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How does vitamin D deficiency cause rickets in children?

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rickets, a nutritional disease — nutritional disease Children with rickets. The disease, which most commonly strikes children, causes bone deformities such as bowlegs. Rickets is caused by a lack of vitamin D or calcium.

Vitamin D deficiency causes rickets in children by disrupting the body's ability to maintain the bone rigidity necessary for healthy growth.1

Under normal conditions, the active form of vitamin D, known as calcitriol, stimulates the small intestine and kidneys to absorb calcium and phosphate. These minerals are then deposited in the bone matrix as calcium phosphate, which provides structural strength.12

When vitamin D levels are insufficient, the body cannot absorb these minerals efficiently, leading to low serum calcium and phosphate concentrations. In response, the parathyroid glands secrete parathormone, which pulls calcium from the bones to maintain blood levels. Consequently, while the protein matrix of the bone continues to grow, it remains poorly calcified and soft. This softening leads to the characteristic skeletal deformities of rickets, such as bowed legs, stunted growth, and enlarged bone ends.123