1. Major Minerals and Water
Jamie Pope, Steven Nizielski, and Alison McCook
NUTRITION
for a Changing World
FIRST EDITION
Chapter 13
Major Minerals and Water
Potassium Power
© 2016 by W. H. Freeman and Company & Scientific American

2. Chapter 13
Objectives
Identify the major minerals that have structural functions in the body
Discuss the role of calcium in bone health and the consequences of inadequate intake
Describe factors that may influence the bioavailability of minerals in the body
Identify the major minerals that serve as electrolytes, and describe their role in fluid balance
Describe the effect that dietary sodium and potassium have on blood pressure
Identify primary sources of calcium, sodium, potassium, and magnesium in the diet
Identify at least five functions of water in the body
Identify the sources of water for the body and the ways water is lost from the body
Describe how antidiuretic hormones regulate water balance

3. Diets Low in Sodium Could reduce the risk of hypertension
Lewis K. Dahl conducted pioneering research on the relationship between sodium and hypertension.
Rats that were fed high-sodium diets had increased high blood pressure. Rats that were fed high-potassium diets had lower blood pressure.

4. Overview of Minerals Major minerals Trace minerals
Requirement greater than 100 mg/day
Trace minerals
Requirement less than 100 mg/day

5. Overview of Minerals Diverse regulatory and structural functions
Many act with enzymes as cofactors
Have an electric charge and are, therefore, ions

6. Major Minerals Sodium Potassium Chloride Calcium Magnesium Phosphorus
Sulfur

7. Trace Minerals Iron Zinc Copper Iodine Selenium Molybdenum Fluoride
Manganese
Chromium

8. Mineral Absorption and Bioavailability
Bioavailability affected by
Deficiency in a mineral
Increased need for a mineral
Binders:
Phytates – Whole cereal grain
Oxylates – Found in Spinach and
some vegetables
Polyphenols – Present in coffee
and tea
Minerals – Can limit bioavailability
by chemically binding
to minerals

9. Minerals in Food Tap water Plants Animal foods
Hard water contains calcium and magnesium
Soft water contains sodium
Plants
Reflect mineral content of the soil
Animal foods
Processed and refined foods
Whole, unprocessed foods
Processing tends to reduce mineral content. Although cooking doesn’t destroy minerals, boiling can leach minerals into cooking water.

10. Structural Roles in the Body
Bone formation and maintenance
Calcium
Magnesium
Phosphorus

11. Calcium (Ca) Most abundant mineral in the body Functions
99% in bone and teeth
1% in body cells and fluids
Functions
Strengthening bone and teeth
Blood clotting
Hormone secretion
Muscle contraction
Nerve transmission

12. Calcium Homeostasis When calcium levels fall
Parathyroid gland releases parathyroid hormone (PTH)
PTH stimulates production of active vitamin D
Increases calcium absorption in the intestine
PTH and activated vitamin D mobilize calcium from the bone and decrease calcium excretion from the kidneys

13. Bone Remodeling

14. Dietary Sources of Calcium
AI = 1,000 mg/day for adults 19 to 50 years of age

15. Calcium Deficiency

16. Calcium Toxicity Upper tolerable intake level (UL) is 2,500 mg
Constipation
Interference with iron absorption
Hypercalcemia

17. Magnesium (Mg) Function Cofactor in more than 300 chemical reactions
50% to 60% is found in bones
Role in the transport of ions across cell membranes for muscle contraction, nerve impulse conduction, and maintaining heart rhythm
Involved in extracting energy from carbohydrates, proteins, and fats
Role in protein production
Necessary in activating vitamin D
Bone health

18. Dietary Sources of Magnesium

19. Magnesium Deficiency
Kidneys will excrete less and body will absorb more
Osteoporosis
Increases the risk for
Atherosclerosis
Cancer
Diabetes
Hypertension

20. Magnesium Toxicity Rare from diet
Toxicity from supplement misuse does occur

21. Phosphorus (P) In every cell of the body Function
Component of bone and cartilage, phospholipids, DNA, and RNA
Involved in energy metabolism
Regulates many enzymes
Helps maintain acid-base balance

22. Phosphorus (P) Deficiency Overconsumption
Rare, as found in protein-rich foods and food additives
Overconsumption
Increased levels associated with cardiovascular disease, particularly in people with kidney disease

