Kawai et al. (2007)
Sleep and Biological Rhythms
Participants
Healthy volunteers with mild sleep complaints
Dosage
3 g glycine before bed
Result: Improved sleep quality and less next-day fatigue. Shorter time to fall asleep, measured objectively.
Studied for falling asleep
L-Glycine
L-Glycine · An amino acid (glycine) involved in collagen synthesis and thermoregulation
An amino acid studied for sleep quality in clinical trials. Per sachet: 2000 mg.
2000 mgin 1 Corti-Glow sachet
Helps with
Long tossing and turning before sleepFeeling overheated in the eveningLight, broken sleepNext-morning fatigue
In plain language
What it does in your body
Glycine is the simplest amino acid, one of the building blocks of collagen.
It is also involved in thermoregulation, how the body manages its internal temperature.
It acts gently on the nervous system in the evening, without forcing you to sleep.
Natural source:
Glycine is an amino acid your body makes on its own, also found in gelatin, bone broth, meat and fish. A noticeable evening effect needs a concentrated dose, which is why we include a clean 2000 mg in the sachet.
Why l-glycine is in Corti-Glow
Why this ingredient specifically, not an alternative.
To fall asleep, your core temperature has to drop by about 1°C. Glycine supports exactly that.
In Kawai (2007), taking glycine before bed improved sleep quality and reduced next-day fatigue.
It works in synergy with the other evening ingredients in the sachet, a calm mind + a cooled body.
How it works on the body
Mechanism, step by step.
1Widens the peripheral vessels
Glycine gently dilates the blood vessels in the skin of the hands and feet. The body releases heat outward through them.
2Lowers core temperature
To fall asleep, the body's core has to cool by about 1°C. This heat release makes the transition to sleep more natural and faster.
3Calms the nervous system
Glycine acts gently on the brain in the evening, less tension at bedtime, without a “drugged” feeling.
4Supports a steadier rhythm
An easier drift-off in the evening also means less fatigue and a clearer head the next morning.
What to expect
Realistic timeframes, not promises.
The first evening · L-Glycine
An easier “switch-off”. A sense that the body relaxes faster.
The first evening
An easier “switch-off”. A sense that the body relaxes faster.
The first week
You fall asleep faster. Less tossing in bed.
2–3 weeks
Less morning fatigue. A steadier evening rhythm.
How it works with the other ingredients
7 ingredients. Each pair with a specific mechanism.
Not random supplements in one box. Every combination has a biological reason.
Combination
L-Glycine + Magnesium
+ Magnesium Bisglycinate · 670 mg
For sleep and muscle relaxation
Mechanism
Magnesium bisglycinate is actually magnesium bound to two glycine molecules, the same amino acid. So the two ingredients come from the same material: magnesium contributes to normal muscle function, while glycine is among the most-studied amino acids for evening use.
End benefit
A relaxed body and a smoother transition into sleep.
2 combinations · click to explore
This is why they aren't sold separately, one sachet, the full chain.
The research
Don't take our word for it, see what the science says.
PubMed
Inagawa et al. (2006)
Sleep and Biological Rhythms
Participants
19 healthy volunteers
Dosage
3 g glycine before bed
Result: Subjectively better sleep quality and less daytime fatigue after the nights with glycine.
Why this exact dose in Corti-Glow
2000 mg, specific, not random.
- →2000 mg is a meaningful evening dose in combination with the glycine from magnesium bisglycinate.
- →Chosen for synergy with the other evening ingredients, not as a standalone sleep aid.
- →Pure L-glycine, dissolves quickly in water and has a slightly sweet taste.
Dose comparison
in mgSee how our dose compares with what was used in clinical trials.
Corti-Glow, our dose
our dose, 2000 mg
2000 mg
Kawai 2007
3 g glycine before bed
3 mg
Inagawa 2006
3 g glycine before bed
3 mg
Corti-GlowClinical study
Frequently asked questions
About l-glycine.
Will it knock me out like a sleeping pill?+
No. Glycine is not a sedative and doesn't force you to “switch off”. It simply helps the body cool down and move into sleep more naturally. There's no grogginess or hangover feeling in the morning.
Why 2000 mg and not 3 g like in the studies?+
The Kawai studies use 3 g on its own. In Corti-Glow, glycine is 2000 mg because it works together with magnesium (which also carries glycine) and the other evening ingredients. The whole sachet is designed as a combination, not as separate doses.
Does it have a taste?+
Glycine is slightly sweet on its own, so it dissolves pleasantly in water and helps the taste of the sachet, with no added sugar.
Works well with
The other ingredients in Corti-Glow.
For sleep and muscle relaxation
Magnesium Bisglycinate
670 mgMagnesium contributes to normal nervous system and muscle function. The bisglycinate form is chosen as gentler on the stomach than the oxide.
See detailsFor cycle and sugar cravings
Myo-Inositol
2000 mgStudied in dozens of clinical trials in women — mostly for the cycle and insulin sensitivity. 2000 mg per sachet, the dose from the studies.
See detailsThis information is general and does not replace medical consultation. If you have a diagnosed condition, are pregnant, or are planning pregnancy, consult your doctor before supplements.