Ch. 9 Minerals

bioavailability of minerals

1. Bioavailability of minerals varies. - In general, minerals in animal foods are more easily absorbed than minerals in plant foods.

copper: functions

Copper is needed 1. to form hemoglobin 2. and collagen 3. and assists in many other body functions. - Interacts with iron in energy-releasing reactions - 4. Is part of a family of major antioxidant enzymes known as superoxide dismutases • they are proteins cofactored with copper and zinc, or manganese, iron, or nickel. • Among the most abundant proteins in the body

maintaining normal blood Ca levels (2)

1. Thyroid gland - Secretes calcitonin when blood calcium is too high • Stimulates osteoblasts (bone building) 2. Parathyroid glands - Secrete parathyroid hormone (PTH) when blood calcium is too low • Stimulates osteoclasts (bone breaking)

major minerals: names (7)

1. calcium 2. phosphorus 3. potassium 4. sulfur 5. sodium 6. chloride 7. magnesium

Trace minerals: names (7)

1. iodine 2. iron 3. zinc 4. selenium 5. fluoride 6. chromium 7. copper

trace minerals: names (5)

1. iron 2. zinc 3. copper 4. iodine 5. many more

electrolytes

- Compounds (minerals) that partially dissociate (dissolve) in water to form ions

sodium: functions (3)

- Major positively charged ion in extracellular fluid - Conducts nerve impulses - Involved in transporting glucose and amino acids into cells

potassium: functions

- Major positively charged ion in intracellular fluid - Needed for nerve impulses, contracting muscles, and kidney function - Potassium-rich diets may reduce blood pressure

bone development & maintenance (2)

1. Bones are constantly remodeling in response to physical stress. 2. • Remodeling involves two types of cells: Osteoclasts — tear down bone tissue where there is little stress Osteoblasts — add bone to where there is more stress

calcium supplements

1. Calcium Supplements - Calcium carbonate (hardly absorbed) or citrate (better) with vitamin D (D enhances absorption)

Minerals: overall (3)

1. Carbon atoms in carbohydrates, fats, proteins, and vitamins combine with oxygen to produce carbon dioxide, which goes into the air. 2. Hydrogens and oxygens form water, and along with body water, this evaporates. 3. Ashes are about 5 pounds of minerals . -About 3/4 is calcium and phosphorus • Mostly in the bones -Less than a teaspoon of iron • Most in hemoglobin protein of RBCs

chromium: general & sources

1. Chromium works with the hormone insulin to control blood glucose concentrations. - Deficiency causes a diabetes-like condition (but not diabetes!) - Extra chromium will not build muscle or melt off body fat! 3. Chromium is present in a variety of unrefined foods - liver, whole grains, nuts, and cheeses are good sources. 4. It is estimated that percent of U.S. adults consume less than the recommended minimum intake of 50 micrograms a day. - Easily lost during food processing

copper: deficiency, sources & UL

1. Deficiency is rare. - Excess zinc interferes with copper absorption - Disturbs growth, metabolism, immunity and blood flow 2. Good food sources include: organ meats, seafood, nuts, and seeds. - Even copper plumbing is a source - U.S. intakes adequate 3. UL is 10 milligrams per day

calcium intakes & UL

1. Dietary Adequacy - AI 1000 to 1200 mg/d (adults) 2. Calcium Toxicity - UL = 2500 mg/d (hypercalcemia)

regulating iron (2)

1. Digestive tract absorbs - 5-15% of iron - Only ~5% of iron from enriched grains is absorbed 2. Most iron stored as ferritin in the liver - Iron from broken down (& stored as ferritin) hemoglobin is "recycled" and incorporated into new hemoglobin

fluoride sources

1. Fluoride is added to drinking water to lessen tooth decay -This is the usual source of flouride, but watch for mouthwash, infant formula, and supplements 2. Flouride is added to some toothpastes 3. To prevent fluorosis • Discoloration of the teeth from too much flouride during tooth development - young children should not swallow toothpaste - Fluorosis is irreversible, and does not occur after teeth have formed

iodide deficiency (2)

1. Goiter • Characterized by enlarged thyroid gland • Common before advent of iodized salt in areas where iodine content of soil was poor 2. Cretinism • Irreversible condition affecting infants born to women who were iodide deficient during pregnancy

major minerals: definition

1. Major minerals = 7 minerals - Present in larger quantities than trace • Amounts greater than 5 grams

water follows salt

1. Major minerals form salts that dissolve in body fluids; the cells direct where the salts go; and this determines where the fluids flow because water follows salt. 2. The body controls the flow of water by moving electrolytes from one place to another - Cells expend energy to move electrolytes across their membranes - Water follows the electrolytes as the system tries to maintain equilibrium 3. This accomplished by special transport proteins located in the cells plasma membrane, known as p

chromium functions (2)

1. May enhance insulin's action on cell membranes • 2. "Holds the door open" for glucose entry into cells

sources of minerals (3)

1. Most foods contain minerals (b/c they need it survive) 2. Animal foods generally contain higher amounts of minerals than plant foods. 3. Processing foods often reduces mineral contents.

fluoride: general (4)

