1. Chapter 8
Minerals

2. Key Concepts
The human body requires a variety of minerals to perform numerous metabolic tasks
Inorganic substances
Minerals = elements

3. Minerals Classes of minerals
Major minerals (recommended intake >100 mg/day)
Trace elements (<100 mg/day)
Functions of minerals: Tissue building & metabolism
GROWTH & MAINTENANCE
What are the four fundamental elements that make up most living matter? Hydrogen, carbon, oxygen, and nitrogen
Ask students to name a trace element or a major mineral.
Explain that unlike carbohydrates, proteins, and fat, minerals do not require a great deal of mechanical or chemical digestion before absorption.

4. Major Minerals Calcium >100mg/day Phosphorus Sodium Potassium
Chloride
Magnesium
Sulfur

5. Calcium Functions Bone and tooth formation Muscle contraction
Nerve conduction
What does the absorption of dietary calcium depend on? The food form and the interaction of three hormones that directly control absorption, along with indirect metabolic stimuli from the estrogen hormones
Where can most of the body’s calcium be found? Bones and teeth
Explain that calcium in the bones acts as a pool for calcium that can then be used to maintain blood calcium levels.
Calcium is essential for muscle contraction.

6. Calcium, cont’d Requirements Deficiency states
1000 mg/day
Deficiency states
Osteoporosis
Toxicity symptoms – kidney stones
Food sources
Milk is the major food source
Green vegetables, fish with bones, fortified food
What can reduce the risk for developing osteoporosis? Diet, especially during childhood and adolescence, physical activity including weight-bearing exercises, not smoking
How many in the class drink milk or eat dairy products?
Name some of the green vegetables that are good sources of calcium. Broccoli, spinach, kale

7. Osteoporosis
Left side: normal, healthy bone
Right side: osteoporotic bone
Which bone looks easier to break?
Figure information:
Normal bone (left) versus osteoporotic bone (right).
From Mahan LK, Escott-Stump S: Krause’s food & nutrition therapy, ed 12, Philadelphia, 2008, Saunders.
Copyright © 2009, by Mosby, Inc. an affiliate of Elsevier, Inc. All rights reserved.

8. Phosphorus Functions Bone and tooth formation, works with Calcium
Energy metabolism (releases energy from CHO, fat, protein)
Maintain proper acid-base balance
What other mineral is essential for bone and tooth formation? Calcium
DNA has phosphorous in its backbone.

9. Phosphorus, cont’d Requirements
700 mg/day
Deficiency states – rare, widely available in foods
Toxicity: usually with renal disease (hyperphosphatemia)
Food sources
Milk, milk products, fish, eggs
If a phosphorus deficiency does develop, what are the characteristics? Weakness, loss of appetite, fatigue, pain
Is it difficult for most Americans to meet the requirement for phosphorus?

10. Sodium Functions Maintenance of water balance Acid-base balance
Muscle action & transmission of nerve impulses
What is the main function of sodium? Water balance
Explain that sodium is needed for glucose to be absorbed.

11. Sodium, cont’d Requirements Deficiency – rare Toxicity
Recommended g/day
*usual intake = 3500 mg/day
Deficiency – rare
strenuous exercise/diaphoresis, excess water intake: can lead to acid-base imbalance, muscle cramps, neuro changes from low sodium (hyponatremia)
Toxicity
Hypertension, especially w/ kidney disease
Food sources - Table salt, cured meat, canned soups, processed food
Excess sodium can lead to what chronic disease? Hypertension
What is the main dietary source of sodium? Table salt
What is salt sensitivity?

12. Potassium Functions Water balance Blood pressure Muscle action
Insulin release from beta cells (pancreas)
Explain that sodium and potassium work with each other to maintain water balance. Mention that sodium is extracellular and potassium is intracellular.
Does potassium raise or lower blood pressure?

