From the sea, not the quarry

Most of the calcium in most supplements is calcium carbonate, and most calcium carbonate is limestone. Ground rock. It is cheap and it is technically calcium, and that is roughly where the case for it ends.

Ours comes from a red seaweed called Lithothamnion that grows in cold, clean water off the coast of Iceland. As it grows it draws minerals out of the seawater and builds them into itself, so that when it is harvested and dried you get calcium in the form a living plant made it, around a third of it calcium by weight, with magnesium and some seventy trace minerals that arrived at the same time. The ingredient is Aquamin F.

Calcium is needed for the maintenance of normal bones and normal teeth, and it is one of the minerals we knew we wanted from a food rather than a quarry. We believe the body knows what to do with a mineral that came out of a plant in a way it never quite does with ground rock, because that is the form it has been eating for a couple of hundred thousand years.

If you have ever looked at a tub and wondered why the calcium in it costs so little, now you know.