Calcium (Microcrystalline Hydroxyapatite, MCHC)
Also known as: MCHC, microcrystalline hydroxyapatite concentrate, ossein hydroxyapatite complex, OHC, bone meal calcium, hydroxyapatite calcium
A whole-bone extract made from bovine bone that keeps the natural hydroxyapatite mineral matrix together with collagen and other bone proteins. It is popular in premium bone-support formulas as a food-like calcium source that also delivers phosphorus and trace minerals. Elemental calcium is roughly 24% by weight, so servings are large. Sourcing matters: buyers look for grass-fed, BSE-free origin and heavy-metal testing.
Research summary
Provides calcium and phosphate in the same crystal form found in bone, alongside collagen peptides; absorbed as calcium and phosphate ions after digestion of the matrix.
Dosage
Daily amounts, elemental (24% of the compound is the element).
| Lowest studied | Typical range | Highest studied | Upper limit |
|---|---|---|---|
| 200 mg | 250–700 mg | 800 mg | 2,000 mg |
NIH ODS — UL is 2,500 mg/day for adults 19–50 and 2,000 mg/day for adults 51+; the app uses the lower adult value (total intake from food plus supplements)
Doses are elemental calcium. MCHC is typically 22–26% calcium and about 10% phosphorus; 0.24 is a working midpoint — verify against the supplier's certificate of analysis. Ossein-hydroxyapatite trials reviewed by Castelo-Branco used about 3.3 g/day of complex, close to 700–800 mg of calcium. Because it is a whole-food matrix, it is usually taken with meals.
Source material: bovine bone (freeze-dried, low-temperature processed)
As supplied: ≈ 24% Ca, ≈ 10% P; includes collagen and bone proteins
Forms of Calcium
| Form | Typical dose | Element % | Formats | Price |
|---|---|---|---|---|
| Calcium (Microcrystalline Hydroxyapatite, MCHC) | 250–700 mg | 24% | Capsule, Powder, Tablet | high |
| Calcium Carbonate | 250–600 mg | 40% | Capsule, Powder, Tablet, Gummy, Liquid | low |
| Calcium Citrate | 200–500 mg | 21% | Capsule, Powder, Tablet, Gummy, Liquid | low |
| Calcium Citrate Malate | 250–500 mg | 23% | Capsule, Powder, Tablet, Liquid | mid |
Format suitability
- Capsule
- Powder
- Tablet
- Softgel
- Gummy
- Liquid
Bulky and mildly meaty in aroma; capsules and tablets dominate. 500 mg elemental needs about 2,100 mg of MCHC. Not suitable for vegan formulas.
Formulation notes
Separate from iron and thyroid hormone. Often paired with vitamin D3, K2, and magnesium. Contributes phosphorus, which should be counted in the label totals.
- Has an upper limit
- Possible Prop 65 warning
Sources
Related ingredients
Manganese Bisglycinate
MineralManganese chelated with glycine, about 15% elemental manganese in commercial grades, used in bone, joint, and antioxidant formulas where manganese serves as a cofactor for enzymes involved in cartilage and bone matrix formation.
Typical: 1–5 mg
Manganese Gluconate
MineralA water-soluble manganese salt of gluconic acid with about 11–12% elemental manganese, common in multivitamins and bone formulas as an inexpensive, mild-tasting source.
Typical: 1–5 mg
Vitamin D3 (Cholecalciferol)
VitaminThe form of vitamin D the body makes from sunlight and the most effective supplemental form for raising blood levels.
Typical: 1,000–2,000 IU
Fish Oil (EPA/DHA Concentrate)
Fatty acidFish oil concentrate is a refined marine oil enriched in the long-chain omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).
Typical: 500–2,000 mg
Collagen Peptides (Bovine, Type I/III)
ProteinEnzymatically hydrolyzed collagen from bovine hide or bone, delivering short peptides rich in glycine, proline, and hydroxyproline.
Typical: 2.5–15 g