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Head-to-head evidence comparison — which supplement is right for you?
Calcium vs Prenatal Multivitamin: Calcium has the stronger overall evidence (8 vs 7/10); they're alternatives for prenatal support — the best pick depends on your goals. Take the 60-second quiz for a pick tailored to your goals.
Calcium wins 2 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Likely helps
14 of 16 studies with measurable effects showed benefit.
Top outcomes
Verdict
Mostly mechanism / observational
Top outcomes
1000–1200mg daily (split doses)
Split doses with meals, 500mg with breakfast, 500mg with dinner
Calcium Citrate
1 serving daily as labelled. The verified folic acid evidence rests on 400-800 mcg daily started before conception
with-meals
A prenatal containing 400-800 mcg folic acid, started at least one month before conception
A separate calcium dose taken at the same time as the prenatal reduces absorption of the prenatal's iron.
Separate by 2+ hours — take the prenatal and any calcium supplement at different times of day.
6-24 months
12-36 months
Throughout pregnancy
Within days of starting
Requires pre-conception start
Across pregnancy
Across pregnancy
n/a
Effects of combined calcium and vitamin D supplementation on osteoporosis in postmenopausal women: a systematic review and meta-analysis of randomized controlled trials.
Food & Function (2020) · Meta analysis · n=12000
Combined calcium and vitamin D significantly improved lumbar spine BMD in postmenopausal women
Association Between Calcium or Vitamin D Supplementation and Fracture Incidence in Community-Dwelling Older Adults: A Systematic Review and Meta-analysis.
JAMA (2017) · Meta analysis · n=51145
33 trials involving 51,145 participants were analyzed
Vitamin D and Calcium for the Prevention of Fracture: A Systematic Review and Meta-analysis.
JAMA Network Open (2019) · Meta analysis · n=51419
Meta-analysis of 11 randomized clinical trials with 51,419 participants
Effects and safety of periconceptional oral folate supplementation for preventing birth defects.
Cochrane Database Syst Rev (2015) · Meta analysis
Neural tube defects: RR 0.31 (95% CI 0.17-0.58) across 5 studies, 6,708 births — HIGH quality evidence
Prevention of neural tube defects: results of the Medical Research Council Vitamin Study. MRC Vitamin Study Research Group.
Lancet (1991) · Rct · n=1817
27 neural tube defects total: 6 in folic acid arms vs 21 in non-folic-acid arms — 72% protective effect, RR 0.28 (95% CI 0.12-0.71)
Prevention of the first occurrence of neural-tube defects by periconceptional vitamin supplementation.
N Engl J Med (1992) · Rct · n=4753
The comparator was NOT placebo — it was a trace-element supplement (copper, manganese, zinc and a very low dose of vitamin C)
Based on meta-analysis of 59 RCTs showing 0.6-1.8% BMD increases. Requires vitamin D co-supplementation for optimal effect. Effectiveness plateaus beyond 1200mg daily.
AI-estimated from published studies. Interpret as directional guidance.
Calcium has a higher evidence score (8/10 vs 7/10) and wins in 2 of 3 categories.
For prenatal support, Prenatal Multivitamin has a higher relevance score (96 vs 82).
A separate calcium dose taken at the same time as the prenatal reduces absorption of the prenatal's iron. Separate by 2+ hours — take the prenatal and any calcium supplement at different times of day. Consult a healthcare provider for personalized advice.
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.
Folate is essential; inositol + CoQ10 are the best bets — but conception evidence is limited.
What’s safe while nursing, the truth about milk-supply herbs, and what to avoid (it passes into milk).
The right pick depends on your goals. Answer a few quick questions for a personalised recommendation — or dig into the full evidence on each.