What is Glycine?
Glycine is the simplest amino acid — just two carbon atoms. Despite its simplicity, it plays several critical roles in the body:
- It is the primary building block of collagen (making up 1/3 of collagen)
- Acts as an inhibitory neurotransmitter in the brain
- Participates in creatine supplements, glutathione and hemoglobin synthesis
- The body can produce it, but often not in sufficient amounts
Glycine is a non-essential amino acid — the body can synthesize it, but recent research shows that most people's bodies do not produce it in optimal quantities.
Benefits of Glycine
Sleep Quality Improvement
Glycine's most exciting and well-studied benefit is its effect on sleep quality.
Studies by Bannai et al. (2012) and Inagawa et al. (2006) showed that 3g of glycine before bedtime:
- Reduces time to fall asleep
- Improves sleep depth and quality
- Reduces daytime fatigue and drowsiness
- Improves cognitive function the next day
- Increases the proportion of REM sleep
Mechanism: Glycine lowers core body temperature through peripheral vasodilation, which is a natural signal for sleep time (Kawai et al., 2015). It also modulates NMDA receptors in the brain.
Collagen Synthesis
Glycine makes up approximately one third of collagen's amino acid composition. Collagen is the body's most abundant protein, essential for:
- Skin elasticity and strength
- Joint cartilage health
- Tendon and ligament strength
- Bone structure
Supplementing with glycine supports collagen synthesis and can be especially beneficial for athletes who need fast recovery. Combine with collagen for the best effect.
Calming Neurotransmitter
Glycine acts as an inhibitory neurotransmitter in the brain — meaning it calms neural activity:
- Reduces anxiety and stress
- Supports calm mood
- Does not cause dependency or tolerance
- Especially effective in combination with magnesium
Blood Sugar Regulation
Studies have shown that glycine helps regulate blood sugar levels:
- Stimulates glucagon-like peptide-1 (GLP-1) release (Gannon et al., 2002)
- Improves insulin sensitivity
- Reduces HbA1c levels in type 2 diabetes patients
Anti-Inflammatory Effects
Glycine possesses significant anti-inflammatory properties:
- Inhibits inflammatory cytokines (TNF-alpha, IL-6) (Zhong et al., 2003)
- Supports liver health and normal metabolic processes
- Participates in glutathione (the body's main antioxidant) synthesis
Dosing
| Goal | Dose | When |
|---|---|---|
| Sleep quality | 3g | 30-60 min before bed |
| Collagen synthesis | 10-15g | Split throughout the day |
| Calming effect | 3-5g | As needed |
| Joint health | 5-10g | With vitamin C |
| General health | 3-5g | Any time |
Dosing tips:
- Sleep: Take 3g 30-60 minutes before bedtime
- Collagen: Split 10-15g into 2-3 doses daily
- Start with 3g and increase as needed
Forms of Glycine
Powder
- Most popular form
- Taste: Naturally sweet — pleasant taste without sweeteners
- Mix into water, tea or juice
- Most convenient for larger doses
- More affordable per gram
Capsules
- Convenient and precise dosing
- Easy to travel with
- Lower dose per capsule (typically 500mg-1g)
- Need to take many capsules for larger doses
Who Should Take It?
Especially beneficial for
- People with sleep issues — improves sleep quality naturally
- Athletes — for collagen synthesis and recovery support
- People with anxiety — calming effect without sedation
- Older adults — for joint and bone health
Also works well for
- People under stress
- People with digestive issues (supports stomach lining)
- Liver health support (glutathione synthesis)
Side Effects
Glycine is one of the safest supplements — even at high doses.
General safety:
- Studies have used up to 60g daily without serious side effects
- Mild nausea is possible at very high doses
- Rare mild digestive upset
Who should be cautious:
- Users of clozapine (schizophrenia medication) — glycine may affect drug action
- People already consuming large amounts of collagen (which contains glycine)
Our Recommendation
For Better Sleep
1. 3g glycine powder 30-60 min before bedtime
2. Mix into warm water or herbal tea
3. The sweet taste makes it pleasant to consume
4. Results often appear within the first week
For Collagen Synthesis and Joint Health
1. 10-15g glycine daily, split into 2-3 doses
2. Combine with vitamin C (50-100mg)
3. Athletes: take some before training with collagen
4. Use long-term for best results
For General Wellbeing
1. 3-5g daily
2. At any convenient time
3. Combine with magnesium for additional calming effect
Explore our glycine selection.
Summary
Glycine is a versatile and extremely safe amino acid that offers much more than meets the eye.
Key benefits:
- Sleep quality improvement (3g before bed)
- Collagen synthesis support (1/3 of collagen)
- Calming neurotransmitter without dependency risk
- Blood sugar regulation
- Anti-inflammatory effects
Key points:
- 3g before bed is the most researched dose
- Powder is naturally sweet — pleasant tasting
- Extremely safe even at high doses
- Sleep results often within the first week
- Combine with vitamin C and collagen for joint health
References
1. Bannai M, Kawai N, Ono K, Nakahara K, Murakami N. (2012). The effects of glycine on subjective daytime performance in partially sleep-restricted healthy volunteers. Frontiers in Neurology, 3, 61.
2. Inagawa K, Hiraoka T, Kohda T, Yamadera W, Takahashi M. (2006). Subjective effects of glycine ingestion before bedtime on sleep quality. Sleep and Biological Rhythms, 4(1), 75-77.
3. Kawai N, Sakai N, Okuro M, Karakawa S, Tsuneyoshi Y, Kawasaki N, Takeda T, Bannai M, Nishino S. (2015). The sleep-promoting and hypothermic effects of glycine are mediated by NMDA receptors in the suprachiasmatic nucleus. Neuropsychopharmacology, 40(6), 1405-1416.
4. Gannon MC, Nuttall JA, Nuttall FQ. (2002). The metabolic response to ingested glycine. American Journal of Clinical Nutrition, 76(6), 1302-1307.
5. Zhong Z, Wheeler MD, Li X, Froh M, Schemmer P, Yin M, Bunzendaul H, Bradford B, Lemasters JJ. (2003). L-glycine: a novel antiinflammatory, immunomodulatory, and cytoprotective agent. Current Opinion in Clinical Nutrition and Metabolic Care, 6(2), 229-240.
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