Both support sleep through different mechanisms
Glycine lowers core body temperature and supports inhibitory neurotransmission. Magnesium supports GABA and muscle relaxation.
Excellent combination for sleep quality.
Take both before bed
Both support sleep through different mechanisms. Excellent combination for sleep quality.
Take both before bed
This interaction is rated “Synergy” by Formulate. Glycine lowers core body temperature and supports inhibitory neurotransmission. Magnesium supports GABA and muscle relaxation.
Studies from our registry that mention glycine or magnesium. Each links to the primary source and the other Formulate pages citing it.
Mentions magnesium · 2018
Superiority of magnesium and vitamin B6 over magnesium alone on severe stress in healthy adults with low magnesemia
Pouteau et al. · PLOS ONE
Mg+B6 combination outperformed Mg alone for stress score reduction in adults with low baseline magnesium.
Mentions magnesium · 2018
The role of magnesium in neurological disorders
Kirkland AE, Sarlo GL, Holton KF · Nutrients
Reviews mechanisms and clinical evidence for magnesium's role in migraine prophylaxis, stress, anxiety, and depression — with strongest RCT support for migraine prevention at 400–600mg/day.
Mentions magnesium · 2016
Effects of magnesium supplementation on blood pressure: a meta-analysis of randomized double-blind placebo-controlled trials
Zhang X, Li Y, Del Gobbo LC, et al. · Hypertension
Meta-analysis of 34 trials (n=2,028) found magnesium supplementation at a median dose of 368mg/day for 3 months significantly reduced systolic BP by 2.00 mmHg and diastolic BP by 1.78 mmHg.
Mentions magnesium · 2016
Efficacy and Safety of MMFS-01, a Synapse Density Enhancer, for Treating Cognitive Impairment in Older Adults
Liu et al. · Journal of Alzheimer's Disease
Magnesium L-threonate (Magtein) improved cognitive ability in older adults with cognitive concerns over 12 weeks.
Mentions glycine · 2015
The sleep-promoting and hypothermic effects of glycine are mediated by NMDA receptors in the suprachiasmatic nucleus
Kawai N, Sakai N, Okuro M, et al. · Neuropsychopharmacology
Mechanistic study identifying how glycine at bedtime lowers core body temperature via NMDA receptor activation in the SCN — the proposed mechanism for its observed sleep-onset latency benefits.
Mentions magnesium · 2012
The effect of magnesium supplementation on primary insomnia in elderly: a double-blind placebo-controlled clinical trial
Abbasi B, Kimiagar M, Sadeghniiat K, et al. · Journal of Research in Medical Sciences
8-week RCT in elderly with insomnia: 500mg/day magnesium significantly improved subjective insomnia score, sleep efficiency, sleep onset latency, and serum melatonin concentration.
Protocol
Best Sleep Supplement Protocol 2026: Clinical Evidence Stack
Build a cheap, non-habit-forming sleep stack using magnesium glycinate, L-theanine, and glycine — three compounds with the strongest clinical trial support.
Guide
Magnesium Glycinate vs Citrate vs Oxide: Which Form Actually Absorbs?
Glycinate (80% absorbed) vs citrate (50%) vs oxide (4%) — with elemental-dose math, side effects, and picks for sleep, constipation, and cognition.
Roundup
Best Magnesium Supplements 2026, Ranked by Clinical Evidence
Learn which magnesium form actually matches your goal. We scored glycinate, threonate, and citrate on absorption, dose accuracy, and third-party testing.
Guide
8 Signs of Magnesium Deficiency – 2026 Guide
Muscle cramps, twitching eyelids, and poor sleep may signal low magnesium. Learn all 8 signs, why standard blood tests miss it, and how to fix it.
Other interactions to know
PPIs can cause hypomagnesemia
High calcium can impair magnesium absorption
Magnesium may enhance BP lowering effect
PPIs impair magnesium absorption
NSAIDs may reduce magnesium levels
Magnesium may reduce thyroid med absorption
Magnesium needed for vitamin D activation
Complementary sleep support
Check your full stack in the free interaction checker.
The free checker lets you add any combination of supplements and medications at once. The free web app goes further — every stack change surfaces interaction alerts automatically.
Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.
Last medically reviewed: