Amani Alghamdi. Slide 1

Transcription

1 Minerals in the body Amani Alghamdi Slide 1

2 The Minerals Small, naturally occurring, inorganic, chemical elements Serve as structural components

3 Minerals classification The minerals present in the body are classified into: Major elements (Macronutrients) Trace elements Essential trace elements Non-essential trace elements Slide 3

4 Major vs. Trace Major minerals LARGer Quantities (>5g) Calcium Magnesium Phosphorous Sodium Potassium Chloride Sulfur Trace Minerals SMALLer Quantities (<5g) Iron Zinc Copper Fluoride Selenium Iodine Chromium Manganese Molybdenum

5 Mineral Functions 1. Bone Health 2. Blood Health 3. Fluid Balance 4. Energy Metabolism 5. Antioxidant

6 Minerals for: Bone Health Major minerals LARGEr Quantities Calcium Magnesium Phosphorous Sodium Potassium Chloride Sulfur Trace Minerals SMALLer Quantities Iron Zinc Copper Fluoride Selenium Iodine Chromium

7 Minerals for: Blood Health Major minerals LARGEr Quantities Calcium Magnesium Sodium Potassium Chloride Phosphorous Sulfur Trace Minerals SMALLer Quantities Iodine IRON ZINC COPPER Fluoride Selenium Chromium Molybdenum Manganese

8 Minerals for: Fluid Balance Major minerals LARGEr Quantities Calcium Magnesium Phosphorous Sodium Potassium Chloride Trace Minerals SMALLer Quantities Iron Zinc Copper Fluoride Selenium Chromium Sulfur

9 Minerals for: Energy Metabolism Major minerals LARGEr Quantities Calcium Magnesium Phosphorous Sodium Potassium Chloride Sulfur Trace Minerals SMALLer Quantities Iron Zinc Copper Fluoride Selenium Iodine Chromium

10 Antioxidant - Selenium Works with Vitamin E

11 Calcium Distribution: Most abundant mineral in body 2% of body weight Provides structure to bones and teeth Calcium exists in two forms that have quite different functions % of total body calcium is present in the bone and teeth as crystals called hydroxyapatite. 2. 1% of total body calcium is present in body fluid as an ionized form and it has an important part for the physiologic activity. Slide 11

12 Functions of Calcium I. Calcification of bones and teeth. II. Blood clotting as activator of thrombokinase. III. It is important for maintenance of the heart beat. IV. Regulate the transport of ions across cell membranes and it is particularly important in nerve transmission and muscle contraction. V. It is cofactor for several enzymes. Slide 12

13 Calcium balance The skeleton serves as a bank from which the blood can borrow and return Ca²+ as needed. Withdrawal and deposition of Ca²+ are regulated by hormones sensitive to blood level of Ca²+. These hormones are: Parathyroid hormone (PTH) Calcitonin: ( Calcium lowering hormone) Slide 13

14 Parathyroid hormone (PTH) A decrease in the calcium concentration in the blood stimulates the release of PTH from parathyroid gland. PTH: increase serum Ca²+ and decrease serum phosphorus: It increase urinary excretion of phosphorous and decrease urinary excretion of calcium. Stimulates release of calcium from bone. Increase the synthesis of 1.25 dihydroxy cholecalciferol form of vitamin D which increases absorption of calcium from the intestine. Slide 14

15 Calcitonin ( Calcium lowering hormone) A rise in the calcium concentration in the blood, stimulates the secretion of the calcitonin by the thyroid gland. Calcitonin: decrease serum Ca²+ level (opposite PTH) by: Decrease withdrawal of Ca²+ from bone (dissolution of bone). Increase Ca²+ excretion by the kidney. Inhibit synthesis of 1.25 dihydroxy cholecalciferol Slide 15

16 Calcium recommendations Calcium recommendations during adolescence are set high (1300 mg/day) to ensure that the skeleton will be strong and dense. Between the ages of 19-50, recommendations are lowered to 1000 mg/day. Over 50, the recommendations are raised again to 1800 mg/day to minimized bone loss. Mosby items and derived items 2006 by Mosby, Inc. Slide 16

17 Dietary Calcium Sources Dairy: milk, cheese, yogurt Broccoli, dark green vegetables Orange juice with calcium Salmon, sardines with the bones

18 Dietary Calcium Sources Milk and milk products typically contain more calcium than other food sources Milk also contains vitamin D and lactose which can enhance calcium absorption

19 Dietary Calcium Sources Not Only Milk Other dairy options: Low-fat cheese in a sandwich Yogurt dips with vegetables Low-fat shredded cheese on soups and salads Cottage cheese

20 Abnormal level of Ca²+ May be due to disease of: parathyroid, kidney disturbed vitamin D level. Mosby items and derived items 2006 by Mosby, Inc. Slide 20

21 Ca and osteoporosis Osteoporosis is a silent thief. It leads to progressive loss of bone mass that occurs in the elderly of both sexes but is pronounced in postmenopausal women (mostly women 45 years or more). It is characterized by frequent bone fractures, which are the major disability among the elderly. Mosby items and derived items 2006 by Mosby, Inc. Slide 21

22 Bone Mass and Age Bone mass: Decreases with age Peaks around 30

23 Ca and osteoporosis Patient life-style may influence calcium metabolism, immobilized or sedentary individual tends to show bone loss, while patient that exercise regularly tend to increase their bone mass. Mosby items and derived items 2006 by Mosby, Inc. Slide 23

24 Ca and osteoporosis Although estrogen replacement is the most effective prevention of postmenopausal bone loss, calcium supplementation (often given in combination with vitamin D). Further reduces the risk of fracture due to bone loss, particularly in elderly patients Mosby items and derived items 2006 by Mosby, Inc. Slide 24

25 Rickets Rickets is a disorder caused by a lack of vitamin D, calcium, or phosphate. It leads to softening and weakening of the bones. There is low serum and urinary calcium and phosphorus level. Mosby items and derived items 2006 by Mosby, Inc. Slide 25

26 Phosphorous Distribution: Second most abundant mineral in the body Critical role in bone formation Gives bones and teeth strength and rigidity Slide 26

27 Functions of phosphorous: Enters in formation in bones and teeth. Formation of high energy compounds as ATP. Enters in the structure of nucleotides and nucleic acids (genetic material). It is important for the biosynthesis of phospholipids present in cell membrane. It is in carbohydrate metabolism as hexose ester (glc- 6-P and Fr-6-P). It is acts as buffer to maintain the acid-base balance of cellular fluid. Enter the formation of coenzymes as NADP. Mosby items and derived items 2006 by Mosby, Inc. Slide 27

28 Sources of phosphorous Milk and milk products Proteins as meat and fish products. Mosby items and derived items 2006 by Mosby, Inc. Slide 28