How does vitamin D work?
Vitamin D works at three sites in the body to regulate calcium levels.
- 1. In the intestines, it stimulates your body to absorb calcium from the foods you eat (or from supplements).
- 2. In the bones, it helps incorporate the absorbed calcium into the skeleton for storage and also regulates the cells involved in the process of bone building.
- 3. It works in your kidneys to help recycle calcium that would otherwise be excreted in the urine, so your bones can reabsorb it.
So vitamin D's primary role is to increase the availability of calcium for absorption. Without the help of vitamin D, levels of calcium in the blood, and ultimately in the bone, could be negatively affected.
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