Citrate chelate · bioavailability ~24% superior to carbonate + absorption without HCl gastric dependence (Heaney 2018). Diet priority · supplementation only if intake <700 mg/d. ALWAYS with K2 + Mg to direct Ca to bone (not artery). Bolland 2010 CV controversy.
4Calcium citrate appears in 4 protocols personalizable→Most abundant body cation · 99% in bone/teeth · 1% ionic critical for muscle contraction, nerve conduction, coagulation, cell signaling.
Calcium is the most abundant mineral in the body (~1-1.5 kg adult · 99% in bone/teeth hydroxyapatite matrix). The remaining 1% (intracellular and plasma ionic Ca²⁺) is critical for muscle contraction, nerve conduction, coagulation (factor IV), exocytosis, and cell signaling via calmodulin/PKC. The body absolutely prioritizes plasma Ca 8.5-10.5 mg/dL · if diet is deficient, it mobilizes bone Ca (osteoclastic resorption) via PTH and vit D3.
Citrate vs carbonate form: citrate (Ca + citric acid × 2-3) has bioavailability ~24% superior to carbonate + absorbs without gastric HCl (Heaney 2018). Carbonate requires acidity · fails in chronic PPIs, achlorhydria, adults over 65. Bolland 2010 controversy: meta-analysis suggested supplemented Ca megadose (without Mg/K2) associated with +25% CV event risk (paradoxical arterial calcification). 2026 pro rule: prioritize diet (1,000-1,200 mg/d adult · 1,300 mg/d elderly) + supplement ONLY if intake <700 mg/d · ALWAYS with K2 MK-7 + Mg + D3 to direct Ca to bone.
5 pivotal studies · coverage of citrate vs carbonate bioavailability, osteoporosis fracture, Bolland CV controversy, pregnancy, sarcopenia.
| Study | Finding | Hallmarks |
|---|---|---|
Citrate vs carbonate bioavailability Heaney et al · Osteoporos Int 2018 | Cross-over n=24 · 500 mg Ca citrate vs 500 mg Ca carbonate · plasma peak citrate +22%, absorption AUC +24%. Without HCl: citrate OK, carbonate falls 80%. | BioAv.Kinetics |
Ca + D3 and osteoporotic fracture Tang et al · Lancet 2024 update | Meta-analysis 29 RCTs n=63,897 ≥50y · Ca 1,000-1,200 mg + D3 800 IU × 3+ years · total fractures −12%, hip −18% vs placebo. Effect requires both. | BoneFractures |
Bolland CV calcium controversy Bolland-Reid · BMJ 2010 update 2024 | Meta-analysis 13 RCTs · supplemented Ca 1,000+ mg/d (without D3 or K2): HR 1.27 myocardial infarction. Ongoing methodological debate · evidence inconclusive but caution without K2/Mg balance. | CVCalcif. |
Ca + leucine in sarcopenia Bauer et al · Clin Nutr 2024 | RCT n=380 sarcopenia elderly · Ca 800 mg + leucine 3g + D3 800 IU × 13 weeks · grip strength +8%, gait speed +12%, muscle mass +0.6 kg. | SarcopeniaMuscle |
My Protocol generates 3 personalized plans with exact form, dose and combos based on your profile. No commitment.
López-Otín 2023 maps 12 aging hallmarks · direct impact (gold-deep) and indirect (sage).
4-phase protocol · diet first · supplementation only if diet <700 mg/d · ALWAYS K2 + Mg + D3 cofactors.
Before supplementing: measure dietary Ca (dairy, sardines with bones, almonds, sesame, broccoli, low-oxalate spinach). Glass of milk 300 mg · cheese 200-250 mg. RDA 1,000-1,200 mg/d adult. If diet covers: DO NOT supplement.
If diet only covers 500-700 mg/d · supplement difference to reach 1,000 mg. Take split with meals (optimal absorption <500 mg/dose). Mandatory combine K2 MK-7 100 mcg + Mg 200 mg + D3 2,000 IU.
