Basics
The percentage on the label is not an upper limit
NRV, BfR and EFSA answer different questions. Amounts in mg and µg help you tell them apart.
Key points
- The percentage on a supplement compares its amount with the EU nutrient reference value for labelling (NRV). This fixed label reference is not your personal requirement or a limit.
- To judge an amount, look at milligrams (mg) or micrograms (µg). Compare these with the EFSA upper limit or the BfR proposed maximum.
- The same percentage can mean very different things: 300% zinc is 30 mg, above the EFSA upper limit of 25 mg. 300% vitamin B6 is 4.2 mg, well below 12 mg.
- If you take several products, add them together. For most nutrients, food counts too.
What the percentage means
The EU sets fixed labelling reference values for vitamins and minerals, called NRVs [1]. 100% zinc is 10 mg, 100% vitamin B6 is 1.4 mg, 100% vitamin D is 5 µg, and 100% magnesium is 375 mg. The percentage is the amount divided by the NRV, multiplied by 100. It says nothing about your personal requirement or when an amount becomes too high.
Three values, three questions
NRV: How does the amount compare with a fixed labelling reference? [1]
EFSA upper limit: How much can adults consume daily over the long term from all sources without an expected risk, according to current knowledge? [2]
BfR proposed maximum: How much should one food supplement contain per daily portion? This is guidance, not law. [3]
| Nutrient | NRV = 100% | BfR proposal per supplement | EFSA upper limit |
|---|---|---|---|
| Zinc | 10 mg | 6.5 mg | 25 mg |
| Vitamin B6 | 1.4 mg | 0.9 mg (since 2024) | 12 mg (since 2023) |
| Vitamin D | 5 µg | 20 µg | 100 µg |
| Magnesium | 375 mg | 250 mg | 250 mg, only from supplements and fortified foods |
The calculation
Two supplements both show 300%. Zinc: 300% of 10 mg = 30 mg. This exceeds the EFSA upper limit of 25 mg, even before food is counted. Vitamin B6: 300% of 1.4 mg = 4.2 mg. This is well below the EFSA upper limit of 12 mg.
Several products
A multivitamin with 10 µg vitamin D plus drops with 20 µg gives you 30 µg per day. This exceeds the BfR proposal for a single supplement but stays below the EFSA upper limit of 100 µg. Stoffradar adds these amounts in My supplements.
What does above the limit mean?
The EFSA upper limit concerns long-term intake. Going above it on one day does not automatically mean harm. The further and longer you exceed it, the more reason there is to consider a change [2].
What you can do
- Look at mg and µg, not the percentage.
- Add together all products you take daily, or let Stoffradar do it.
- If you take medication, are pregnant or have a medical condition, ask your healthcare practice or pharmacy.
Written by Marc · last reviewed on 25/10/2026
Sources
Does not replace medical advice.
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