Their Role in the Health of the Body and Especialy the Oral Cavity
Provides rigidity and strength to the bones and teeth
Serum calcium performs specific functions: Contraction and relaxation of heart muscle. Helps in blood clotting Low blood calcium will increase the irritability of nervous tissue and may cause tetany. Activate enzymes such as pancreatic lipase and alkaline phosphatase. Activates rennin which causes curding of milk during its digestion Necessary for the release of NTs (neurotransmitters) Regulates transport of ions across cell membranes
Active process Reqiures Vitamin D and calcium-binding protein 20-30% of calcium is absorbed and the rest are excreted in the feces, urine and perspiration.
1. Needs of the body Growing child, pregnant, a person healing from a bone fracture- increased calcium absorption2. Gastric acidity Acidity in the stomach converts the insoluble calcium salts into more soluble types3. Hormonal influences Parathormone and calcitonin
4) Vitamin D Deficiency in Vit. D- decreased calcium absorption5) Lactose The disaccharide lactose found in milk promotes calcium absorption. Lactose in ileum change the intestinal bacteria lowering the pH thus increase calcium absorption6) Citric acid 6) Its low pH promotes calcium absorption
6) Oxalic and phytic acid Intake of foods rich in oxalic such as spinach and phytic acids found in cereal grain and meal flour causes formation of insoluble complexes (calcium salts) within intestinal lumen that leads to increased calcium absorption.7) Fat Decreased fat, bile or salts produces insoluble calcium thus increase calcium absorption.
11) Emotional reactions Stress may cause hormonal changes that affects calcium metabolism12) Exercise Weight-bearing exercise helps maintain calcium in bone.
calcium and phosphorus are stored in the trabeculae but can be withdrawn out when it is needed in the blood The blood and tissue calcium serve as reserves The degree of bone development amount of calcium deposited in are directly related to the amount of the calcium available from the diet.
Out of the 100og dietary intake of calcium, 700 – 800g are excreted in feces but it could be less than that when the dietary intake is low. During lactation, mother loses 150 -300mg of calcium daily but normally, it is not affected because of human adaptability. Excess calcium from the bone are excreted in the urine Unimportant daily lost of 15mg of calcium through perspiration
Calcium in serum is regulated by the: Parathormone (PTH) Calcitonin -serum calcium rises, PTH is inhibited -serum calcium falls, secretion of PTH increases -serum calcium rises, calcitonin increases Role of Bone, Kidney, and Intestine Kidney can resorb calcium Intestine - acidity Bone – activity of the osteoblast and osteoclast. How?
Vitamin D Necessary for normal intestinal absorption of calcium and helps maintain bone cells, thus regulating serum calcium and serum phosphate levels.
Cheddar cheese – highest level of calcium Best sources are hard cheese, milk, and dark green leafy vegetables (the darker the green, the more calcium), Good sources are ice cream, blackstrap molasses, broccoli, baked beans, dried legumes, and dried figs. Fair sources are cottage cheese, string breans, parsnips, lima beans lettuce and other sald greens, eggs and bread.
Calcium carbonate or oyster shell calcium is frequently recommended for persons who cannot eat dairy products. When children refuse to drink milk, it should be incorporated either in fluid or powder form in soups, gravies, casseroles, or baked goods.