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vitamin b12 and vitamin c

High-dose vitamin C may reduce B12 absorption

What's happening

Very high doses of vitamin C (>1000mg) taken simultaneously may reduce B12 absorption.

Recommendation

Separate high-dose vitamin C from B12 supplements.

Timing

Separate by 2+ hours if taking high-dose vitamin C

Sources

  • — Journal of the American Dietetic Association

Frequently Asked Questions

Can I take vitamin b12 and vitamin c together?

High-dose vitamin C may reduce B12 absorption. Separate high-dose vitamin C from B12 supplements.

How should I time vitamin b12 and vitamin c?

Separate by 2+ hours if taking high-dose vitamin C

Is this interaction dangerous?

This interaction is rated “Caution” by Formulate. Very high doses of vitamin C (>1000mg) taken simultaneously may reduce B12 absorption.

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Medical disclaimer. This page is for educational purposes only and does not replace advice from a qualified healthcare provider.