Download
water and minerals n.
Skip this Video
Loading SlideShow in 5 Seconds..
Water and Minerals PowerPoint Presentation
Download Presentation
Water and Minerals

Water and Minerals

237 Vues Download Presentation
Télécharger la présentation

Water and Minerals

- - - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript

  1. Water and Minerals

  2. Water • ~60% of adult body weight is water • % is higher in kids • More muscle, more water • Changes in water level can quickly and dramatically impact weight

  3. Water • Functions: • Carries nutrients through the body • Blood and lymph systems • Carries wastes out of the body • urine • Lubricant and cushion around joints, eyes, spinal cord, fetus… • Component of secretions • Mucus, digestive secretions

  4. Water • Functions cont’d: • Aids in regulation of body temp. • Needed for many metabolic reactions • Digestion of proteins, fats and starches • All hydrolysis reactions require the input of water

  5. Water • Maintaining water balance • Goal is to balance water output and input • Water Loss: • Urine • Feces • Sweat (kids and elderly sweat less) • Exhale moist air

  6. Water • Water Input • Water • Other fluids • Water in foods • Water made in metabolism

  7. Water Sources • Good sources of water • Water • Juice • Sports drinks • Soups • Fruits and vegetables

  8. Water Sources • Poor Sources – all are diuretics • Caffeine containing coffee, tea, sodas • Alcohol

  9. Water Intake • Recommend ~8-12 cups/day • text 11-15 cups • Amount needed depends upon: • Calories eaten, more calories, more water • Level of exercise • Impacts ______ and _______ • Recommend 3 cups water/lb loss sweating • Climate

  10. Blood Volume • Blood volume is regulated by the brain and kidneys • When blood volume is low: • Ion concentrations rise

  11. Decreased Blood Volume Consequences low blood volume: • Urine production is reduced • Dark yellow urine • Blood vessels narrow to raise blood pressure • Hypothalamus triggers thirst response • Thirst response ALWAYS lags behind the need for water • Thirst response diminished in elderly

  12. Dehydration • When a water deficiency develops slowly thirst usually takes care of it • When water deficiency occurs quickly dehydration occurs  VERY SERIOUS

  13. Dehydration • Symptoms of mild dehydration: • Thirsty • Tired and weak • Impaired performance • Impatient and irritable • Flushed skin • Decreased urine output • Dry mouth

  14. Dehydration • Severe Dehydration – SERIOUS • Skin pale and dry • Headache, can’t concentrate • Shallow rapid breathing • Increased heart rate • Dizziness, delirium, collapse • Stop sweating • Overheat ….VERY SERIOUS

  15. Dehydration and Over-Heating • Over-heating – athletes and babies die from this every year (others too) • Symptoms, in addition to dehydration: • Shock • Seizures • Coma • Death

  16. Hyponatremia • “Water intoxication” • Fairly rare • Most often occurs with rapid water consumption combined with heavy sweating • Results in a potentially deadly drop in blood levels of sodium.

  17. Electrolytes • Electrolytes are dissolved ions in body fluids • Ion = charged particle • Ions attract water

  18. Electrolytes • Major extracellular ions: • Sodium Na+ Na+ • Chloride Cl - • Major intracellular ion: • Potassium K + Cl - K+

  19. Sodium – Na+ • Major ion outside of cells • Functions: • Primary regulator of extracellular fluid volume • Helps maintain acid-base balance • Essential for nerve and muscle contraction

  20. Sodium – Na+ • Absorption • Absorbed in SI into capillaries • Recommended intake • Minimum 500 mg/day • Maximum 2400 mg/day • A little more than 1 teaspoon

  21. Sodium – Na+ • Food sources • Primary sources of sodium are processed foods, not the salt shaker • Examples of high sodium foods:

  22. Sodium – Na+ • Control of high blood Na+ levels: • Goal is to readjust the sodium to water levels to normal • Thirst mechanism triggered • Drink more water • Kidneys filter the Na+ out and excrete it in the urine (if enough water)

  23. Sodium – Na+ • Low blood Na+ levels: • First ion (with Cl-) to be lost with sweating, bleeding, vomiting, diarrhea…. • In response to low Na + levels, kidneys keep Na+ and excrete more K+ • When Na+ levels drop in these ways you need to replace both the ions and the water

  24. Sodium – Na+ • Can raise levels of Na+ and water by: • Ingesting sports drinks • Drinking dilute juices (add a little salt) • Combining salt containing foods with fluids • Salt pills are never recommended • Pure water may not be the answer either….

