Issue No. 1 of Wellness Intelligence covered the ingredients that help us show up socially, mentally, and physically. This issue is about how we wind down. The global sleep market is worth billions, yet it is largely built on habit-forming pharmaceuticals, blunt sedatives, and products with questionable scientific foundations. At MAG Beverages, we are building something different: a sleep and calm formula grounded in peer-reviewed evidence, using ingredients with demonstrated mechanisms, measurable clinical outcomes, and clean safety profiles. Below we examine three ingredients two at the core of our formulation, and three additional candidates we recommend for consideration each backed by clinical research published in PubMed-indexed journals.

Ingredient No. 1

Magnesium Glycinate (Bisglycinate)

The Foundation Mineral

Magnesium is the fourth most abundant mineral in the human body and participates in over 300 enzymatic reactions yet surveys consistently show that a large proportion of Western adults fall short of recommended daily intake. Among the several supplemental forms available, magnesium glycinate (also called magnesium bisglycinate) is considered the most bioavailable and best-tolerated, making it particularly well-suited for functional beverage applications. Its sleep-relevant mechanism is clear: magnesium acts as a natural NMDA receptor antagonist and GABA agonist, directly modulating two of the brain's primary inhibitory and calming systems. It also supports melatonin synthesis and suppresses cortisol, giving it both a physiological and psychological mode of action.

The most rigorous clinical evidence to date on this specific form comes from a 2025 randomized, double-blind, placebo-controlled trial published in Nature and Science of Sleep. Researchers at Leibniz University Hannover enrolled 155 healthy adults aged 18–65 who reported poor sleep quality, assigning them to either 250 mg of elemental magnesium as bisglycinate or placebo daily for four weeks. Sleep quality was assessed at multiple time points using the validated Insomnia Severity Index (ISI), and statistical models adjusted for baseline ISI, age, sex, BMI, and occupation.

Clinical Evidence Schuster et al., 2025
Study Design
Randomized, double-blind, placebo-controlled trial. 155 adults with self-reported poor sleep. 4-week intervention. Nationwide home-based trial across Germany. Published in Nature and Science of Sleep (PMID: 40918053).
Primary Outcome
The magnesium bisglycinate group showed a significantly greater reduction in ISI scores compared to placebo from baseline to Week 4 (−3.9 vs. −2.3 points; p = 0.049). The effect size was small (Cohen's d = 0.2), indicating a modest but statistically significant benefit.
Key Finding
Exploratory analyses suggested notably greater improvements among participants reporting lower baseline dietary magnesium intake pointing to a high-responder subgroup: those already deficient in magnesium.
Safety Profile
Well-tolerated. Two placebo-group participants withdrew due to stomach pain; no significant adverse events reported in the magnesium bisglycinate group. The bisglycinate form is consistently cited as the most GI-friendly among magnesium supplements.
The bottom line: Magnesium glycinate addresses sleep at a biochemical level modulating GABA, cortisol, and melatonin simultaneously. For the significant proportion of adults with suboptimal magnesium intake, supplementation with the bisglycinate form offers a well-tolerated, evidence-supported path to improved sleep quality. Effect sizes are modest; the strongest responders appear to be those with existing dietary insufficiency.
Ingredient No. 2

L-Theanine

Falling Asleep Faster, Waking Up Better

Readers of Issue No. 1 will recognize L-theanine the amino acid from green tea for its role in daytime calm and cognitive focus. L-theanine earns its place in a sleep formula on related but distinct grounds. Its anxiolytic mechanism elevating GABA, serotonin, and alpha brain wave activity is precisely what the body needs to transition from wakefulness into restful sleep. Critically, it does this without sedating the user, which means it supports the body's natural transition to sleep rather than forcing unconsciousness the way pharmaceutical sleep aids do.

A comprehensive 2025 systematic review and meta-analysis published in Sleep Medicine Reviews the leading peer-reviewed journal dedicated to sleep science pooled data from 19 randomized controlled trials involving 897 participants, examining the full range of L-theanine's effects on sleep outcomes. Conducted by researchers at the University of Canberra and Deakin University, this is currently the most statistically robust analysis of L-theanine and sleep available in the scientific literature.

