Glycine
Glycine
A simple amino acid that dramatically improves deep sleep quality by lowering core body temperature.
Glycine is a non-essential amino acid that plays a crucial role in sleep quality. Taking 3g before bed has been shown in multiple studies to improve deep sleep, reduce daytime fatigue, and enhance cognitive performance the next day. It works by lowering core body temperature, a key trigger for sleep onset.
Mechanisms of Action
Core Temperature Lowering
Drops body temperature to trigger deeper sleep
NMDA Modulation
Acts as a co-agonist at NMDA receptors
Collagen Support
Key building block for collagen production
Recommended Dose
3g before bed
Optimal Timing
- 30-60 minutes before bed
Can be taken without food
Best Form
Powder (dissolves easily, tastes sweet)
Alternatives: Capsules (need multiple for 3g dose)
Powder is most practical as capsules require 4-6 pills for 3g. Tastes naturally sweet, can be mixed in water or taken directly.
Duration
Minimum: 1 weeks
Optimal: 2 weeks
Cycling: Not required
Note: Take on empty stomach or with light snack before bed. 3g is the well-studied dose; higher doses are not more effective.
Personalized Dosage Calculator
Get a dosage recommendation tailored to your body weight, age, goals, and health profile.
Set up your health profile for personalized recommendations
Deeper Sleep
More time in restorative deep sleep stages
Less Daytime Fatigue
Feel more refreshed and alert the next day
Faster Sleep Onset
Fall asleep more easily
Sweet Taste
Powder has a naturally sweet taste
Glycine is a normal dietary amino acid; supplementation not well-studied in pregnancy
May be particularly beneficial for age-related sleep issues
Who Should NOT Take This
- Clozapine users (glycine may affect drug efficacy)
Drug Interactions
May reduce clozapine effectiveness
May have additive effects
Possible Side Effects
Tip: Take with small snack
Tip: Usually not problematic; may reduce over time
Warnings
- Very well tolerated
- One of the safest sleep supplements
- Effects may be noticed on first night
Magnesium
stacks-wellMagnesium for relaxation, glycine for deep sleep
Comprehensive sleep quality improvement
L-Theanine
complementaryBoth promote relaxation through different mechanisms
Enhanced pre-sleep relaxation and sleep quality
Apigenin
stacks-wellApigenin for onset, glycine for deep sleep
Comprehensive sleep support
L-Serine
complementaryL-serine converts to glycine
Enhanced neurotransmitter and collagen support
Taurine
complementaryBoth support sleep through different mechanisms
Comprehensive sleep quality improvement
Top studies from 40+ peer-reviewed papers
Soh J et al. • GeroScience (2024)
“This systematic-review examined the effects of Glycine.”
Key Findings:
- The nervous system demonstrated the most positive effects, including improved psychiatric symptoms from longer-term glycine administration in psychiatric populations.
- While longer-term glycine administration improved sleep in healthy populations, these studies had small sample sizes with a high risk of bias.
- Larger and long-term studies with more robust study designs in healthy populations to examine the effects of glycine administration on preventing, delaying or reversing the ageing process are warranted.© 2023.
Huang X et al. • PloS one (2024)
“Our results confirm the adverse effects of ICP on co-existing pregnancy complications, obstetric and neonatal outcomes.”
Key Findings:
- There was a significant association between ICP and odds of C-section (OR: 1.42, p <0.001), preeclampsia (OR: 2.64, p <0.001), NICU admission (OR: 2.1, p <0.001), and pre-term birth (OR: 2.64, p <0.001).
- ICP was not associated with postpartum hemmorhage (OR: 1.31, p = 0.13), small for gestational age (OR: 0.87, p = 0.07), stillbirth (OR: 1.49, p = 0.29).
- Our results confirm the adverse effects of ICP on co-existing pregnancy complications, obstetric and neonatal outcomes.
- ICP in associated with severe complications including increased rates of preeclampsia, emergency C-sections, preterm births, l gestational periods and higher rates of NICU admissions.
Zhu Z et al. • The American journal of clinical nutrition (2023)
“Increased glutamic acid, aspartic acid, and gamma-aminobutyric acid and decreased glycine in plasma are associated with adverse outcomes after ischemic stroke, suggesting that plasma amino acid neurotransmitters may be potential intervention targets for improving prognosis of ischemic stroke.”
Key Findings:
- Addition of the 4 plasma amino acid neurotransmitters to conventional risk factors significantly improved the risk reclassification, as evidenced by integrated discrimination improvement and net reclassification improvement (all P < 0.05).
- Increased glutamic acid, aspartic acid, and gamma-aminobutyric acid and decreased glycine in plasma are associated with adverse outcomes after ischemic stroke, suggesting that plasma amino acid neurotransmitters may be potential intervention targets for improving prognosis of ischemic stroke.
- The CATIS trial was registered at clinicaltrials.gov (registration number: NCT01840072; URL: ===https://clinicaltrials.gov/ct2/show/NCT01840072?cond=NCT01840072&draw=2&rank=1).
Morze J et al. • Diabetes care (2022)
“Several plasma and serum metabolites, including amino acids, lipids, and carbohydrates, are associated with type 2 diabetes risk.”
Key Findings:
- Several plasma and serum metabolites, including amino acids, lipids, and carbohydrates, are associated with type 2 diabetes risk.
- Published in Diabetes care (2022)
- Further research warranted to confirm findings
Błaszczuk A et al. • Nutrients (2022)
“This meta-analysis provides evidence that consuming flaxseed, soy and red clover can have a beneficial effect on lipids in postmenopausal women and suggest a favorable effect in preventing cardiovascular diseases.”
Key Findings:
- The effect of soy protein on the lipid profile showed a significant decrease in TC levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0048, LDL-C levels: WMD = -0.15; 95% CI: -0.25-0.05; p = 0.0067, as well as a significant increase in HDL-C levels: WMD = 0.05; 95% CI: 0.02-0.08; p = 0.0034.
- Changes in the lipid profile showed a significant reduction in TC levels after the use of red clover (WMD = -0.11; 95% CI: -0.18--0.04; p = 0.0017) and a significant increase in HDL-C levels (WMD = 0.04; 95% CI: 0.01 to 0.07; p = 0.0165).
- This meta-analysis provides evidence that consuming flaxseed, soy and red clover can have a beneficial effect on lipids in postmenopausal women and suggest a favorable effect in preventing cardiovascular diseases.
Study Type Distribution
Goals This Supplement Supports
Related Goals
This information is for educational purposes only and is not intended as medical advice. Always consult a qualified healthcare provider before starting any supplement.