Which of the following is NOT listed among abnormalities seen with vitamin D deficiency?

• A. Hypocalcemia
• B. Osteomalacia
• C. Osteoporosis
• D. Hypercalcemia

Answer: (D)

Vitamin D is essential for calcium absorption and bone mineralization, so deficiency disrupts this system in clear ways. When there isn’t enough vitamin D, calcium absorption from the gut drops, and serum calcium can fall (hypocalcemia). The body responds by increasing parathyroid hormone, which pulls calcium from bone, contributing to bone demineralization. This mechanism explains why osteomalacia (softening of bone due to poor mineralization) is a classic finding in vitamin D deficiency.

Osteoporosis can be associated with prolonged low vitamin D because reduced calcium availability and secondary hyperparathyroidism can accelerate bone loss, especially in individuals with other risk factors. However, the hallmark abnormality that does not fit vitamin D deficiency is hypercalcemia. Excess vitamin D or other conditions can raise calcium levels, so hypercalcemia is not expected in a deficiency state.