Clinical Evidence Bulman et al., 2025
Study Design
Systematic review and meta-analysis of 19 randomized controlled trials, 897 participants total. Published in Sleep Medicine Reviews (PMID: 40056718). Searches conducted across five major databases through September 2024.
Subjective Sleep Onset Latency
L-theanine significantly improved how quickly participants felt they fell asleep (SMD = 0.15, p = 0.04; 10 studies). Smaller but consistent effect across the literature.
Daytime Dysfunction & Sleep Quality
Significant improvements in subjective daytime dysfunction (SMD = 0.33, p < 0.001; 9 studies) and overall subjective sleep quality across the pooled trials.
Important Limitation
Objective sleep measures (actigraphy, polysomnography) did not show statistically significant improvement in the meta-analysis. Benefits were primarily reported on subjective self-assessment scales. Additionally, some trials included L-theanine in combination with other active ingredients.
The bottom line: Across 19 trials and 897 participants, L-theanine consistently improved subjective sleep onset and next-day function. At 200–400 mg, it is one of the most evidence-dense, safe, and versatile sleep support ingredients available. Objective polysomnographic data remains less conclusive, making self-reported quality the stronger signal in the current literature.
Ingredient No. 3

Glycine

The Amino Acid That Cools You Into Sleep

Glycine is the simplest amino acid in the human body and one of the most abundant yet its role as a sleep-promoting agent is still largely unknown to most consumers. Unlike sedatives that force the brain into unconsciousness, glycine works through a distinct physiological mechanism: it activates NMDA receptors in the brain's suprachiasmatic nucleus (the body's master circadian clock), triggering peripheral vasodilation and a measurable drop in core body temperature. This cooling effect is one of the key physiological triggers of natural sleep onset it is what your body does when it is ready to rest. Glycine also functions as an inhibitory neurotransmitter in the brainstem and spinal cord, promoting a state of calm that supports sleep continuity.

Two peer-reviewed studies from PubMed are particularly instructive. In a randomized, double-blinded crossover trial by Yamadera et al. (2007), 11 participants with chronic poor sleep ingested 3 g of glycine before bedtime, with sleep measured both subjectively and via polysomnography. In a separate randomized double-blind crossover study by Bannai et al. (2012) published in Frontiers in Neurology, researchers examined what happens when sleep is deliberately restricted by 25% and glycine (3 g) is given before bedtime. Together, these studies map both the objective sleep architecture effects and the real-world performance consequences of glycine supplementation. Note that both studies were conducted with support from Ajinomoto, a glycine manufacturer a standard disclosure in this ingredient category.

Clinical Evidence Yamadera et al., 2007 & Bannai et al., 2012
Yamadera 2007 Sleep Architecture
Randomized crossover trial. 11 adults with chronic sleep complaints. 3 g glycine before bedtime. Polysomnography confirmed shorter latency to sleep onset and to slow-wave sleep. Subjective sleep quality and daytime memory task performance also improved. Sleep architecture was preserved unlike benzodiazepines. Published in Sleep and Biological Rhythms.
Bannai 2012 Sleep Restriction Performance
Randomized crossover trial. Healthy volunteers with sleep restricted to 75% of normal for three consecutive days. 3 g glycine before bedtime significantly reduced next-day fatigue, sleepiness, and cognitive performance deficits compared to placebo. Published in Frontiers in Neurology (PMID: 22529837).
Formulation Advantages
Glycine is highly water-soluble, essentially tasteless, and well-tolerated at 3 g properties that make it exceptionally beverage-friendly. Its thermoregulatory mechanism is mechanistically distinct from every other ingredient on this list, giving it genuine synergistic potential in a multi-ingredient sleep formulation.
The bottom line: Glycine's sleep mechanism is biologically elegant and distinct cooling the body into sleep via the circadian clock rather than suppressing the nervous system. Human trial sizes are small, and replication in larger independent studies would strengthen the evidence base. At 3 g, it is one of the most cost-effective and beverage-compatible sleep ingredients available.