Water and Minerals: The Ocean Within

1. Chapter 8 Water and Minerals: The Ocean Within

2. Water and Minerals • Minerals • Naturally occurring • Inorganic • Homogenous • Chemical elements • Major minerals • Essential nutrients • Found in the body in amounts exceeding 5 grams • Trace minerals • Essential nutrients • Found in the body in amounts less than 5 grams With death all that we leave behind is about 5 pounds of minerals

3. Water • The body needs more water per day than any other nutrient • You survive a deficiency of any other nutrient for months or years • You only survive a few days without water • In less than a day, a lack of water alters the body’s chemistry and metabolism • Water makes up ≈60% of an adult’s body weight • Water is found in--Blood vessels, cells, chemical structure of cells, tissues, organs • Water participates in many chemical reactions

4. Why Is Water the Most Indispensable Nutrient? Almost a Universal solvent • Dissolves amino acids, glucose, minerals, etc. for transport • Fatty substances are packaged with water-soluble proteins Body’s cleansing agent • Removes nitrogen wastes, before they build up to toxic levels • Kidneys filter wastes and excrete them as urine

5. Why Is Water the Most Indispensable Nutrient? • Water resists compression • Acts as a lubricant and cushions joints • Cushions spinal cord and fetus • Lubricates the digestive, respiratory tract, and tissues that are moistened with mucus • Keeps pressure on the retina and lens • Maintains body temperature • Sweat cools the body via the skin, exhaled breath and feces

6. 0 Water • Water balance • Intake needs to equal water loss • Dehydration • Water loss • Progression of symptoms: thirst  weakness  exhaustion and delirium  death • Water intoxication • Dilution of body fluids from excessive water ingestion • Symptoms: headache, muscular weakness, lack of concentration, poor memory, loss of appetite

7. The Body’s Water Balance • Body’s water content • Varies by pounds at a time • Especially in women who retain water during menstruation • High-salt meal leads to water retention • Fluctuation in water weight does not reflect gain or loss of body fat

9. How Much Water Do I Need to Drink in a Day? • DRI meets ≈80% of day’s need for water • Men: 13 cups of fluid from beverages and drinking water • Women: 9 cups of fluid from beverages and drinking water • Remaining water need is met from consumed foods • Body produces water from the breakdown of energy-yielding nutrients

10. How Much Water Do I Need to Drink in a Day? • Sweating increases water needs • Doing physical work outdoors in hot weather • An athlete in training • Caffeine behaves as a diuretic • The results of research is mixed • People who habitually consume caffeine may adapt to its diuretic effects • An occasional caffeinated beverage can contribute fluid to the body

11. Are Some Kinds of Water Better for My Health Than Others? • Hard water • High calcium and magnesium concentrations • Soft water • High sodium concentration • There is some evidence that soft water may aggravate hypertension and heart disease • Mineral contaminants are more easily dissolved in soft water--Cadmium, lead EPA is responsible for ensuring that public water systems meet minimum standards for protection of public health

12. Consumer Corner: Bottled Water • ≈1 in 15 households use bottled water • 250-10,000 times the cost of tap water • Not safer than tap water • ≈25% of bottled water is drawn from the tap • FDA tests bottled water • Standards substantially less rigorous than those applied to U.S. tap water

13. Body Fluids and Minerals • Cells cannot directly regulate the passage of water across their membranes • Water content of cells is regulated by major mineral salts dissolved in body fluids Salts are charged articles (ions) called electrolytes • The pumping of salts across their membranes regulates cells’ water balance What are the salts??????

14. Body Fluids and Minerals • Salts are composed of charged articles (ions) called electrolytes -potassium chloride, sodium chloride • When dissolved particles are separated by a membrane water will flow to the side of greater dissolved particle concentration • This is how cells regulate their water content

16. Body Fluids and Minerals • To control the flow of water, cells must expend energy moving electrolytes from one compartment to another • Proteins pump mineral ions across cell membranes • The result is fluid and electrolyte balance

18. Body Fluids and Minerals • A disturbed fluid balance can cause a severe illness • In vomiting or diarrhea • The loss of water from the digestive tract pulls fluid from between the cells in every part of the body  water is lost from cell interiors • Kidneys conserve water by increasing sodium concentrations outside of cells  more water loss from cells • Result: fluid and electrolyte imbalance

19. Body Fluids and Minerals • Minerals play a role in acid-base balance • In pure water H+ and OH- ions exist in equilibrium • When minerals are dissolved in water • Some major minerals give rise to acids; increased H+ • Other minerals give rise to bases; increased OH- • The maintenance of a nearly constant pH is critical to life How much does the pH of the blood vary?????