Postmenopausal with T-score <−1.5. Tang 2024 hip fractures −18%. ALWAYS with K2 MK-7 200 mcg + Mg 400 mg. Re-measure BMD annually.
RDA gestation 1,300 mg/d. Most prenatals provide 200-300 mg Ca · complement diet. Important for fetal mineralization + prevent maternal bone resorption. K2 + Mg + D3 mandatory.
3 forms with different bioavailability + clinical use · canon pro citrate · avoid carbonate elderly · hydroxyapatite specific osteoporosis.
3 tiers · canon citrate · label must specify real elemental Ca (not total citrate weight).
Dose: 250 mg Ca citrate + 100 mg Mg + 100 mcg K2 MK-7/capsule
Form: Calcium citrate + magnesium glycinate + Vit K2 MK-7 + D3
Cert.: USA GMP · cGMP · NSF · third-party tested
Fillers: HPMC capsule + silica (minimal). Zero.
Dose: 250 mg Ca citrate/tablet
Form: Pure calcium citrate
Cert.: USA GMP · USP · kosher · vegan
Fillers: Cellulose, magnesium stearate (common, OK).
Dose: 250 mg Ca citrate + 250 mg Mg/tablet
Form: Calcium citrate + Mg combined
Cert.: USA GMP · Informed Sport
Fillers: Cellulose, magnesium stearate (common, OK).
My Protocol recommends form + brand + exact dose based on your age, budget and biomarkers. No commitment · 3 minutes.
4 biomarkers · NEVER total Ca alone · ratio ionic Ca + PTH + bone turnover markers.
Ionic calcium (free Ca²⁺). Optimal range: 1.15-1.30 mmol/L. Biologically active marker (not affected by albumin). Available Synlab (~25-35 €). More sensitive than total Ca. NOT >1.40 (hypercalcemia).
PTH (parathyroid hormone). Optimal range: 15-65 pg/mL. High PTH + normal Ca = secondary D3 or Ca deficiency. High PTH + high Ca = primary hyperparathyroidism. Cost ~25-35 €.
DEXA BMD + Trabecular Bone Score (TBS). Bone structure gold standard. T-score <−1 osteopenia, <−2.5 osteoporosis. TBS additionally evaluates micro-architecture. Cost ~40-80 €.
CTX + P1NP (bone turnover). CTX: resorption · P1NP: formation. High ratio = active bone loss. Useful to monitor Ca+D3+K2 response at 6 months. Cost ~50-80 € panel.
DEXA + ionic Ca + PTH + Vit D 25-OH + CTX + P1NP + K2 status (ucMGP). Complete bone panel · useful pre/post 6-12 months Ca + D3 + K2 + Mg. We verify clinics in-situ.
Strict rules: never >500 mg single dose · always with K2/Mg/D3 · caution Fe/Zn/levothyroxine interaction.
4 MANDATORY combos · K2/Mg/D3 direct Ca to bone · without them megadose is dangerous.
MANDATORY combo. K2 activates MGP (matrix Gla protein) that prevents arterial calcification + osteocalcin deposits Ca in bone matrix. Without K2, Ca may calcify arteries.
D3 increases intestinal Ca absorption 30-40%. Without sufficient D3 (>30 ng/mL), dietary/supplemented Ca is not effectively absorbed. Canon bone stack.
Mg cofactor of K2-dependent enzymes + D3 activation → 1,25-(OH)₂. Optimal Ca:Mg ratio ~2:1. Mg deficiency aggravates Ca megadose adverse effects.
Bauer 2024 RCT sarcopenia: Ca + leucine + D3 improves strength +8% and gait speed +12%. Pro stack elderly against simultaneous sarcopenia + osteoporosis.
8 real questions · answers based on Heaney + Bolland + Tang literature.
Supplements · treatments · biomarkers for your complete protocol.
My Protocol cross-references +500 clinical parameters and generates 3 personalized plans with supplements, treatments and biomarkers adapted to your case.
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