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Longevity Atlas
TargetedSleep, stressVegan form available

Glycine

A cheap amino acid that improved sleep quality and next-day alertness in small trials; as GlyNAC it moved ageing markers too.

2/5Estimated monthly cost: ≈ 4 €
Dose

3 g powder at bedtime; GlyNAC: 1.2 g/kg/day split evenly (trial dose only).

Timing

30–60 minutes before bed.

⚠ Cautions

Sweet-tasting, well tolerated; check with a doctor on clozapine.

What it is

An inhibitory neurotransmitter and building block of glutathione (the main cellular antioxidant); modern diets (little cartilage, skin, bone broth) lack it.

What the evidence shows

3 g before bed: faster sleep onset, deeper sleep and less daytime sleepiness in two small Japanese RCTs. GlyNAC (glycine + NAC) over 16 weeks improved oxidative stress, insulin resistance and gait speed in older adults (n=24).

Goals

SleepHealthy years

Sources

  1. Yamadera W et al. Glycine ingestion improves subjective sleep quality. Sleep Biol Rhythms (2007) ↗
  2. Kumar P et al. GlyNAC supplementation in older adults – RCT. J Gerontol A (2023) ↗

Last reviewed: 6 September 2026

This site is educational and does not replace medical advice. Start any supplement or drug only after consulting a doctor or pharmacist.