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Head-to-head evidence comparison — which supplement is right for you?
Magnesium wins 1 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Mostly mechanism / observational
2 of 2 studies with measurable effects showed benefit.
Top outcomes
Verdict
Probably helps
9 of 13 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both GABA and Magnesium have evidence — compare verdict strength side-by-side.
250-750mg
30-60 minutes before desired effect, Before bed for sleep, Before stressful events for anxiety
Capsules or powder
200-350mg elemental magnesium daily
Evening for sleep/relaxation (glycinate), Morning for energy (malate), Anytime (citrate)
Depends on goal - see notes
30-60 minutes
30-60 minutes
30-60 minutes
1-2 weeks
1-2 weeks
1 week
Immediate
Herbal Remedies and Their Possible Effect on the GABAergic System and Sleep
Nutrients (2021) · Systematic review
Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter that plays a major role in controlling different vigilance states.
Effect of Probiotics on the Symptomatology of Autism Spectrum Disorder and/or Attention Deficit/Hyperactivity Disorder in Children and Adolescents: Pilot Study
Research on child and adolescent psychopathology (2025) · Rct · n=80
A better comfort score (quality of life) was shown in children with ASD (probiotic: p = 0.010, Cohen's d = 0.722; placebo: p = 0.099, Cohen's d = 0.456).
GABA Supplementation, Increased Heart-Rate Variability, Emotional Response, Sleep Efficiency and Reduced Depression in Sedentary Overweight Women Undergoing Physical Exercise: Placebo-Controlled, Randomized Clinical Trial
Journal of dietary supplements (2024) · Rct · n=90
Moreover, an improved emotional response was observed, characterized by diminished negative affect.
Magnesium supplementation in pregnancy
The Cochrane database of systematic reviews (2014) · Meta analysis · n=9090
Women receiving magnesium were significantly less likely to require hospitalisation during pregnancy (RR 0.65, 95% CI 0.48 to 0.86; three trials, 1158 women).Of the 10 trials included in the review, only two were judged to be of high quality overall.
Magnesium Supplementation and Blood Pressure: A Systematic Review and Meta-Analysis
Nutrients (2024) · Meta analysis · n=2709
38 RCTs with 2709 participants analyzed
Magnesium and Potassium Supplementation for Systolic Blood Pressure Reduction in the General Normotensive Population: A Systematic Review and Subgroup Meta-Analysis for Optimal Dosage and Treatment Length
Nutrients (2024) · Meta analysis
Both supplements demonstrated greater reductions in SBP for the general population at lower dosages and longer treatment durations.
Limited direct GABA supplementation studies. Most evidence comes from GABA receptor agonist research showing somnolence as primary effect (RR 4.56). Effectiveness estimates are conservative given sparse direct supplementation data and questionable oral bioavailability of GABA across blood-brain barrier.
Based on meta-analysis of 38 RCTs with 2709 participants showing -7.68 mmHg reduction in hypertensive individuals. Effects are greatest in those with hypomagnesemia. Limited evidence in normotensive populations.
AI-estimated from published studies. Interpret as directional guidance.
Magnesium has a higher evidence score (8.5/10 vs 8.5/10) and wins in 1 of 3 categories.
For improve deep sleep quality, Magnesium has a higher relevance score (90 vs 62).
No known interactions between GABA and Magnesium have been documented in our database. However, always consult a healthcare provider before combining supplements.