Can You Take Cyanocobalamin and Vitamin C Together?

May affect absorption

The short answer

High-dose vitamin C (≥500 mg) can degrade cyanocobalamin in the gastrointestinal tract. The ascorbic acid reduces the cobalt center and may release cyanide, converting it to inactive analogs.

How to arrange timing

Space cyanocobalamin and high-dose vitamin C at least 2 hours apart, or use methylcobalamin sublingually.

Reference

Reference noted for this combination: Herbert V, Jacob E. Destruction of vitamin B12 by ascorbic acid. JAMA. 1974;230(2):241-242

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.