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Head-to-head evidence comparison — which supplement is right for you?
Calcium vs Whey Protein: Whey Protein has the stronger overall evidence (9 vs 5.5/10); they're alternatives for build strength & muscle — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Whey Protein wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Too few graded studies
Top outcomes
Verdict
Likely helps
11 of 12 studies with measurable effects showed benefit.
Top outcomes
1000–1200mg daily (split doses) (no cited trial states the dose it used)
Split doses with meals, 500mg with breakfast, 500mg with dinner
Calcium Citrate
20-40g per serving
Before or after training, Morning, Between meals
Whey Protein Isolate
and 7 more not shown
and 1 more not shown
6-24 months
12-36 months
Throughout pregnancy
Within days of starting
4-8 weeks
24-48 hours post-workout
Immediate
Within hours of consumption
Use of calcium or calcium in combination with vitamin D supplementation to prevent fractures and bone loss in people aged 50 years and older: a meta-analysis
Lancet (2007) · Meta analysis · n=63897
29 randomised trials, 63,897 participants aged 50 or older, pooled with a random-effects model.
Role of calcium and/or vitamin D supplementation in preventing osteoporotic fracture in the elderly: a systematic review and meta-analysis
Indian J Med Res (2023) · Meta analysis
18 RCTs in adults over 60, comparing calcium, vitamin D or both against no treatment or placebo.
Calcium and vitamin D for increasing bone mineral density in premenopausal women
Cochrane Database Syst Rev (2023) · Systematic review · n=941
7 RCTs, 941 healthy premenopausal women: 138 randomised to calcium, 110 to vitamin D, 271 to both, 422 to placebo. Mean ages 18.1 to 42.1.
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
We finally included 78 RCTs (5272 participants) for analyses.
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
Three RCTs, 637 patients with sarcopenia, of combined whey protein, leucine and vitamin D.
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
49 RCTs, 1863 participants: protein supplementation increased 1RM strength (2.49 kg), fat-free mass (0.30 kg) and muscle fibre cross-sectional area during prolonged resistance training.
The points come from one dose-comparison RCT in 48 resistance-trained young men, who took 0, 10, 20 or 40 g of whey protein isolate straight after leg exercise, three hours after a high-protein breakfast (PMID 24257722). Over the next four hours myofibrillar muscle protein synthesis rose 49% above 0 g with 20 g and 56% with 40 g, and 10 g gave no added stimulation. The authors conclude 20 g is enough for the maximal response in about 80 kg men, and 40 g mainly raised amino acid oxidation and urea production. This is an acute measure of protein synthesis, not muscle growth over weeks of training, and the trial did not report tolerability, so no ceiling dose is set.
AI-estimated from published studies. Interpret as directional guidance.
Whey Protein has a higher evidence score (9/10 vs 5.5/10) and wins in 2 of 3 categories.
For build strength & muscle, Whey Protein has a higher relevance score (95 vs 45).
No documented interaction was found in the data searched. This does not establish that this exact combination is safe.
Hot flashes, bone, sleep, muscle — the basics that hold up vs the phytoestrogen hype.
When to take what, with or without food, and which supplements compete vs pair well.
The honest tier list — proven staples vs situational vs mostly marketing. The hub the other guides feed into.
On Ozempic/Wegovy/Mounjaro? What actually helps — muscle preservation, GI relief, nutrient gaps (no upsell).
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.