Medical disclaimer: SnoozeVerdict summarizes what people say about sleep supplements on Reddit. It is not medical advice, and nothing here is meant to diagnose, treat, cure, or prevent any disease. These statements have not been evaluated by the Food and Drug Administration. Talk to your doctor or pharmacist before starting a supplement, especially if you are pregnant, take medicines (including sleep or mood medicines), or have a medical condition. Poor sleep that lasts for months, loud snoring or gasping at night, or falling asleep during the day while driving or working needs a doctor, not a supplement. Full disclaimer.

Question · Deep sleep

Does glycine improve sleep quality?

Many say yes, going by Reddit owner reports: 20 of 22 rated comments from people who talk about deep or restful sleep describe a good experience with Glycine, and 0 describe a poor one. That is self-reported experience, not proof that it works, and results vary from person to person.

Glycine, Deep sleep	Owner comments
Rated comments in this context	22
Positive	20 (91%)
Negative	0 (0%)
Describe an unwanted effect	1
Context rating (small samples pulled to the average)	3.9

Glycine overall: 3.9 from 281 owner comments in Reddit sleep, insomnia and supplement communities, May 2026 to October 2026.

What the research says

Glycine is a simple amino acid; Japanese studies gave about 3 g before bed and measured subjective sleep quality.^[PubMed]
A 2012 study gave glycine to healthy volunteers whose sleep was restricted and measured daytime sleepiness and fatigue.^[PubMed]

Safety

Supplements can interact with medicines and are not reviewed by the FDA for safety before they are sold; tell your doctor or pharmacist about anything you take.^{[NIH Office of Dietary Supplements]}

Good experiences

4/5 CostDeeper sleep
“I have gone from waking every few hours to full nights of great sleep with this stack: 3g of glycine and 2 capsules of SleepElite about 30 minutes before sleep.”

owner comment via r/sleep · 2026-05-03 · 2 upvotes

4/5
“I have been taking a blend of glycine, magnesium glycinate, apigenin and a few others and have seen big improvements in my whoop sleep score, so look into that if you are seeking better supplementation.”

owner comment via r/sleep · 2026-10-04 · 5 upvotes

4/5 Deeper sleep
“I take glycine like 30 minutes before bed and it definitely helps with sleep quality.”

owner comment via r/Supplements · 2026-06-08 · 4 upvotes

How reports compare in other contexts

Context	Rated comments	Positive	Negative
Staying asleep	14	9	4
Falling asleep	11	8	2

More on Glycine

Talk to a doctor about new, severe or lasting symptoms, and to a pharmacist before combining supplements with medicines.