Glycine
Amino acid for sleep quality and next-day alertness.
Mentioned by Matthew Walker
Overview
Glycine is a simple amino acid that acts as an inhibitory neurotransmitter. Research shows it can lower core body temperature and improve sleep quality, with better subjective alertness the next day.
What experts say
Matthew Walker
Sleep researcher, UC Berkeley
"Glycine can help lower core body temperature, which is important for sleep initiation. 3 grams before bed is a reasonable dose."
Our take
Underrated sleep supplement. 3g before bed is the standard dose. It's cheap, safe, and actually tastes slightly sweet. Good alternative if you find magnesium alone isn't enough.
Products
NOW Glycine Powder
NOW Foods · $
Pure powder form. 1lb container for easy dosing.
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