Timing Protocol

When to Take Glycine

What researchers say about when, how and with what to take glycine, and how strong the evidence is.

The verdict on Glycine overall

Leaning for

Glycine is worth taking.

6 sources: 3 positive, 3 partly

6 sources: 3 positive, 3 partly

Based on what researchers say in publicly available videos, not medical advice. Always consult your healthcare provider before starting, stopping, or changing any supplement.

Short answer

Before bed for sleep (Matthew Walker, on Huberman Lab). Glycine is taken in the morning in one longevity drink (Bryan Johnson). For collagen, timing is flexible; some evidence suggests taking it with vitamin C may help.

Full Protocol

Timing
Before bed for sleep (Matthew Walker, on Huberman Lab). Glycine is taken in the morning in one longevity drink (Bryan Johnson). For collagen, timing is flexible; some evidence suggests taking it with vitamin C may help.
Dosage
1-3g before bed for sleep (Matthew Walker, on Huberman Lab; Mark Hyman). Glycine is part of one daily longevity drink (Bryan Johnson). Up to 5g can come from collagen peptides for connective tissue.
Form
Glycine powder is the most common and cheapest form: it dissolves easily in water and tastes mildly sweet. Collagen peptides (hydrolyzed collagen) supply glycine with proline and hydroxyproline for connective tissue (Rhonda Patrick). Capsules exist, but powder makes dosing easier.
Notes
Glycine is very well tolerated, with no significant side effects at usual doses. It tastes sweet and mixes into water or tea. For glutathione, it pairs with NAC (N-acetyl cysteine), which supplies cysteine. Collagen peptides are about 20-25% glycine by weight and add other amino acids for connective tissue.

What the evidence says about timing

One verdict, worked out from every counted mention. One dot is one source: a researcher or a study. Tap a dot to see its receipt.

positive partly neutral negative Each researcher and each study counts once per claim, however often they come up.

Not enough evidence

Glycine taken before bed speeds sleep onset by lowering core body temperature.

2 sources: 2 partly. Fewer than 3 sources so far.

Researchers say

2 partly

Studies show

No study counted yet.

Show the receipts from 2 sources

  1. Dr Michael Breus, on Rangan Chatterjee's channel, at 1:28:37 Video · partly · Opinion

    “Also, the glycine is helps with temperature regulation.”

  2. Mark Hyman, on The Dr. Hyman Show, at 19:58 Video · partly · Opinion

    “it can really help support sleep quality. Can help lower your core body temperature, promotes deeper sleep, more restorative sleep for some people.”

Where the sources disagree

Built from every credited researcher and cited study on each claim.

Leaning for

Glycine is worth taking.

Supports it 3 sources
Partly 3 sources

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Full Glycine Report

Every claim with its verdict and receipts

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Glycine verdict