13. Potassium, cont’d Requirements – no specific RDA
*Amer. diet low 2-3 g/day
Deficiency – hypokalemia – muscle cramps
Toxicity – hyperkalemia, can cause severe heart arrythmias, caution w/ kidney disease
Food sources
Fruits, vegetables, whole grains, fresh meats
Oranges, bananas, tomatoes, potatoes, broccoli, leafy greens
FOOD SOURCES – ORANGES, BANANAS, POTOTOES, TOMATOES, BROCCOLI, LEAFY GREENS – LOTS OF POTASSIUM
LOST DURING COOKING AND BOILING
When are potassium deficiencies more likely to occur? During clinical situations such as prolonged vomiting or diarrhea, during use of diuretic drugs, during use of hypertension drugs, as a result of severe malnutrition, or after surgery
What is the result of extremely high potassium levels? Fatal arrhythmia
Do most Americans meet the AI for potassium each day?

14. Chloride Functions Digestion
Key element in hydrochloric acid secretion
Respiration – works with CO2 in maintaining acid base balance
Emphasize that chloride is needed for digestion of all foods through hydrochloric acid.

15. Chloride, cont’d Requirements – no specific RDA
AI: 2.3 g/day
Deficiency – rare, excessive vomiting may result in acid/base imbalance
Food sources
Table salt
Sea salt *both contain NaCl
What is the primary reason for chloride deficiency? Excessive fluid losses through vomiting, which leads to metabolic alkalosis
The only known development of toxicity is through dehydration.

16. Magnesium Functions General metabolism Protein synthesis
Found in all body cells
Works with 300+ enzymes to produce energy
Protein synthesis
Activates amino acids
Muscle action – aids w/ nerve impulses, stimulation of muscle contraction
Where in the body is magnesium found? In all body cells; it has widespread metabolic functions.
Review what a catalyst is. Why are catalysts important?
Discuss basal metabolic rate and how magnesium deficiency could influence it.

17. Magnesium, cont’d Requirements
~300 to 400 mg/day (increases w/ age and preg)
Deficiency – rare, may be seen w/ vomiting & starvation, can cause muscle cramping/weakness
Toxicity – rare, caution w/ kidney disease
Food sources - Nuts, soybeans, cocoa, seafood, peas, green vegetables
What are some of the deficiency symptoms? Muscle weakness and cramps, hypertension, and blood vessel constriction in the heart and brain
Which individuals are at greater risk for developing magnesium toxicity? Those with renal insufficiency
Which sources are relatively poor sources of magnesium? Most fruits, except bananas; milk; meat; and fish .

18. Trace Elements Iron Iodine Zinc Selenium Fluoride Copper Manganese
Chromium
Molybdenum
Cobalt
Boron
Vanadium
Nickel
<100 mg/day needed.

19. Iron Essential for life, but dangerous when in excess Functions
Hemoglobin synthesis (Hg carries O2 to cells)
General metabolism
Proper glucose metabolism
Antibody production
Collagen synthesis
Conversion of beta-carotene to vitamin A
70% of the body’s iron occurs where? In red blood cells
Iron is most well known for its role in hemoglobin and therefore its essentiality in oxygen transport.

20. Iron, cont’d Requirements (increase w/ age and pregnancy)
8 to 11 mg/day for males
8 to 18 mg/day for females
Deficiency states
Anemia (decreased RBC’s)
Toxicity – can be fatal
Hemochromatosis (iron overload – can cause organ damage)
Food sources: meats, eggs, fortified cereals, liver, better absorbed w/ Vit C
What is one clinical test to determine iron-deficiency anemia? Hemoglobin levels, hematocrit
Why do women need more iron than men? Menses
Explain that hemochromatosis is a genetic condition enabling the body to retain more iron than needed.
Discuss the signs and symptoms of iron-deficiency anemia.

21. Iodine Functions Requirements
Participation in thyroid gland’s synthesis of thyroxine, hormone required for metabolism
Requirements
150 mcg/day (minimum 50-75)
What is the function of thyroxine? Regulates metabolic rate
Where is the thyroid gland located?

