Can I take Magnesium and Vitamin d together?
Drug interaction guide
Originally published 25 Jan 2026
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Magnesium and Vitamin D work together in a positive way. Magnesium helps your body activate Vitamin D so it can do its job, and Vitamin D helps your body absorb magnesium more effectively. Taking them together is generally beneficial rather than harmful.
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Why this happens
This is a 'synergistic' interaction. Magnesium is a necessary 'co-factor' for the enzymes that convert Vitamin D into its active form in the blood. Without enough magnesium, Vitamin D may remain stored and inactive. Conversely, Vitamin D can slightly increase how much magnesium your intestines absorb.
What you should do
Back to contentsIt is usually fine and often recommended to take these together. However, if you have kidney disease or are taking high-dose supplements, you should speak to your doctor or pharmacist first to ensure your dosages are appropriate for your needs.
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Using other medicines
Back to contentsTaking multiple medicines? Our Medicines Interaction Checker helps you check whether your prescriptions, over-the-counter medicines, and supplements are safe to take together. Simply search for your medicines to see potential interactions and what to do about them.
Disclaimer
This information is for general educational purposes only and should not be relied upon as a substitute for professional medical advice. Always consult your GP, pharmacist, or another qualified healthcare professional before making decisions about your medications. Individual circumstances may vary, and only a healthcare professional who knows your medical history can provide personalised guidance.
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Article history
The information on this page is written and peer reviewed by qualified clinicians.
25 Jan 2026 | Originally published

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