FSN 101 Lecture Notes - Lecture 12: Dietary Reference Intake, Calcium Carbonate, Fluid Compartments
Document Summary
Calcium is the most abundant mineral in the body: 40% of all minerals in the body, accounts 1-2% of adult body weight. Calcium is absorbed by active transport and passive diffusion, depending on the availability of the active form of vitamin d. Bioavailability of calcium is decreased in the presence of tannins, fiber, phytates, and oxalates. 99% of calcium in the body is found in solid mineral deposits in the bones and teeth. The remaining 1% is found in intracellular fluid, blood and extracellular fluid. Calcium found in the body"s fluid plays a role in nerve transmission, muscle contractions, blood pressure regulation, blood clotting, and the release of hormones. Requires slightly acidic environment and vitamin d. Absorbed in upper part of small intestine because needs an acid environment for good absorption. Normally absorb 25% of calcium in food. Increase ~60% during time of need (pregnancy, infancy) Oxalic acid in some fruits and vegetables (spinach)