22. Iodine, cont’d Deficiency states Toxicity symptoms - rare Food sources
Goiter (enlarged thyroid gland)
Cretinism (dwarfism, MR – due to lack of iodine during pregnancy)
Hypothyroidism (wt. gain, hair loss, dry skin, cold intolerance)
Hyperthyroidism – Graves disease (wt.loss, tremors, nervousness/restless)
Toxicity symptoms - rare
Food sources
Iodized table salt, seafood
What is the difference between hypothyroidism and hyperthyroidism? Low t4 vs. high t4
Cretinism results from a mother eating insufficient amounts of iodine during fetal development.
What are the characteristics of cretinism? .

23. Goiter
Describe the process of how iodine deficiency leads to goiter.
Figure information:
B, From Swartz MH: Textbook of physical diagnosis, ed 5, Philadelphia, 2006, Saunders.
Copyright © 2009, by Mosby, Inc. an affiliate of Elsevier, Inc. All rights reserved.

24. Zinc Functions Requirements Important during growth & pregnancy
Important for immune system
Requirements
11 mg/day for males
8 mg/day for females
Zinc is especially important during what growth periods? Pregnancy, lactation, infancy, childhood, and adolescence
Who reported the lowest zinc intake on the National Health and Nutritional Examination Survey? Children aged 1 to 3 years, adolescent girls, and persons older than 71 years

25. Zinc, cont’d Deficiency Toxicity – N/V w/ overuse Food sources
Poor wound healing, hair loss
Impaired taste and smell
Dwarfism, impaired sexual maturation
Toxicity – N/V w/ overuse
Food sources
Meat, seafood, legumes, whole grains
Zinc is often supplemented for patients with open wounds.

26. Selenium Functions Requirements Food sources
Antioxidant, aids in protection from free radicals
Requirements
RDA: 55 mcg/day
Brittle hair and nails w/ deficiency
Food sources
Seafood, kidney, liver; depends on soil content
Selenium functions with specific proteins as an essential part of an antioxidant enzyme, glutathione peroxidase, which protects cells and their lipid membranes from oxidative damage.
It also functions as a part of the protein center of teeth and participates in the regulation of thyroid hormone action and vitamin C activity.
A mild selenium deficiency can have what effect? It may decrease a person’s ability to fight infection. Severe deficiency may put individuals at risk for certain types of cancer.

27. Other Trace Elements Fluoride Functions by preventing dental carries
Prevent cavities, hardens tooth enamel
Important for dental health
What is fluorosis?
When is it critical to watch fluoride intake so fluorosis does not occur?
Explain why copper is called iron’s twin. They have many of the same functions.
Manganese toxicity can result from mining.

28. Mineral Supplementation
Life cycle needs
Pregnancy and lactation - need more Mg, Iron, Zinc, Iodine, Selenium
Adolescence – more Ca and Phos
Adulthood – mineral supp not needed, balanced diet is more important
Clinical needs
Iron-deficiency anemia (adol, preg)
Zinc deficiency (vegetarians at risk)
Special needs during growth periods and in clinical situations may require individual supplements of specific major minerals or trace elements.
Plant foods have little zinc – vegetarians at risk – sources of zinc = meat, seafood
Ask students to name five high-risk groups that may need to supplement their diet and explain why. Adolescent girls on poor diets, low-income adolescent boys, athletes, vegetarians, and elderly persons on poor diets

29. Applying Knowledge
The camp nurse gives a talk to the camp staff about the signs of fluid volume deficit. She encourages the counselors to be sure the campers drink fluids throughout the day. One counselor responds, “Oh, that’s no problem. The kids guzzle flavored ice tea all day long.” How should she respond?
Copyright © 2009, by Mosby, Inc. an affiliate of Elsevier, Inc. All rights reserved.