What is the relationship between glycine and sleep?

From the Guidelines

Glycine can be an effective supplement for improving sleep quality, and I recommend taking 3 grams of glycine about 30-60 minutes before bedtime for better sleep. This amino acid works by lowering core body temperature and helping you fall asleep faster while improving sleep quality. Glycine acts on NMDA receptors in the brain and may increase serotonin levels, which helps regulate sleep cycles. It also appears to reduce symptoms of daytime sleepiness and fatigue even when sleep duration isn't increased. Most people tolerate glycine well with minimal side effects, though some may experience mild gastrointestinal discomfort. You can find glycine as a powder or in capsule form at most health food stores or online retailers. For best results, use glycine consistently for at least a week to evaluate its effects on your sleep quality. If you're taking medications or have health conditions, consult with a healthcare provider before starting glycine supplementation, as it may interact with certain medications, particularly those affecting neurotransmitters 1.

Some key points to consider when using glycine for sleep:

• Start with a dose of 3 grams, 30-60 minutes before bedtime
• Use consistently for at least a week to evaluate effects
• May interact with certain medications, particularly those affecting neurotransmitters
• Generally well-tolerated with minimal side effects, but may cause mild gastrointestinal discomfort in some individuals
• Acts on NMDA receptors in the brain to regulate sleep cycles and increase serotonin levels
• May reduce symptoms of daytime sleepiness and fatigue, even when sleep duration isn't increased 1.

It's essential to note that while glycine may be beneficial for sleep, it's crucial to prioritize a healthy sleep environment and establish a consistent sleep schedule. Additionally, if you're experiencing persistent sleep difficulties, it's recommended to consult with a healthcare provider to rule out any underlying medical conditions that may be contributing to your sleep issues 1.

From the Research

Glycine and Sleep

• Glycine has been shown to have a sleep-promoting effect, with studies suggesting that it can improve sleep quality and reduce sleep latency 2.
• The mechanism of glycine's sleep-promoting effect is thought to involve the activation of NMDA receptors in the suprachiasmatic nucleus (SCN) 2.
• Glycine has also been shown to have a hypothermic effect, which may contribute to its sleep-promoting effects 2.
• In addition to its sleep-promoting effects, glycine has been shown to have anti-inflammatory, cytoprotective, and immune modulating properties 3.
• Glycine's role in neurotransmission is complex, and it has been shown to interact with other neurotransmitters such as GABA and glutamate 4, 5.

Glycine and Neurotransmission

• Glycine is an inhibitory neurotransmitter in the spinal cord and brain stem, and it has been shown to play a role in the regulation of sleep and arousal 3, 4.
• Glycine has also been shown to be involved in the regulation of REM sleep, with studies suggesting that impaired glycine transmission may contribute to the development of REM sleep behavior disorder 4.
• The structure, function, and regulation of glycine neurotransporters have been studied, and these transporters have been shown to play a critical role in the regulation of glycine's synaptic action 5.

Interactions with Other Compounds

• Glycine has been shown to interact with other compounds such as melatonin, which is also involved in the regulation of sleep and arousal 6.
• Melatonin and synthetic melatonergic agonists have been shown to have sleep-promoting effects, and they may interact with glycine to regulate sleep and arousal 6.