Collagen vs Glycine for skin & hair
Short answer: For skin & hair, users rate them about the same: 96% report improvement with Collagen (71 reports) and 100% with Glycine (12 reports).
Collagen has 9 meta-analyses and 22 randomized trials on PubMed; Glycine has 392 and 620.
Based on 292 reports about Collagen and 695 about Glycine. Not medical advice.
| Collagen Supplement | Glycine Supplement | |
|---|---|---|
| Users say it helped | 56%helped120 reports · high confidence | 70%helped299 reports · high confidence |
| Verdict | Mixed | Mostly positive |
| Research | AResearch: Strong | AResearch: Strong |
| Meta-analyses / RCTs | 9 / 22 | 392 / 620 |
| Mainly used for | ||
| Sleep % reporting improvement | 100% (8) | 87% (255) |
| Skin & hair % reporting improvement | 96% (71) | 100% (12) |
| Anxiety % reporting improvement | — | 78% (60) |
| Recovery % reporting improvement | 94% (47) | 100% (9) |
| Mood % reporting improvement | 50% (2) | 87% (39) |
| Common side effects | fatigue, insomnia, drowsiness, histamine episode | vivid dreams, drowsiness, fatigue, brain fog |
| Typical dose reported | 7 g / daily | 2 g / daily |
The findings of improved hydration and elasticity were also confirmed in the subgroup meta-analysis. Based on results, ingestion of hydrolyzed collagen for 90 days is effective in reducing skin aging, as it reduces wrinkles and improves skin elasticity and hydration.
Int J Dermatol, 2021 ↗“Within hours of consumption my consistent upper back pain is literally gone, but along with it comes dizziness and a feeling of aloofness.”
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 ↗“2 grams with 200mg magnesium before bed gives me crazy good sleep. Crazy vivid dreams.”
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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