Which of the following is a function of vitamin D?

Which of the following is a function of vitamin D?

• A. Increases calcium absorption
• B. Decreases bone remodeling
• C. Increases inflammation
• D. Decreases calcium absorption

Answer: (A)

Vitamin D’s main role here is to support calcium availability for bone health. The active form of vitamin D increases calcium absorption from the gut by upregulating calcium‑binding proteins in intestinal cells, which pulls calcium into the bloodstream for use in bone mineralization and to help keep blood calcium levels steady with parathyroid hormone. This is why increasing calcium absorption is the best description of vitamin D’s function in this context. It doesn’t decrease bone remodeling; in fact, adequate vitamin D supports proper bone turnover and mineralization. It isn’t something that raises inflammation—it’s associated with anti-inflammatory effects. And it doesn’t decrease calcium absorption—quite the opposite, it boosts it.

Vitamin D’s main role here is to support calcium availability for bone health. The active form of vitamin D increases calcium absorption from the gut by upregulating calcium‑binding proteins in intestinal cells, which pulls calcium into the bloodstream for use in bone mineralization and to help keep blood calcium levels steady with parathyroid hormone. This is why increasing calcium absorption is the best description of vitamin D’s function in this context.

It doesn’t decrease bone remodeling; in fact, adequate vitamin D supports proper bone turnover and mineralization. It isn’t something that raises inflammation—it’s associated with anti-inflammatory effects. And it doesn’t decrease calcium absorption—quite the opposite, it boosts it.