Supplement
Supports electrolyte balance, enzymatic activity, and metabolic signaling.[1328,1420,1439, etc.]
Superscript reference numbers link to the Sources bibliography.
Composite Rating
Blends evidence depth, community direction, safety friction, and completeness.
Evidence Intensity
100/100
High depth from human/RCT/meta counts
Community Direction
63
Positive Lean • confidence Moderate
Safety Friction
100/100
High signal from adverse/interaction markers
Data Completeness
100%
Studies 15 • mentions 9 • links 26
Not medical advice. This product is for educational and informational purposes only. It does not diagnose, treat, cure, or prevent any disease and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions regarding a medical condition.
FDA disclaimer: These statements have not been evaluated by the Food and Drug Administration. Dietary supplements are not intended to diagnose, treat, cure, or prevent any disease. Results may vary. Not intended for use by pregnant or nursing women, individuals under 18, or those with known medical conditions without physician consultation.
If you are experiencing a medical emergency, call 911 or your local emergency number immediately.
Goal alignment: Metabolic Health, Energy, Heart Health, Longevity.[58,227,355, etc.]
Dose guide: Human-study daily dose: 555 mg-1100 mg/day (higher-confidence extraction from PubMed abstracts)..[58,227,355, etc.]
Category
Mineral
Evidence Tier
HIGH
Daily Guide
Human-study daily dose: 555 mg-1100 mg/day (higher-confidence extraction from PubMed abstracts).
Clinical Depth
Humans: 205 • RCTs: 75 • Meta: 2
Cohort / Real-World
Cohort signals: 0
Safety Markers
Adverse signals: 40 • Interactions: 27
Freshness, trend, and study timeline for this item
Status
Trend
→ Stable evidence base
Depth
255 total studies · 2 recent
Timeline
Total indexed
255
Human studies
205
Randomized trials
75
Animal-only studies
63
In vitro / tissue
45
Safety adverse signals
40
Weighted direction score: 63 (Positive Lean)
High when >=2 human meta-analyses, or >=5 human RCTs with substantial human literature volume.
Total indexed
255
Human studies
205
Randomized trials
75
Animal-only studies
63
In vitro / tissue
45
Safety adverse signals
40
Interaction signals
27
Meta-analyses
2
Distribution of evidence by study design strength
Evidence Strength: High
Composite of study volume, RCTs, and meta-analyses
PMID 33872340 • 2021
Effect of dietary treatment and fluid intake on the prevention of recurrent calcium stones and changes in urine composition: A meta-analysis and systematic review.
PLoS One
Open PubMedPMID 11329115 • 1999 Nov
Meta-analysis of calcium bioavailability: a comparison of calcium citrate with calcium carbonate.
Am J Ther
Open PubMedPMID 35623880 • 2022 Jun
Urate-lowering effect of calcium supplementation: Analyses of a randomized controlled trial.
Clin Nutr ESPEN
Open PubMedPMID 35466449 • 2022 Jul
Calcium Citrate Versus Calcium Carbonate in the Management of Chronic Hypoparathyroidism: A Randomized, Double-Blind, Crossover Clinical Trial.
J Bone Miner Res
Open PubMedPMID 11444420 • 2001 Jun
Absorbability and cost effectiveness in calcium supplementation.
J Am Coll Nutr
Open PubMedPMID 18410225 • 2008 Aug
Randomized controlled trial of the effects of calcium with or without vitamin D on bone structure and bone-related chemistry in elderly women with vitamin D insufficiency.
J Bone Miner Res
Open PubMedPMID 18258639 • 2008 Feb
Calcium supplementation and bone mineral accretion in adolescent girls: an 18-mo randomized controlled trial with 2-y follow-up.
Am J Clin Nutr
Open PubMedPMID 10367025 • 1999
Absorption of calcium as the carbonate and citrate salts, with some observations on method.
Osteoporos Int
Open PubMedPMID 38892706 • 2024 Jun 5
Nutrition, Vitamin D, and Calcium in Elderly Patients before and after a Hip Fracture and Their Impact on the Musculoskeletal System: A Narrative Review.
Nutrients
Open PubMedPMID 17507729 • 2007 Jun
Calcium supplementation in clinical practice: a review of forms, doses, and indications.
Nutr Clin Pract
Open PubMedPMID 30390820 • 2018 Dec
Conventional Treatment of Hypoparathyroidism.
Endocrinol Metab Clin North Am
Open PubMedPMID 28457049 • 2017 Feb
Calcium and Calcium Salts.
J Assoc Physicians India
Open PubMedPMID 39275246 • 2024 Sep 2
Appropriateness of Ketoanalogues of Amino Acids, Calcium Citrate, and Inulin Supplementation for CKD Management: A RAND/UCLA Consensus.
Nutrients
Open PubMedPMID 30915494 • 2019 Aug
Hydroxycitrate: a potential new therapy for calcium urolithiasis.
Urolithiasis
Open PubMedPMID 31643038 • 2019 Sep
Calcium citrate: from biochemistry and physiology to clinical applications.
Rev Endocr Metab Disord
Open PubMedBenefit reports: 7
Adverse reports: 1
No-effect reports: 0
Mixed reports: 1
Unclear reports: 0
Signal confidence: 0.44
Benefits
Adverse
No Effect
Strong positive empirical sentiment with adequate confidence; boost recommendation priority.
