Which hormone decreases blood calcium levels by moving calcium into storage in bones?

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Calcium balance is controlled by hormones that move calcium into bone when levels are high. Calcitonin is released by the thyroid in response to elevated blood calcium and acts to slow bone breakdown by osteoclasts and promote calcium deposition by osteoblasts. The result is a decrease in calcium circulating in the blood as more calcium is stored in bone. This contrasts with parathyroid hormone, which raises blood calcium by increasing bone resorption, kidney reabsorption, and vitamin D activation. ACTH has no primary role in calcium regulation, and thyroxine mainly influences metabolism and bone turnover rather than directly driving calcium into storage.