Glycine’s Potential Role in Sleep Quality
There are many dimensions to a good night’s sleep. There is duration (how long you sleep for), latency (how long it takes you to go to sleep), and the feeling of wakefulness the next day. How rested do you feel after a good night’s sleep? And is there a way to feel good and alert, even when you had a bad night’s sleep?
Clinical studies have explored this question with glycine. Glycine is an amino acid and a building block to critical structures in the body. It also acts as a neurotransmitter, meaning that it sends messages between the brain and body.
Research shows that glycine can also act in the body to help lower nighttime core body temperature. Lowered core temperature has been associated with better sleep quality. Glycine’s unique role in the body makes it positioned to potentially support wakefulness, even after a bad night’s sleep.
A randomized, single-blinded placebo-controlled crossover trial (n=11) explored the potential efficacy of glycine on parameters related to sleep quality and daytime cognitive function in individuals with poor sleep quality prior to the study. The treatment group received 3 g of glycine before bed on two consecutive nights, repeated twice with a week in between.
Study metrics included self-reported questionnaires regarding sleep quality and daytime sleepiness. These were paired with laboratory analysis of sleep quality using polysomnography (PSG).
After data analysis, the authors report overall sleep efficiency (the ratio of sleep time compared to the whole time in bed) to be over 90% in the glycine group, a statistically significant value when compared with placebo. Statistically significant improvements in daytime sleepiness, sleep satisfaction, and sleep latency were reported in the glycine group when compared with placebo. Those in the treatment group also scored higher on cognitive tests related to alertness, as compared with placebo. Moreover, the subjective analysis correlates with PSG data collected, meaning that what the participants experienced lines up with how they feel.
A similar randomized double-blind crossover trial involved 3 g of glycine before bedtime in individuals experiencing poor quality of sleep. Participants in the treatment group reported significant improvements in “clear-headedness,” “liveliness and peppiness,” and “fatigue.” In addition, longer-term studies involving glycine administration have observed improvements in sleep quality and parameters related to alertness and cognition.
While the data are promising, more research is needed before conclusions can be made. Further studies in this realm should include more participants, more heterogeneous populations, and longer study durations. However, this preliminary study shows promise for future research regarding glycine’s potential to support sleep quality.
Glycine can be found in dietary sources including certain fish and legumes.
Clinical studies have explored this question with glycine. Glycine is an amino acid and a building block to critical structures in the body. It also acts as a neurotransmitter, meaning that it sends messages between the brain and body.
Research shows that glycine can also act in the body to help lower nighttime core body temperature. Lowered core temperature has been associated with better sleep quality. Glycine’s unique role in the body makes it positioned to potentially support wakefulness, even after a bad night’s sleep.
A randomized, single-blinded placebo-controlled crossover trial (n=11) explored the potential efficacy of glycine on parameters related to sleep quality and daytime cognitive function in individuals with poor sleep quality prior to the study. The treatment group received 3 g of glycine before bed on two consecutive nights, repeated twice with a week in between.
Study metrics included self-reported questionnaires regarding sleep quality and daytime sleepiness. These were paired with laboratory analysis of sleep quality using polysomnography (PSG).
After data analysis, the authors report overall sleep efficiency (the ratio of sleep time compared to the whole time in bed) to be over 90% in the glycine group, a statistically significant value when compared with placebo. Statistically significant improvements in daytime sleepiness, sleep satisfaction, and sleep latency were reported in the glycine group when compared with placebo. Those in the treatment group also scored higher on cognitive tests related to alertness, as compared with placebo. Moreover, the subjective analysis correlates with PSG data collected, meaning that what the participants experienced lines up with how they feel.
A similar randomized double-blind crossover trial involved 3 g of glycine before bedtime in individuals experiencing poor quality of sleep. Participants in the treatment group reported significant improvements in “clear-headedness,” “liveliness and peppiness,” and “fatigue.” In addition, longer-term studies involving glycine administration have observed improvements in sleep quality and parameters related to alertness and cognition.
While the data are promising, more research is needed before conclusions can be made. Further studies in this realm should include more participants, more heterogeneous populations, and longer study durations. However, this preliminary study shows promise for future research regarding glycine’s potential to support sleep quality.
Glycine can be found in dietary sources including certain fish and legumes.