Can You Take Calcium and Vitamin A Together?

Dose or timing may matter

The short answer

High-dose vitamin A (retinol) may interfere with calcium metabolism by antagonizing vitamin D-mediated calcium absorption and promoting bone resorption, potentially reducing the bone-building benefits of calcium supplementation.

How to arrange timing

Avoid excessive vitamin A supplementation (>10,000 IU/day of retinol) when supplementing calcium for bone health.

Reference

Reference noted for this combination: Promislow JH et al. Retinol intake and bone mineral density in the elderly. J Bone Miner Res. 2002;17(8):1349-1358

Important context

Whether supplements suit you together also depends on dose, product formulation, health conditions, and medication use. Ask a doctor or pharmacist first if you take medication, are pregnant or breastfeeding, or have a chronic condition.