Skip to main content

Can I take Vitamin C and Vitamin D together?

Drug interaction guide

There is no known negative interaction between Vitamin C (ascorbic acid) and Vitamin D (cholecalciferol). In fact, they are often taken together in multivitamin supplements.

Video picks for Drug interactions

Continue reading below

Why this happens

These vitamins use different pathways for absorption and metabolism. Vitamin C is water-soluble and Vitamin D is fat-soluble, meaning they do not compete for the same transport systems in the body.

It is safe to take these two vitamins together. For the best absorption of Vitamin D, it is recommended to take it with a meal that contains some fat (such as yoghurt, eggs, or avocado).

Continue reading below

Kidney stones (renal calculi)

High doses of vitamin C can increase the amount of oxalate in your urine, which significantly raises the risk of developing kidney stones, especially if you have had them before.

Hypercalcaemia (high blood calcium)

You must not take Vitamin D if you have high levels of calcium in your blood or urine, as it can cause calcium to build up in your body and damage your kidneys or heart.

G6PD deficiency

Very high doses of vitamin C can cause oxidative stress and lead to the breakdown of red blood cells (haemolysis) in individuals with G6PD deficiency.

High-fat meals

Vitamin D is fat-soluble. It is best absorbed when taken with a meal that contains some fat (such as eggs, avocado, nuts, or dairy). Taking it on an empty stomach may reduce its effectiveness.

Continue reading below

Taking 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.

Continue reading below

Article history

The information on this page is written and peer reviewed by qualified clinicians.

  • 25 Jan 2026 | Originally published
flu eligibility checker

Ask, share, connect.

Browse discussions, ask questions, and share experiences across hundreds of health topics.

symptom checker

Feeling unwell?

Assess your symptoms online for free

Sign up to the Patient newsletter

Your weekly dose of clear, trustworthy health advice - written to help you feel informed, confident and in control.

Please enter a valid email address

By subscribing you accept our Privacy Policy. You can unsubscribe at any time. We never sell your data.