[11] Osteocalcin is secreted solely by osteoblasts and is thought to play a role in the body's metabolic regulation.

[12] In its carboxylated form, calcium is bound directly to the bone and thus concentrates here.

In its uncarboxylated form, osteocalcin acts as a hormone in the body, signalling in the pancreas, fat, muscle, testes, and brain.

Injections of high levels of osteocalcin alone can trigger an ASR in the presence of adrenal insufficiency.

In many studies, osteocalcin is used as a preliminary biomarker for the effectiveness of a given drug on bone formation.