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Head-to-head evidence comparison — which supplement is right for you?
Magnesium wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
5 of 5 studies with measurable effects showed benefit.
Top outcomes
Verdict
Probably helps
9 of 13 studies with measurable effects showed benefit.
Top outcomes
300-600mg daily
Morning for cognitive enhancement, 30-60 min before workout for performance
Alpha-GPC 50% powder or capsules
200-350mg elemental magnesium daily
Evening for sleep/relaxation (glycinate), Morning for energy (malate), Anytime (citrate)
Depends on goal - see notes
1-2 hours
2-4 weeks
Acute
Same day
1-2 weeks
1-2 weeks
1 week
Immediate
L-Alpha-Glycerylphosphorylcholine (L-α-GPC): A Comprehensive Review of Its Preparation Techniques and Versatile Biological Effects
Journal of food science (2025) · Systematic review
Due to its high choline content (41% by weight) and ability to cross the blood-brain barrier, GPC is considered one of the most utilized sources of choline.
Activity of Choline Alphoscerate on Adult-Onset Cognitive Dysfunctions: A Systematic Review and Meta-Analysis
Journal of Alzheimer's disease : JAD (2023) · Meta analysis · n=1326
We found significant effects of α-GPC in combination with donepezil on cognition [4 RCTs, mean difference (MD):1.72, 95% confidence interval (CI): 0.20 to 3.25], functional outcomes [3 RCTs, MD:0.79, 95% CI: 0.34 to 1.23], and behavioral outcomes [4 RCTs; MD: -7.61, 95% CI: -10.31 to -4.91].
Revisiting choline alphoscerate profile: a new, perspective, role in dementia?
The International journal of neuroscience (2013) · Systematic review
Choline alphoscerate (alpha-glyceryl-phosphorylcholine, alpha-GPC) is a semisynthetic derivative of phosphatidylcholine with central parasympathomimetic action.
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.
Based on RCTs showing cognitive improvements in healthy adults and dementia patients. Effect sizes were modest and some studies used combination therapy. Higher doses associated with increased headache risk.
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 2 of 3 categories.
For sharpen focus, Alpha-GPC has a higher relevance score (80 vs 70).
No known interactions between Alpha-GPC and Magnesium have been documented in our database. However, always consult a healthcare provider before combining supplements.