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Head-to-head evidence comparison — which supplement is right for you?
Whey Protein wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
13 of 17 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
26 of 30 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both Magnesium and Whey Protein have evidence — compare verdict strength side-by-side.
200-350mg elemental magnesium daily
Evening for sleep/relaxation (glycinate), Morning for energy (malate), Anytime (citrate)
Depends on goal - see notes
20-40g per serving
Post-workout (within 2 hours), Morning, Between meals
Whey Protein Isolate
1-2 weeks
1-2 weeks
1 week
Immediate
4-8 weeks
24-48 hours post-workout
Immediate
Within hours of consumption
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
Hypertension (2025) · 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.
Comparative Efficacy of Different Protein Supplements on Muscle Mass, Strength, and Physical Indices of Sarcopenia among Community-Dwelling, Hospitalized or Institutionalized Older Adults Undergoing Resistance Training: A Network Meta-Analysis of Randomized Controlled Trials
Nutrients (2024) · Meta analysis · n=5272
Treatment effects for main outcomes were expressed as standard mean difference (SMD) with 95% confidence interval (CI).
Effects of Whey Protein, Leucine, and Vitamin D Supplementation in Patients with Sarcopenia: A Systematic Review and Meta-Analysis
Nutrients (2023) · Meta analysis · n=637
However, appendicular muscle mass significantly improved in the experimental group compared to the control group.
A systematic review, meta-analysis and meta-regression of the effect of protein supplementation on resistance training-induced gains in muscle mass and strength
British Journal of Sports Medicine (2018) · Meta analysis · n=1863
Protein supplementation increases muscle mass gains
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.
Based on multiple meta-analyses with >3000 participants. Effects require concurrent resistance training. Benefits plateau around 30-40g per serving. Isolate forms may reduce digestive issues.
AI-estimated from published studies. Interpret as directional guidance.
Whey Protein has a higher evidence score (9/10 vs 8.5/10) and wins in 2 of 3 categories.
For build strength & muscle, Whey Protein has a higher relevance score (95 vs 50).
No known interactions between Magnesium and Whey Protein have been documented in our database. However, always consult a healthcare provider before combining supplements.