Calcium may serve as a protective factor against high blood pressure and colon cancer. A, C, D, and very possibly E. Magnesium, vitamin A, and fluoride are required for bone stability. Between 20 to 40 percent of the calcium ingested is absorbed. When calcium levels in the body are low, absorption is more efficient. After menopause, women s ability to absorb calcium may decrease.
Exercise encourages calcium absorption.
Calcium absorption takes place in the duodenum. The levels of calcium in the body are regulated by the parathyroid glands found in the neck. Vitamin D works with parathyroid hormone to regulate the amount of calcium in the blood and is needed for proper calcium absorption. The body uses both calcium and phosphorus to give firmness and strength to the bones. Excessive amounts of phosphorous cannot be used efficiently and may result in bone loss.