Reddit evidence: 8 mentions (confidence 0.44) across Supplements, Biohackers.
Amazon signal: 0 products scanned (confidence 0.00).
GNC signal: 0 products scanned (confidence 0.00) [ERROR].
terminated
Use adverse/interactions PubMed signal counts for screening; perform clinician review before high-dose or multi-drug stack use.
Human-study daily dose signal: 555 mg-1100 mg/day (confidence HIGH).
Extracted from 9 dosing mentions across 3 PubMed studies (mg/day).
Imported legacy community score: 8.0/10 (heuristic mapping confidence 1.00).
Imported legacy monthly cost signal: ~$18.00.
Legacy community note: Highly regarded in nootropic communities for mental clarity and energy. Elderly users report significant cognitive improvement. Some younger users find it mildly stimulating. Popular in anti-aging protocols.
post • r/Supplements • unclear
Kidney pain from calcium citrate supplements? Adding it to my water and it causes intermittent stinging pain 48h after. I had the same thing with eggshells powder or bone powder. Anyone experienced this? Thanks
Open mentionpost • r/Supplements • unclear
Best calcium supplement for absorption other than calcium citrate? I have issues with slow mao-a activity and calcium supplements help me. I'm trying to figure out which calcium supplement is the best absorption with all these new products…
Open mentionpost • r/Biohackers • unclear
Is pure calcium citrate powder a good form of supplementation? I probably have a calcium defiency and I was browsing around products, but I've mostly found supplements with calcium carbonate (which has supposedly a low absorption rate) or …
Open mentionpost • r/Biohackers • unclear
Best calcium supplement for absorption other than calcium citrate? I have issues with slow mao-a activity and calcium supplements help me. I'm trying to figure out which calcium supplement is the best absorption with all these new products…
Open mentionpost • r/Supplements • mixed
Confirmed blood test high vitamin D So I’ve been taking 10-20,000 iu of vitamin D for years. I also sunbathe twice a week for about 15 minutes. I live in California. Even now in January, we have many sunny days with highs of 70 degrees. I’…
Open mentionpost • r/Biohackers • benefit
How best to get calcium? Will almonds do? How best to get calcium? Will almonds do? I would love to get calcium through food but I hate dairy. The problem is I drink no milk or tea or coffee. I very seldom eat cheese or butter. I don't lik…
Open mentionpost • r/Supplements • benefit
How best to get calcium? Will almonds do? I would love to get calcium through food but I hate dairy. The problem is I drink no milk or tea or coffee. I very seldom eat cheese or butter. I don't like yogurt. Nor do I care for sardines, salm…
Open mentioncomment • r/Supplements • unclear
If the same stinging kidney pain shows up every time you add any form of calcium (citrate, eggshell, bone powder) Bodies don't usually scream like that for no reason. Calcium can mess with kidneys if you're even slightly prone to stones or…
Open mentioncomment • r/Supplements • unclear
That's a good signal to pause rather than push through supplementing calcium. Calcium supplements, especially when taken without food or in concentrated liquid form, can increase urinary calcium temporarily. In some people that can irritat…
Open mentioncomment • r/Supplements • unclear
You should take your calcium with vitamin D3, K2 and magnesium. Avoid taking with iron, zinc and multivitamin complexes ( cause they have iron and zinc in them) Calcium Citrate: Doesn't need acid. You can take it on an empty or full stomac…
Open mentionamazon
Amazon search for Calcium Citrate
Rating: n/a | Reviews: n/a
Open productEvidence Sources
Community Sources
PUBMED • Humans + preclinical triage
Counts aggregated from automated literature sweep and tiering rules.
Outcome: Tier HIGH; humans 205, RCTs 75, meta-analyses 2.[1328,1420,1439, etc.]
Open sourcePUBMED • 2021 • Human evidence curation set
PMID 33872340 from PLoS One.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 1999 • Human evidence curation set
PMID 11329115 from Am J Ther.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2022 • Human evidence curation set
PMID 35623880 from Clin Nutr ESPEN.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2022 • Human evidence curation set
PMID 35466449 from J Bone Miner Res.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2001 • Human evidence curation set
PMID 11444420 from J Am Coll Nutr.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2008 • Human evidence curation set
PMID 18410225 from J Bone Miner Res.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2008 • Human evidence curation set
PMID 18258639 from Am J Clin Nutr.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 1999 • Human evidence curation set
PMID 10367025 from Osteoporos Int.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2024 • Human evidence curation set
PMID 38892706 from Nutrients.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2007 • Human evidence curation set
PMID 17507729 from Nutr Clin Pract.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2018 • Human evidence curation set
PMID 30390820 from Endocrinol Metab Clin North Am.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2017 • Human evidence curation set
PMID 28457049 from J Assoc Physicians India.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2024 • Human evidence curation set
PMID 39275246 from Nutrients.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2019 • Human evidence curation set
PMID 30915494 from Urolithiasis.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open sourcePUBMED • 2019 • Human evidence curation set
PMID 31643038 from Rev Endocr Metab Disord.
Outcome: See linked PubMed abstract for methods and outcomes.[1328,1420,1439, etc.]
Open source