SupplementsGlycine
Sunday Natural
My take
“With L-Theanine and Magnesium Acetyl Taurate, the secret weapon for deep, restful sleep.”
NiklasUpdated 30 Mar 2026
Love it
- Lowers core body temperature — a key trigger for deep sleep
- Pure powder form allows precise dosing (3g recommended)
- Mildly sweet taste — easy to take dissolved in water
- Backed by solid research for sleep quality improvement
Fair warning
- Powder form less convenient than capsules for travel
- Needs 3g dose — quite a lot compared to other supplements
- Subtle effect — works best as part of a complete sleep stack
This may be an affiliate link. I only recommend what I genuinely use.
The longer story
Glycine
Glycine is an amino acid that plays a crucial role in sleep: it lowers your core body temperature, which is one of the primary triggers your body uses to initiate deep sleep.
Why I Recommend It
This is the third and final piece of my sleep stack. Glycine is the most underrated sleep supplement out there. While everyone focuses on melatonin (which I don't recommend for regular use), glycine works with your body's natural temperature regulation to deepen sleep.
The key insight: your body needs to drop 1-2°C in core temperature to enter deep sleep. Glycine accelerates this process naturally.
The Complete Sleep Stack
Take all three together, 30 minutes before bed:
- Magnesium Acetyl Taurate — calms the nervous system
- L-Theanine — reduces mental chatter
- Glycine (3g) — lowers core temperature for deeper sleep
Key Takeaways
- 3g before bed is the research-backed dose for sleep improvement
- Works by lowering core body temperature — a natural sleep mechanism
- Powder dissolves easily in water with a mildly sweet taste
- Sunday Natural sources pure, vegan-grade glycine
- Also supports collagen production and joint health as a bonus
Who It's For
Anyone who wants deeper, more restorative sleep without resorting to melatonin or sleeping pills. Especially effective for people who sleep in warm environments or have trouble reaching deep sleep phases.
