Glutathione vs Glycine for skin & hair
Short answer: For skin & hair, more users report improvement with Glycine — 100% of 12 reports, versus 90% of 10 for Glutathione.
Glutathione has 967 meta-analyses and 1,685 randomized trials on PubMed; Glycine has 392 and 620.
Based on 156 reports about Glutathione and 695 about Glycine. Not medical advice.
| Glutathione Supplement | Glycine Supplement | |
|---|---|---|
| Users say it helped | 71%helped37 reports · medium confidence | 70%helped299 reports · high confidence |
| Verdict | Mostly positive | Mostly positive |
| Research | AResearch: Strong | AResearch: Strong |
| Meta-analyses / RCTs | 967 / 1,685 | 392 / 620 |
| Mainly used for | ||
| Sleep % reporting improvement | 100% (2) | 87% (255) |
| Anxiety % reporting improvement | — | 78% (60) |
| Mood % reporting improvement | — | 87% (39) |
| Energy % reporting improvement | 100% (7) | 94% (17) |
| Skin & hair % reporting improvement | 90% (10) | 100% (12) |
| Common side effects | injection site, insomnia, stomach issues, weakness | vivid dreams, drowsiness, fatigue, brain fog |
| Typical dose reported | 500 mg | 2 g / daily |
GlutathioneFull Glutathione profile →
Latest review conclusion
IV glutathione is contraindicated due to lack of efficacy and side effects. It may work more as an antioxidant in melasma.
Int J Dermatol, 2025 ↗What a user said
“IM 600mg 2x week. My head is clear, my energy is so much better and my skin is glowing!”
GlycineFull Glycine profile →
Latest review conclusion
In studies using high-throughput metabolomics, several blood amino acids appear to be consistently associated with the risk of developing type 2 diabetes.
Diabetes Care, 2016 ↗What a user said
“2 grams with 200mg magnesium before bed gives me crazy good sleep. Crazy vivid dreams.”
Related comparisons
Percentages come from first-hand user reports and are not clinical outcomes. Talk to a doctor before starting, stopping or combining anything. How we rate