Calcium carbonate is chalk, essentially, quarried from rock to firm, whiten and fortify. It is a mineral, so it sits on the vegan side, with a rare shell-derived footnote.
Usual sourceMineral rock (limestone, chalk)
E numberE170
VerdictUsually vegan
Where it hides
Fortified plant milks and flour
Supplements and antacids
Toothpaste
Firming and anti-caking in foods
What it is
Calcium carbonate is one of the most abundant minerals on Earth, used to whiten, firm, reduce acidity and add calcium. Its industrial source is rock:
Primary source 01 / 01
Industrially important source rocks which are predominantly calcium carbonate include limestone, chalk, marble and travertine.
Food and supplement calcium carbonate is generally mined from limestone, which is a mineral and vegan, and it is a common way to fortify plant milks and flour with calcium. The reason the verdict is usually rather than always is that calcium carbonate can also be sourced from shells or eggshells, so someone avoiding all animal inputs may want a mineral-sourced or certified-vegan product.
Silicon dioxide (silica, E551)Silicon dioxide is sand, essentially, added to keep powders from clumping. There is nothing animal about a mineral.
Bone phosphate (E542)Bone phosphate, additive E542, is exactly what it sounds like. It is ground animal bone, used as an anti-caking agent and a mineral source.
Bone char sugarSome cane sugar is whitened by filtering it through charred cattle bone. The sugar holds no bone, but the process is animal, so it depends on the brand.
Calcium and bone health on a vegan dietThe Evidence · This is the page where being on veganism's side means telling you the uncomfortable finding: vegans break more bones in the data, and calcium is the lever that moves it.
Frequently asked
Is E170 vegan?
Usually. Food-grade calcium carbonate is generally mined from mineral rock like limestone, so it is vegan. It can occasionally be from shells, so a certified or mineral-sourced product removes any doubt.
Is the calcium in plant milk vegan?
The calcium carbonate or other calcium salt used to fortify plant milk is generally mineral-derived and vegan. It is one of the ways plant milks match dairy on calcium.
The same clear-eyed sourcing behind these verdicts, applied to each day’s news: what actually moved veganism forward, quoted and checked before you read it. One short brief, free.
