine’s effects on sleep use a dosage of 3 grams taken approximately 30 minutes before bedtime. This dosage is well-tolerated in healthy adults and has not been associated with significant side effects.
References
Bannai, M., & Kawai, N. (2012). New therapeutic strategy for amino acid medicine: Glycine improves the quality of sleep. Journal of Pharmacological Sciences, 118(2), 145–148.
https://pubmed.ncbi.nlm.nih.gov/22293292/
Inagawa, K., Otsuki, T., Nakanishi, H., et al. (2006). Supplemental glycine improves subjective sleep quality in human volunteers, correlating with polysomnographic changes. Sleep and Biological Rhythms, 4(1), 75–77. ttps://www.researchgate.net/publication/230167843_Glycine_ingestion_improves_subjective_sleep_quality_in_human_volunteers_correlating_with_polysomnographic_changes
Takahashi, M., Miyashima, M., & Mishima, K. (2012). Glycine improves sleep and next-day performance in sleep-restricted healthy individuals. Frontiers in Neurology, 3, 61. https://pubmed.ncbi.nlm.nih.gov/22529837/