1. Not essential to life 2. But fluoride stabilizes bones and makes teeth resistant to decay. - Bones and teeth are made from Hydroxyapatite (calcium and phosphorous). Flouride replaces a little with Fluorapatite during formation • a mineral that makes bones and teeth even harder 3. Excess fluoride discolors teeth; large doses are toxic. 4. There is no support that fluoridated water causes cancer

chloride (5)

1. Principle food source - table salt, NaCl 2. Chloride is the body's major negative ion It is responsible for: 3. - stomach acidity, Hydrochloric acid in stomach 4. - Crucial for fluid balance/assists in maintaining body chemistry • Follows sodium in fluid outside of cells • Acid-base balance & Electrolyte balance 5. No known diet lacks chloride.

sulfate: functions, intakes, deficiencies

1. Roles in proteins. it's located in - 2 amino acids have S-containing side group 2. No recommended intake 3. Deficiencies are unknown......

sulfate: general

1. Sulfate is the oxidized form of sulfur as it exists in food and water. - Affects acid-base balance and electrolyte balance as sulfate ion -SO4-2 • Epsom Salts are MgSO4 2. Used to synthesize sulfur-containing body compounds. - Example: Some proteins have their shapes rigidly maintained by -S-S- bonds between certain amino acids • Curly hair has many of these bonds

other sources of minerals (2)

1. Tap water -"hard " water contains a variety of minerals, including calcium, sulfur, copper, iron, and zinc. -Most public water supplies provide fluoride. 2. Dietary supplements -A daily multiple vitamin and mineral supplement is generally safe for healthy people. -Supplements of single minerals may be toxic, if taken in excess.

Major mineral: calcium

1. The most plentiful mineral in human body - > 99% is in bones and teeth - ~ 1% is in extracellular fluid 2. Healthy adults absorb ~25% of calcium - Absorption increases during growth - Absorption decreases with advanced age, vitamin D deficiency, diarrhea, and high intakes of phosphorus, oxalic acid, or phytic acid

iron toxicity

1. Upper Limit (UL) = 45 mg/d • May occur in children <6 yrs due to supplement overdose - Signs include vomiting and diarrhea, progressing to coma and death

6 possible essential minerals

1. arsenic 2. boron 3. lithium 4. nickel 5. silicon 6. vanadium

properties of water

1."Universal" Solvent - water will dissolve many substances 2. Hydrophilic - Attracts water. - Usually ionic (minerals) or polar substances (a polar molecule dissolves in water) 3. Hydrophobic - Cannot attract water. - Usually non-polar substances 4. A solution contains solutes dissolved in a solvent (usually water).

osteoporosis: definition

A chronic disease characterized by low bone mass and reduced bone structure - Among people over age 50, ~10 million have osteoporosis and 34 million are at risk. - Anestimated1.5million Americans have an osteoporosis- related fracture each year.

selenium intakes

Adequacy • Adult RDA = 200 mcg/d • Most Americans meet RDA

zinc intake

Adequacy • Adult RDA ranges from 8 to 13 mg/d • Children between 6 to 11 yrs at risk of deficiency

anemia

Anemia impairs oxygen transport in blood.

reducing risk of osteoporosis (2)

Begin early in life with: - Proper diet • Follow MyPyramid - Regular exercise • Weight bearing exercise strengthens bones (low-impact aerobics, basketball, running, walking, tennis)

mineral intakes

Many minerals have a narrow range of safe intake. As a result, it is relatively easy to consume a toxic amount, especially by taking supplements that only contain a particular mineral.

magnesium sources

green pigment in plants, spinach, leafy green vegetables, whole grains, beans, nuts, seeds & chocolate and milk and some meats

zinc sources

seafood meat, whole grains

zinc toxicity (3)

• Upper Limit (UL) = 40 mg/d • May reduce HDL cholesterol level • >100 mg/d results in diarrhea, cramps, vomiting, and depressed immune system (colds)

selenium toxicity

• Upper Limit (UL) = 400 mcg/d • Known as selenosis

chromium sources

• Widely distributed in foods Chromium is present in a variety of unrefined foods - liver, whole grains, nuts, and cheeses are good sources.

cofactor

an ion or molecule that catalyzes chemical reactions

iron: sources

beef, fish, poultry, whole grain & enriched breads and cereals Not milk

osteoclast

bone breaking tear down bone tissue where there is little stress

osteoblasts

bone building add bone to where there is more stress

sources of Ca in food

fluid milk, yogurt, cheese, broccoli, leafy greens (kale, collard, turnip, bok coy & mustard greens), sardines, tofu (made with calcium sulfate), almonds -plant foods not as bioavailable as milk & milk products

potassium sources

fresh fruits, fruit juice, vegetables, milk, whole grains, dried beans

hemoglobin

iron-containing protein in RBC that transports oxygen to tissues and some CO2 away from tissues

myoglobin

iron-containing protein in muscle cells that controls oxygen uptake from RBC

selenium sources

meat, eggs, fish, seafood, whole grains

zinc: functions (5)

• A component of hundreds of enzymes and other proteins. • Wound healing • Normal of taste and smell • DNA synthesis • Immune function