23. Sulfur (S) Component of protein Present in thiamin and biotin
Present in cysteine and methionine
Present in thiamin and biotin
Deficiency unknown
Toxicity rare
Excrete excess in the urine

24. Maintaining Fluid Balance in the Body
Electrolytes: sodium, potassium, chloride
Maintain fluid balance
Transmit nerve impulses
Muscle contraction
Transport nutrients

25. Sodium (Na) Major positively charged ion in extracellular fluids
Functions
Regulating fluid balance
Regulating blood pressure
Transmitting nerve impulses
Contracting muscles
Helping nutrient transport

26. Sodium Consumption AI = 1,500 mg/day
Food sources: table salt and processed foods
UL for adults = 2,300 mg/day
Overconsumption can cause hypertension

27. DASH Diet Dietary Approaches to Stop Hypertension (DASH)
Helps lower sodium intake and increases potassium, calcium, and magnesium intake

28. DASH Diet

29. Potassium (K) Primary electrolyte within cells Functions
Regulating fluid balance
Acting as a cofactor for certain enzymes
Helping nutrient transport
Helping maintain electrical activity of the heart
May counter effects of excess sodium on blood pressure

30. Dietary Sources of Potassium

31. Potassium Deficiency Mild forms Severe depletion causes hypokalemia
Increase risk of hypertension, stroke, and heart attacks
Severe depletion causes hypokalemia
Usually from excessive fluid loss through vomiting, diarrhea, use of diuretics, or kidney disorders
Fatigue
Muscle weakness
Abnormal heart rhythms
Increased calcium excretion
Reduced insulin production

32. Potassium Toxicity Only from supplement misuse Symptoms
Low heart rate
Abnormal heart rhythm
Supplementation should be prescribed and monitored by a health-care provider

33. Chloride (Cl) Half of the mineral composition of table salt (NaCl)
Found primarily in extracellular fluids
Involved in fluid balance
Half of hydrochloric acid (HCl)
Abundant in the diet with sodium
Overconsumption increases blood pressure

34. Water (H20) Functions Regulates body temperature
Transports nutrients and oxygen
Lubricates joints
Present in mucus and saliva
Cushions tissues
Acts as a solvent
Removes waste

35. Water Balance in the Body
2/3 of water is intracellular
1/3 of water is extracellular
Waters moves by osmosis
Based on the concentration of solutes

36. Water Balance

37. Antidiuretic Hormone and Water Balance

38. Water Intake Recommendations

39. Water Intake Deficiency Excess water consumption without electrolytes
Dehydration
Nausea
Dizziness
Elevated temperature
Excess water consumption without electrolytes
Hyponatremia
Confusion
Nausea
Vomiting
Bloating
Swelling around the brain

40. Summary
16 essential minerals in the diet are inorganic elements supplied through food
Minerals in the diet are classified as major or trace, based on the amount required per day; major minerals include sodium, potassium, chloride, calcium, magnesium, phosphorus, and sulfur
Minerals have diverse regulatory and structural functions in the human body, including participation in chemical reactions, transmission of nerve impulses, maintenance of fluid balance, and support of the immune system
Bioavailability of the minerals we consume is affected by various factors, including nutritional status as well as the presence of binders, other minerals, and certain vitamins

41. Summary (Cont’d)
Sodium, potassium, and chloride are electrolytes that function in fluid balance, transmission of nerve impulses, and muscle contraction
Dietary intakes of sodium and potassium affect our risk of hypertension
Dietary Approaches to Stop Hypertension (DASH) diet includes strategies to reduce sodium intake and increase intake of foods rich in potassium, calcium, and magnesium
Calcium levels in the blood are regulated through a process called calcium homeostasis
Adequate calcium intake across the lifespan is important in the maintenance of bone density and the prevention of osteoporosis

42. Summary (Cont’d)
Water is an essential nutrient with critical roles in the body; among its many functions, water helps regulate body temperature, transports nutrients and oxygen to tissues, lubricates joints and mucous membranes, cushions tissues, and removes waste
Water makes up the greatest percentage of our body, both by weight and by volume, and is present in varying amounts in every tissue and organ
To maintain water balance in the body, intake of fluid from beverages, food, and water produced in metabolism must equal water output from urine, respiration, perspiration, and stools
Consuming inadequate or excess amounts of water can lead to health issues