21. Body Fluids and Minerals • Some proteins and some mineral salts act as buffers, molecules that gain or lose H+ ions as needed to correct pH • Kidneys help by excreting more or less H+ • Lungs help by excreting more or less carbon dioxide (Dissolved in the blood, carbon dioxide forms carbonic acid)

22. The Major Minerals • Calcium • Chloride • Magnesium • Phosphorus • Potassium • Sodium • Sulfate

23. Calcium • Role • Most abundant mineral in the body • ≈99% stored in bone and teeth • Part of bone structure • Bone serves as a calcium reserve, releasing or removing calcium from the blood • Minerals of the bone are constantly forming and dissolving

26. Calcium • Role In Body Fluids • ≈1% of calcium is in the fluids outside and within cells • Regulates the transport of ions across cell membranes; important in nerve transmission • Helps maintain normal blood pressure • Essential role in blood clotting • Essential for muscle contraction (heartbeat) • Secretion of hormones, digestive enzymes, and neurotransmitters • Activates cellular enzymes

27. Calcium • Role of calcium • The body maintains a constant calcium concentration in the blood • The skeleton serves as a calcium reservoir • Blood calcium is regulated by hormones • When calcium intake is inadequate normal blood calcium is maintained at the expense of the bones

28. Calcium • When calcium need increases • Calcium absorption from the intestine increases • Loss of calcium from the kidneys is reduced • Adults absorb ≈25% of dietary calcium • Percent increases as dietary calcium decreases

29. Calcium • Some bone loss is an inevitable consequence of aging • By the late 20s or 10 years after adult height is reached, the skeleton no longer adds significantly to bone density • After ≈40 years of age, regardless of calcium intake, bones begin to reduce density • Loss can be slowed by a diet and physical activity

30. Calcium • To protect against bone loss, high calcium intakes early in life are recommended • A calcium-poor diet during the growing years may prevent achieving peak bone mass • Insufficient bone calcium increases the risk of osteoporosis (adult bone loss) • Recommended intakes are high for children and adolescents

32. Phosphorus • Second most abundant mineral in the body • Concentration in the blood is less than half that of calcium • Role • ≈85% is combined with calcium in the crystals of the bone and teeth • Phosphorous salts are buffers that help maintain the acid-base balance of cellular fluids • Part of DNA and RNA • Phosphorus compounds carry, store, and release energy of energy nutrients • Phosphorous compounds assist enzymes and vitamins in extracting the energy from nutrients • Forms part of phospholipids • Present in some proteins

33. Phosphorus • Need and deficiency • Needs are easily met by almost any diet • Deficiencies are unknown • Source • Animal protein is the best source

35. Magnesium • Barely qualifies as a major mineral • Only ≈1 ounce is present in the body of a 135-pound person • Half in the bones • The rest in muscles, heart, liver, other soft tissues • 1% in body fluids

36. Magnesium • Role • Assists in the functioning of more than 300 enzymes • Releases energy from energy-yielding nutrients • Directly affects the metabolism of • Potassium, Calcium, Vitamin D • Acts in the cells of all soft tissue • Making protein • Releasing energy • Works with calcium for the functioning of muscles • Promotes resistance to tooth decay by holding calcium in tooth enamel

37. Magnesium • Deficiency • Inadequate intake, Vomiting, Diarrhea, Alcoholism, Protein malnutrition, Diuretic use • Deficiency symptoms are rare in healthy people • Toxicity • Rare but can be fatal • Only occurs with high intakes from Supplements or magnesium salts • May occur in older people who abuse magnesium-containing laxatives, antacids, etc. • Toxicity symptoms • Severe diarrhea • Acid-base imbalance • Dehydration

40. Sodium • Positive ion in sodium chloride (table salt) • 40% of the weight of sodium chloride • Role • Fluid balance • Electrolyte balance • Maintenance of extracellular fluid balance • Acid-base balance • Muscle contraction • Nerve transmission

41. Sodium • Deficiency • No known human diet lacks sodium • Most foods include more salt than is needed • Body absorbs sodium freely • Kidneys filter excess sodium out of the blood into the urine • Kidneys will also conserve sodium • Small sodium losses occur in sweat

43. Sodium • Sodium Intake • Adults in the U.S. exceed the Tolerable Upper Intake Level by more than a third • Asian peoples, whose staple sauces and flavorings are based on soy sauce and MSG, may consume the equivalent of 30 to 40 grams of salt per day

44. Sodium • Sodium and Blood Pressure • Communities with high salt intake experience high rates of hypertension, cardiovascular disease, and cerebral hemorrhage • As sodium intake increases, blood pressure rises • death from cardiovascular disease increases • In salt-sensitive people, the more salt they eat the higher their blood pressure • People with diabetes, hypertension, kidney disease • People of African descent, those whose parents had high blood pressure, and anyone over the age of 50

45. Sodium • A dietary approach that may help salt-sensitive and non-salt-sensitive people is the DASH diet • This diet often achieves a lower blood pressure than restriction of sodium alone • DASH diet • Greatly increased intake of fruits and vegetables • Adequate amounts of nuts, fish, whole grains, low-fat dairy products • Small portions of red meat, butter, and other high-fat foods and sweets • Salt and sodium are greatly reduced

46. Sodium • Low potassium intake raises blood pressure • High potassium intake helps prevent and correct hypertension • Physical activity also lowers blood pressure

47. Sodium • Controlling Salt Intake • The salt shaker may contribute as little as 15% of total salt consumed • Processed and fast foods are the source of nearly 75% of salt in the U.S. diet

49. Potassium • The main positively charged ion inside the body’s cells • Role • Maintenance of fluid balance • Maintenance of electrolyte balance • Maintenance of cell integrity • Maintenance of heartbeat

50. Potassium • Deficiency • Causes sudden death Fasting or severe diarrhea in children with kwashiorkor and people with eating disorders are thought to be due to heart failure caused by potassium loss • Low potassium intake • Salt-sensitive hypertension becomes worse • Metabolic acidity increases • Calcium losses from bones accelerates • Kidney stone risk increases