Equipment Reference
Double Wood Supplements
Double Wood Glycine 1000mg
Double Wood Glycine 1,000mg review — 300 capsules for hitting the clinically studied 3g pre-bed sleep and core-cooling dose without unflavored powder tubs.
300 capsules — 3g pre-bed doses without buying collagen tubs
Double Wood Glycine is 1,000mg per capsule so a 3g sleep dose is three capsules — the amount used in human trials that lowered core temperature and improved subjective sleep. Third-party tested, 300-count, and cheaper per gram than most collagen powders if you only want the sleep amino acid.
Health Disclaimer
This content is for general informational and educational purposes only. It is not medical advice, diagnosis, or treatment. Consult a qualified healthcare provider before starting any supplement, peptide, or health protocol. Read our full health disclaimer.
Typical price: $16 – $24 USD / 300 capsules
How It Works
Glycine is one-third of collagen by weight and an inhibitory amino acid. Sleep RCTs typically use 3g, which magnesium glycinate alone does not reliably deliver. Taste is sweet if you open capsules; most people swallow them.
Core Temperature Drop
3g glycine before bed is associated with a small drop in core temperature — a physiological cue for sleep onset.
Inhibitory Neurotransmitter
Glycine acts in brainstem and spinal cord; effects are calming without next-day grogginess for most users.
Stack Companion
Pairs with magnesium (glycinate already contains some glycine) plus optional apigenin and theanine.
What You'll Experience
First Nights
Days 1–5Some notice easier sleep onset and cooler feet/hands; others notice nothing until week two.
Habit
Week 2+Keep if sleep continuity improved. Drop if you already get 10g+ glycine from collagen.
Benefits
Trial-Backed Sleep Dose
Moderate Evidence3g is the studied amount — easier to hit with capsules than guessing collagen scoops.
Low Cost
Anecdotal300 capsules is 100 nights at 3g.
Risks & Considerations
GI Upset
low riskLarge single doses can cause loose stool — split or take with a small snack.
Not a Sleep-Apnea Fix
medium riskDoes not treat airway obstruction.
Community Reviews
Synthesized consensus from Reddit, forums, and expert sources.
Glycine is a frequent ‘slept cooler’ report. Double Wood is a common Amazon pick for 1g capsules.
- ·3g is the number
- ·Sweet if opened
- ·Stack after magnesium
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Read guideLast updated: 2026-09-21 · Informational only. Not medical advice. Health disclaimer.