Calcium functions in order of importance (7)

• Bone formation and maintenance • Structural component of teeth • Muscle contraction • Blood clot formation • Nerve impulse transmission • Cell metabolism • May help control blood pressure and immune functioning

what contributes to osteoporosis? (7)

• Consuming excess protein, sodium, and caffeine, especially when calcium intake is low • Excessive alcohol consumption • Smoking cigarettes • Family history of osteoporosis • Menopause • Prolonged bed rest or physical inactivity • Certain medications

sodium deficiency

• Deficiency - May occur when > 2 to 3% of body weight is lost through sweating

blood pressure: diastolic

• Diastolic pressure — pressure when ventricles relax between contractions

magnesium intakes

• Dietary Adequacy - Adult RDA = 310 to 420 mg/d

iron: functions

• Iron is a component of hemoglobin and myoglobin. • Hemoglobin — iron-containing protein in RBC that transports oxygen to tissues and some CO2 away from tissues • Myoglobin — iron-containing protein in muscle cells that controls oxygen uptake from RBC • Iron is involved in energy generation and immune function.

selenium deficiency

• May occur with severe digestive tract conditions

selenium functions (2)

• Part of several proteins called selenoproteins • Many selenoproteins are antioxidants • May reduce risk of certain cancers

iron: intakes

• RDA 1. Women = 18 mg/d iron • Most females from ages 14 to 50 yrs have low intakes. 2. Men = 8 mg/d • Most males >age 9 yrs have adequate intakes.

magnesium deficiency

• Rare among healthy Americans • Most likely in girls between 14-18 yrs of age

iodide functions (3)

• Required for normal thyroid function and production of thyroid hormone • Thyroid hormone controls metabolic rate. • In U.S., some table salt is fortified with iodide to prevent deficiency.

magnesium toxicity

• Results from ingesting excessive laxatives, antacids, or dietary supplements

sodium toxicity

• Toxicity - UL = 2300 mg/d • Average intake is ~3400 mg/d. - High sodium intakes associated with increased risk of hypertension

iodide toxicity

• UL = 1.1 mg/d • May result in enlargement of thyroid gland

Minerals: Basic concepts = What are minerals? (4)

•Elements in Earth's rocks, soil, and natural water sources. • About 15 (25) mineral elements are essential nutrients. • Classified as micronutrients because they are required in mg or mcg amounts. • Minerals cannot be destroyed, but they can be lost from foods.

sodium & hypertension

Hypertension - condition characterized by persistently elevated blood pressure - Affects ~27% of American adults - Hypertension increases risk of: • Heart disease • Stroke • Kidney failure

hereditary hemochromatosis

Iron Overload: Common hereditary disorder resulting in excess iron absorption

Minerals & rocks

Mineral • any naturally occurring solids that is ... • An element or inorganic compound ... • And usually has a crystalline structure Rock • any natural combination of minerals that make up a part of the earth's crust

sodium: intakes

Only ~ 180 mg sodium required per day - AI = 1500 mg/d • AI for sodium does not apply to those who perspire heavily

magnesium: functions

Participates in >300 reactions • Roles the body include: - Regulation of muscle and nerve function - Maintenance of strong bones - Strengthening the immune system

blood pressure: systolic

Systolic pressure — maximum blood pressure within arteries when ventricles of the heart contract

sodium: general

Table salt = sodium + chloride salt = - 1 tsp salt supplies 2325 mg sodium

Trace minerals: definition

Trace minerals - - Present in smaller quantities than major • Amounts less than 5 grams

pumps: Na & K

Using the Sodium- Potassium Pump most body cells maintain the proper electrolyte balance by pumping sodium out of the cell and potassium into the cell - 3Na+ out, 2 K+ in - cells like high K+ inside - cells like high Na+ outside

safety & sources of drinking water

Water is practically a universal solvent : it dissolves almost anything it encounters to some degree. - Hundreds of contaminants have been detected in public drinking water

zinc deficiency (2)

- Zinc deficiency often occurs in people with chronic digestive tract problems and exclusively breastfed infants. - Associated with delayed sexual maturation and growth retardation

salts

- ions held together - Compounds (minerals) composed of charged particles, known as Ions - charged particles • Example: NaCl or sodium chloride - table salt - Na+ and Cl- = salts

minerals: major vs. trace

1. About 25 elements are essential to life 2. Four of these make up about 96% of the weight of the human body (CHNO) 3. Trace elements occur in smaller amounts

potassium intakes

Dietary Adequacy - AI = 4700 mg/d • Most Americans consume ~2700 mg/d

iodide intake

Dietary Adequacy • Adult RDA = 150 mcg/d

chromium dietary, deficiency & toxicity

Dietary Adequacy — most diets are adequate Deficiency — causes impaired glucose tolerance Toxicity — not known Chromium picolinate may damage DNA, but more research is needed.

Why are minerals necessary? (7)

Diverse roles, including: -Structural components of tissues (ex. bone) -Ions dissolves in fluids - Blood clotting (ex. Ca ions) - Fluid balance - Acid-base balance - Cofactors in chemical reactions - Part of certain enzymes and hormones