Water-Soluble VitaminsLow Risk

Vitamin C

Vitamin C is a low-risk supplementwith an RDA of 90 mg and a safe upper limit (UL) of 2000 mg per day according to FDA standards. CNS lists a RDA of 100 mg with the same UL; MHLW lists a RDA of 100 mg with the same UL. It has 3 known interactions with other supplements including collagen, iron, quercetin. Use NutriAudit to check if your supplement stack keeps this ingredient within safe limits.

Quick take

Vitamin C sits in the Water-Soluble Vitamins category. This page consolidates 5 regional standards, and the limits vary enough that you should not treat one region's rule as universal.

It also has 3 known interactions, so the question is not just the label dose but whether the rest of your stack adds extra risk.

Safe Limits by Region

RegionOrganizationRDAUpper Limit (UL)Unit
πŸ‡ΊπŸ‡Έ United StatesFDA902000mg
πŸ‡ͺπŸ‡Ί EuropeEFSA902000mg
πŸ‡¦πŸ‡Ί AustraliaTGA902000mg
πŸ‡¨πŸ‡³ ChinaCNS1002000mg
πŸ‡―πŸ‡΅ JapanMHLW1002000mg

RDA = Recommended Daily Allowance (adequate intake for most adults). UL = Tolerable Upper Intake Level (maximum safe daily amount).

Known Interactions

Vitamin C + CollagenLow Risk

Vitamin C enhances collagen synthesis (positive interaction).

Taking vitamin C with collagen is beneficial.

Vitamin C + IronLow Risk

Vitamin C enhances iron absorption (positive interaction).

Taking together is beneficial.

Vitamin C + QuercetinLow Risk

Vitamin C enhances quercetin absorption (positive interaction).

Taking quercetin with vitamin C is beneficial.

How to use this page

First match your product label against the dose table above, then check whether the known interaction list includes anything in your current stack.

If you are taking multiple supplements, the safest approach is usually to audit the whole stack instead of judging a single bottle in isolation.

Frequently Asked Questions

How much Vitamin C is too much?

The safe upper limit (UL) for Vitamin C is 2000mg per day according to FDA. Exceeding this amount regularly may increase the risk of adverse effects.

What is the recommended daily dose of Vitamin C?

The RDA for Vitamin C is 90mg per day for most adults. This amount is sufficient to meet the needs of 97-98% of healthy individuals.

Does Vitamin C interact with other supplements?

Yes, Vitamin C has 3 known interactions with other supplements. Vitamin C enhances collagen synthesis (positive interaction).

Are you taking Vitamin C?

Check if your supplement stack keeps Vitamin C within safe limits.

Audit My Supplements

Disclaimer: NutriAudit is a decision-support tool designed to help you review your supplement stack for potential duplicate, conflicting, or excessive ingredients. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider before making changes to your supplement routine, especially if you are pregnant, nursing, taking medications, or have a medical condition.

Based on reference standards from FDA, EFSA, TGA, and MHLW.

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