What is E552?
Calcium silicate — an anti-caking agent that stops powdery ingredients like salt and icing sugar from clumping together in humid conditions.
E552 (calcium silicate) is a fine white powder made from calcium and silica, used as an anti-caking agent. It's added in small amounts to powdered and granulated foods to absorb moisture and keep the product free-flowing rather than clumping together. Goodnessly rates it Safe.
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Read the FAQ →
What is calcium silicate?
Calcium silicate is a fine, chalky white powder made by combining calcium compounds with silica. Its main job is absorbing excess moisture: added in tiny amounts to powdered or granulated foods, it prevents individual particles from sticking together, which is why table salt and powdered products stay free-flowing even in humid conditions rather than forming hard clumps.
What's it used for?
- Anti-caking agent in table salt
- Powdered sugar and icing sugar
- Spice blends and seasoning mixes
- Powdered dairy and coffee products
Where you'll find 552 on the shelf
Anywhere a powdered product needs to stay free-flowing.
Is calcium silicate safe? What the research says
Calcium silicate is used in very small amounts as an anti-caking agent, with a clean regulatory record.
| Region | Status | What this means |
|---|---|---|
| AU/NZ Australia & New Zealand (FSANZ) | Permitted | Permitted as an anti-caking agent with no specific quantity restriction in most categories. |
| EU European Union (EFSA) | Permitted, no ADI | Listed as E552, with no numerical Acceptable Daily Intake needed. |
| US United States (FDA) | GRAS | Holds Generally Recognized As Safe status for use as an anti-caking agent. |
Calcium silicate is used at very low levels, typically well under 2% of the finished product, since only a small amount is needed to achieve its moisture-absorbing effect.
- No significant regulatory changes: calcium silicate'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
- No population group has a specific safety-based reason to limit E552 at typical food-additive levels
Goodnessly rates E552 Safe. It's used at very low levels, and holds a clean, long-standing regulatory record.
How to spot it on a label
E552 is usually declared clearly. Look out for:
- Calcium silicate
- 552 or E552
- "Anti-caking agent (552)" in the ingredients list
Table salt and icing sugar are the most common places to find it.
Related additives
Frequently asked questions
Why does table salt sometimes contain calcium silicate?
Salt readily absorbs moisture from the air, which can cause it to clump. Calcium silicate is added in tiny amounts to absorb that moisture instead, keeping the salt free-flowing and easy to pour, especially in humid climates.
How much calcium silicate is actually in food?
Very little. It's typically used at well under 2% of the finished product, since only a small amount is needed to achieve its anti-caking effect.
Does Goodnessly rate E552 as safe, caution, or avoid?
Goodnessly rates E552 (Calcium Silicate) as Safe. It's used at very low levels, and holds a clean, long-standing regulatory record.
Is calcium silicate the same as silicon dioxide (E551)?
No. Silicon dioxide (E551) is silica on its own; calcium silicate (E552) combines calcium with silica. Both are anti-caking agents used in powdered foods, and Goodnessly rates both Safe.
Don't decode labels by hand
Scan any product with the Goodnessly app to instantly see its full additive breakdown, kept current as new research like this comes to light.
Download our app to check additives in everyday foods
What is E552?
Calcium silicate — an anti-caking agent that stops powdery ingredients like salt and icing sugar from clumping together in humid conditions.
E552 (calcium silicate) is a fine white powder made from calcium and silica, used as an anti-caking agent. It's added in small amounts to powdered and granulated foods to absorb moisture and keep the product free-flowing rather than clumping together. Goodnessly rates it Safe.
Download our app to check additives in everyday foods
Read the FAQ →What is calcium silicate?
Calcium silicate is a fine, chalky white powder made by combining calcium compounds with silica. Its main job is absorbing excess moisture: added in tiny amounts to powdered or granulated foods, it prevents individual particles from sticking together, which is why table salt and powdered products stay free-flowing even in humid conditions rather than forming hard clumps.
What's it used for?
- Anti-caking agent in table salt
- Powdered sugar and icing sugar
- Spice blends and seasoning mixes
- Powdered dairy and coffee products
Where you'll find 552 on the shelf
Anywhere a powdered product needs to stay free-flowing.
Is calcium silicate safe? What the research says
Calcium silicate is used in very small amounts as an anti-caking agent, with a clean regulatory record.
| Region | Status | What this means |
|---|---|---|
| AU/NZ Australia & New Zealand (FSANZ) | Permitted | Permitted as an anti-caking agent with no specific quantity restriction in most categories. |
| EU European Union (EFSA) | Permitted, no ADI | Listed as E552, with no numerical Acceptable Daily Intake needed. |
| US United States (FDA) | GRAS | Holds Generally Recognized As Safe status for use as an anti-caking agent. |
Calcium silicate is used at very low levels, typically well under 2% of the finished product, since only a small amount is needed to achieve its moisture-absorbing effect.
- No significant regulatory changes: calcium silicate'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
- No population group has a specific safety-based reason to limit E552 at typical food-additive levels
Goodnessly rates E552 Safe. It's used at very low levels, and holds a clean, long-standing regulatory record.
How to spot it on a label
E552 is usually declared clearly. Look out for:
- Calcium silicate
- 552 or E552
- "Anti-caking agent (552)" in the ingredients list
Table salt and icing sugar are the most common places to find it.
Related additives
Frequently asked questions
Why does table salt sometimes contain calcium silicate?
Salt readily absorbs moisture from the air, which can cause it to clump. Calcium silicate is added in tiny amounts to absorb that moisture instead, keeping the salt free-flowing and easy to pour, especially in humid climates.
How much calcium silicate is actually in food?
Very little. It's typically used at well under 2% of the finished product, since only a small amount is needed to achieve its anti-caking effect.
Does Goodnessly rate E552 as safe, caution, or avoid?
Goodnessly rates E552 (Calcium Silicate) as Safe. It's used at very low levels, and holds a clean, long-standing regulatory record.
Is calcium silicate the same as silicon dioxide (E551)?
No. Silicon dioxide (E551) is silica on its own; calcium silicate (E552) combines calcium with silica. Both are anti-caking agents used in powdered foods, and Goodnessly rates both Safe.
Don't decode labels by hand
Scan any product with the Goodnessly app to instantly see its full additive breakdown, kept current as new research like this comes to light.
Download our app to check additives in everyday foods