Take 30 to 60 minutes before lights-out
Pinned to before bed, the best window for Glycine.
Take 30 to 60 minutes before lights-out
Supports sleep onset; take ~30 minutes before bed. Best window is before bed, optional food. Educational only, not medical advice.
Glycine is a small amino acid the body uses to synthesize collagen, creatine, glutathione, and bile acids, and it acts as an inhibitory neurotransmitter in the brainstem and spinal cord. The studied sleep dose (3 g before bed) appears to work partly by triggering a slight drop in core body temperature, the same drop that precedes natural sleep onset.
3g of glycine ~30 min before bed has been studied for improving subjective sleep quality and reducing daytime fatigue.
30 minutes before bed, 3 g dissolved in water (it is naturally sweet). Empty stomach is fine, glycine absorbs quickly. Daily use is well-tolerated, no need to cycle. If you also use magnesium glycinate, the glycine in that compound contributes a small amount but not the full studied 3 g, take additional glycine on top if the sleep benefit is your goal.
| Window | Fit | Note |
|---|---|---|
| Morning | Poor | Calming effect works against the day |
| Midday | Okay | Fine if the preferred window is not possible |
| Evening, 1-2h before bed | Best | Aligns with winding down |
Tap each to see why.
Often paired in wind-down routines.
Take together
Plain glycine powder is the cheapest, most flexible, and easiest to dose, one teaspoon is roughly 3 g. Capsules work but you need 5 to 6 of them to hit the dose, expensive over time. Avoid 'glycine complex' blends that bury the dose under other ingredients.
| Form | Notes |
|---|---|
| powder | Flexible dose, ideal when scaling up gram-level intake. |
| capsule | Standard delivery, neutral taste. |
Who takes it: Adults with sleep-onset trouble, people whose minds race at bedtime, people who wake unrefreshed despite enough sleep, and people pairing it with a magnesium and L-theanine wind-down routine.
Yes, glycine is naturally sweet, easy to mix in water.
On the science
The principles behind this guidance, solubility, circadian timing, and spacing, are explained on our science page.
OptimalNourish is strictly educational. We do not recommend dosages, diagnose conditions, or suggest treatments. Always consult a qualified healthcare professional before changing your supplement routine.
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