  25. Sodium – Na+ • Sodium and Hypertension • High sodium intake is associated w/ hypertension in many people (salt sensitive) • Populations at risk • African descent • Family or personal history of hypertension • Over 50 • Diabetic or obese • Chronic kidney disease

  26. Sodium – Na+ • Lowering blood pressure • Reduce sodium intake and increase potassium intake • Reduce intake of processed foods, increase intake of fresh foods • DASH Diet • Lose weight

  27. Sodium – Na+ • High Na+ intake is associated with increased calcium excretion • May contribute to osteoporosis

  28. Potassium - K+ • Major electrolyte inside cells • Functions: • Plays a major role in maintaining fluid and electrolyte balance • Needed for nerve and muscle contraction • Required for a steady heart beat • Plays a role in carb and protein metabolism

  29. Potassium - K+ • Absorption – occurs in SI  blood • Recommended intake • Minimum 4700 mg/day

  30. Potassium - K+ • Food sources • Fresh foods (intact cells) • Fresh fruits and vegetables • See page __________ • Processing lowers K+ levels and raises Na+ levels

  31. Potassium - K+ • Potassium and Health • Low K+ intake is associated with increased blood pressure • High K+ intake may reduce or help prevent hypertension • High K+ intake may lower risk of stroke

  32. Potassium - K+ • Potassium deficiency • Most common electrolyte imbalance • Occurs most often due to excessive losses not a low intake • Symptoms • Muscular weakness (first symptom) • Confusion • Paralysis • Heart failure may occur

  33. Potassium - K+ • Potassium Toxicity • Body excretes excess in urine • Any toxicity will come from supplements, not foods • Muscle weakness and vomiting • A shot of potassium into a vein can cause the heart to STOP = death

  34. Calcium – Ca+2 • Ca is the most abundant mineral in the body • 99% in bones and teeth as hydroxyapatite • On a collagen matrix • 1% in blood as Ca+2 • Blood level of calcium is tightly controlled

  35. Calcium • Absorption • Occurs in the SI • Occurs best in an acidic environment • Best absorption in first section of SI • To be absorbed the Ca must bind to a Ca binding protein • Vit D activates the binding protein

  36. Calcium • % Absorption • Adults: ~30% • Kids: ~ 50-60% • Pregnancy: ~50%

  37. Calcium – Ca+2 • Functions • Bones • Key component (along with P) of bone structure • Serve as a calcium bank for the blood

  38. Calcium – Ca+2 • Functions - In Blood • Regulates muscle contraction • Needed for nerve function • Plays a role in blood clotting

  39. Calcium – Ca+2 • Functions – In Blood • Plays a role in hormone secretion • Activates some enzyme reactions • Activates protein (calmodulin) that helps regulate blood pressure

  40. Calcium Balance • Calcium Balance • Calcium is constantly moving in and out of bones • Intake must be adequate to replace all Ca taken out of bones

  41. Calcium Balance • When blood calcium levels go up: • Hormones and vit D promote deposition of Ca into bones • Key hormone for lowering blood Ca is calcitonin • Key hormone for raising blood calcium is parathyroid hormone (PTH)

  42. Calcium Balance • Calcitonin – lowers blood Ca • Inhibits vit D activation • Less Ca absorbed • Prevents Ca reabsorption in kidneys • More Ca excreted in the urine • Slows breakdown of bones

  43. Calcium Balance • When blood calcium levels are low: • Key hormone in raising Ca levels is parathyroid hormone • Calcium absorption goes up in SI • assuming Ca in diet and vit D present • Bones release more Ca into blood • Kidneys excrete less Ca

  44. Calcium Requirements • Calcium Adequate Intake • Adults 19-50: 1000 mg/day • Adults 51+: 1200 mg/day • Pregnant or lactating: 1000 mg/day • Kids/teens: 1300 mg/day

  45. Calcium Sources • Food Sources • Dairy products – great source of Ca • Many also contain vitamin D • Drawback - many are high in fat and cholesterol

  46. Calcium Sources • Food Sources • Dark green leafy vegetables • Fairly good = mustard greens, kale, broccoli • Not as good = spinach and Swiss chard • Contain oxalates and phytates which lower the bioavailability of the Ca • 8 cups of spinach = 1 glass milk

  47. Calcium Sources • Food Sources • Nuts and legumes (limited calcium) • Soy milk is often Ca enriched • Calcium fortified products • Orange juice • Soy and rice milk • Cereals…..

  48. Calcium Sources • Food Sources • Other sources • Sardines (eat the bones!) • Oysters • Molasses • ??? Maple sugar water