What is E333?
Calcium citrate — a simple calcium salt of citric acid, used as an acidity regulator and firming agent, and a common calcium source in fortified foods.
E333 (calcium citrate) is made by combining calcium with citric acid, producing a salt used as an acidity regulator, firming agent and calcium fortification ingredient. It holds Generally Recognized As Safe status in the US, and belongs to the well-reviewed citrate family. Goodnessly rates it Safe.
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Read the FAQ →
What is calcium citrate?
Calcium citrate is made by combining calcium with citric acid, the same acid found in citrus fruits. It's part of the well-reviewed citrate family alongside citric acid itself and other citrate salts. Beyond its role as an additive, calcium citrate is also a common calcium supplement, valued because it's easier for the body to absorb on an empty stomach than some other calcium compounds.
What's it used for?
- Acidity regulator in a range of processed foods
- Firming agent in canned and processed fruits and vegetables
- Calcium fortification in juices, cereals and plant-based milk alternatives
- Buffering agent to stabilise pH
Where you'll find 333 on the shelf
Often used specifically to boost the calcium content of fortified products.
Is calcium citrate safe? What the research says
Calcium citrate belongs to the well-reviewed citrate family, with a long, uncontroversial safety record.
| Region | Status | What this means |
|---|---|---|
| AU/NZ Australia & New Zealand (FSANZ) | Permitted | Permitted as an acidity regulator and firming agent with no specific quantity restriction in most categories. |
| EU European Union (EFSA) | Permitted | Listed as E333, approved for general food use. |
| US United States (FDA) | GRAS | Holds Generally Recognized As Safe status under 21 CFR 582, used in accordance with good manufacturing practice. |
Calcium citrate is also widely used as a calcium supplement outside its food-additive role, valued for being easier to absorb on an empty stomach than some other calcium compounds.
- No significant regulatory changes: calcium citrate's approval status has remained stable, reflecting its long, low-controversy safety record.
This section is checked periodically rather than continuously — if you're reading this well after the date above, it's worth confirming nothing has changed before citing it.
Who this matters to
- People with kidney disease, who may need to monitor calcium intake generally as advised by their doctor
- Otherwise, no population group has a specific safety-based reason to limit E333
Goodnessly rates E333 Safe. It's part of the well-reviewed citrate family, with a long, uncontroversial history as both a food additive and a calcium supplement.
How to spot it on a label
E333 is usually declared clearly. Look out for:
- Calcium citrate
- 333 or E333
- "Firming agent (333)" or "Acidity regulator (333)" in the ingredients list
Fortified juices, cereals and plant-based milks are the most common places to find it.
Related additives
Frequently asked questions
Is calcium citrate the same as citric acid?
Closely related but not identical. Calcium citrate is made by combining calcium with citric acid, producing a salt used both as an additive and as a calcium supplement.
Why is calcium citrate added to fortified foods?
It's a convenient, well-absorbed source of calcium. Unlike some calcium compounds, calcium citrate can be absorbed even on an empty stomach, making it a popular choice for fortifying juices, cereals and plant-based milk alternatives.
Does Goodnessly rate E333 as safe, caution, or avoid?
Goodnessly rates E333 (Calcium Citrate) as Safe. It's part of the well-reviewed citrate family, with a long, uncontroversial safety record as both a food additive and a calcium supplement.
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