Reacted Cal-Mag by Ortho Molecular Products

If your Vitamin D, 25-Hydroxy is low-normal and your diet is light on dairy, leafy greens, or nuts, a calcium magnesium supplement is a practical way to cover the two minerals bones use most. It also fits people with nighttime calf cramps or frequent muscle tightness, and those on proton pump inhibitors for reflux who often run low on magnesium. If you’re tracking bone density with a DEXA scan (the X‑ray that measures bone strength), pair this with adequate vitamin D and protein for meaningful results.

Calcium is the structural mineral in bone, while magnesium helps convert vitamin D to its active form and keeps parathyroid hormone (the signal that pulls calcium from bone) in a healthy range. In muscle, calcium triggers contraction and magnesium allows relaxation, which is why getting both in balance can ease cramping. Phosphorus is the other half of hydroxyapatite, the crystal that hardens bone. Real-world fracture reduction is most consistent when calcium and magnesium are taken with vitamin D in those who are genuinely low.

Follow the label’s split dosing: 1–2 capsules three times daily with meals. Minerals absorb better in divided doses, and calcium uptake levels off if you take a large amount at once. If you also take iron or levothyroxine (thyroid medication), separate by at least 4 hours. Many people put one dose at dinner since magnesium can feel calming in the evening.

Antibiotics in the tetracycline or fluoroquinolone families bind minerals; separate by 6 hours. Bisphosphonates for osteoporosis also need separation by several hours. Thiazide diuretics raise blood calcium, so avoid extra calcium unless your clinician is monitoring. Loop diuretics increase magnesium loss, which can make this more useful. Check Magnesium, RBC (a red blood cell magnesium test) and PTH if cramps or bone turnover remain an issue.

Skip high-dose calcium if you have a history of high blood calcium, overactive parathyroid, or sarcoidosis, and avoid magnesium supplements in advanced kidney disease unless supervised. If you form kidney stones, take calcium with meals, not between, and discuss total intake with your clinician. Constipation from calcium or loose stools from magnesium are signs to adjust the dose or timing.