Chapter 8 The Minerals and Water: A Functional Approach.

Chapter 8

The Minerals

and Water: A Functional

Approach

Ask yourself:

True or False:1. Water accounts for about 60 percent of an

adult’s body weight.2. Milk is necessary for children, but adults

can find replacements for it.3. It is generally harder for women than for

men to obtain diets that are adequate in iron.

4. Sodium is bad for the body and should be avoided.

5. When a person becomes deficient in iron, the very first symptom to appear is anemia.

6. Zinc is toxic in excess.7. Both too little and too much iodine in

the diet can cause swelling of the thyroid gland, known as goiter.

8. A diet high in salt is associated with high blood pressure in some individuals.

9. Osteoporosis is a disease that can affect men and women at any age.

10. Bone damage is associated with smoking cigarettes.

The Minerals

• Do not contribute calories.• Have diverse functions in the body and

work with enzymes to facilitate chemical reactions.

• Required in very small amounts.• Are inorganic compounds occurring

naturally in the earth’s crust.• Contribute to the building of body

structures.

Two Classifications of Minerals

The Major Minerals• Calcium• Phosphorus• Magnesium• Sodium• Chloride• Potassium• Sulfur

The Trace Minerals• Iodine• Iron• Zinc• Copper• Fluoride• Selenium• Chromium• Molybdenum• Manganese

Two Classifications of Minerals

• Major minerals Occur in large quantities in the body and

are needed daily in the diet in large amounts.

• Trace minerals Occur in minute quantities and are needed

in smaller amounts in the daily diet.

Be sure to study Table 8-1 A Guide to the Minerals

Good Sources of Minerals in the USDA MyPlate Food Guide

Minerals for Healthy Bones

• Calcium • Phosphorus • Magnesium • FluorideVitamins important in

healthy bone:• Vitamin C• Vitamin D• Vitamin K

Minerals for Healthy Bones

• Bones are made up of complex living tissue based on the protein collagen

• Crystals of calcium and phosphorus (and some other minerals) are deposited into this matrix

• Two forms:– Trabecular (lacy

portion)– Cortical (outer portion)

A Bone’s Life: Bone is living tissue that continuously remodels itself.

Lacy, spongy trabecular bone

Blood vessels supply bones withnutrients and oxygen vital fortheir health.

Hard, compact cortical bone

The bone marrow within bonesserves to produce new blood cells.

Peak bone mass occurs at ~30 years of age. Afterwards, bone loss starts to outpace bone deposition.

Minerals for Healthy Bones

Calcium• Bones store 99% of the body’s calcium, which

plays two roles: Supports and protects soft tissues. Serves as a calcium bank, providing calcium to

the body’s fluids.• About 1% is in body fluids Essential for nerve impulses, muscle contraction,

heartbeat, maintenance of blood pressure, & blood clotting.

• Calcium serves as a cofactor for several enzymes.

Cofactor A mineral element that, like a coenzyme, works

with an enzyme to facilitate a chemical reaction.

Calcium• Needed to support the growth of teeth and

bones.• A deficit during growing years and in

adulthood can contribute to osteoporosis.• Osteoporosis • Also known as adult bone loss; a disease in

which the bones become porous and fragile.– osteo = bones– poros = porous

Minerals for Healthy Bones

Reasons for Loss of Bone Density:• Poor calcium intake• Fluoride and/or vitamin D deficiency• Heredity• Abnormal hormone levels• Alcohol consumption• Some prescription medicines or other

drugs• Lack of exercise, especially weight-bearing

exercise

Minerals for Healthy Bones

Calcium Recommendations

Calcium appears in 3 classes of foods:

1. Milk and milk products2. Green vegetables3. A few fish and shellfish

• Milk and milk products tend to contain the most calcium.

Milk contains both vitamin D and lactose which enhance calcium absorption and promote bone health.

• Green vegetables and some other foods may contain binders which can decrease calcium absorption.

• Binders• In foods, chemical compounds that can

combine with nutrients (especially minerals) to form complexes the body cannot absorb. Examples are:Phytic acid: renders the calcium, iron,

zinc, and magnesium in certain foods less available than they might be otherwise.

Oxalic acid: also binds calcium and iron.

• A high fiber intake can also diminish calcium absorption.

Minerals for Healthy Bones

• Calcium-fortified foods are available for those who cannot take milk products.

• Milk allergy: the most common food allergy; caused by the protein in raw milk.

• Lactose intolerance: an inherited or acquired inability to digest lactose as a result of a failure to produce the enzyme lactase.

Phosphorus• Combined with calcium

to form calcium phosphate; gives rigidity to bones and teeth.

• Part of DNA and RNA; necessary for all growth; genetic code.

• Plays major role in energy production as a component of enzymes and B vitamins.

• Transports nutrients.

Minerals for Healthy Bones

Phosphorus is found in virtually all foods and the requirement is easy to meet. A high intake of phosphorus can interfere with calcium absorption.

Sources of Phosphorus

Minerals for Healthy Bones

Minerals for Healthy Bones

Magnesium• Acts in all cells of

muscle, liver, heart and other soft tissues.

• Helps relax muscles after contraction.

• Bone magnesium is a reservoir.

• Deficiency not likely but can occur in certain conditions.

Sources of Magnesium

Minerals for Healthy Bones

Fluoride:• Only a trace amount is found in the body but

its continuous presence is desirable:– Protects teeth from decay.– Makes bones of older individuals more

resistant to bone loss (osteoporosis).• Drinking water is the usual supply of fluoride

and is an effective means to prevent dental cavities.

Minerals for Healthy Bones

Minerals for Healthy Bones

Fluorosis Discoloration of the teeth from ingestion of too much fluoride during tooth development.

Alternatives to water fluoridation:Fluoride toothpastesFluoride treatments for teethFluoride tablets & drops

In some communities, thenatural fluoride concentration may be high.

Fluoridation in the United States

Minerals for Healthy Blood

• Iron • Zinc • Copper

All associated with hemoglobin

Minerals for Healthy Blood

Iron• The body’s oxygen carrier:

Bound into the protein hemoglobin in red blood cells.

Hemoglobin The oxygen-carrying protein of the

blood; found in the red blood cells.Iron helps transport oxygen from

lungs to tissues and thus aid the release of energy from fuels to do the cell’s work.

Iron• When the iron supply is too low, iron-deficiency

anemia occurs.

• Iron-deficiency anemia: a reduction of the number and size of red blood cells and a loss of their color because of iron deficiency.

• Symptoms of iron-deficiency anemia include:Weakness and/or fatigueApathyHeadaches Increased sensitivity to coldPaleness

Minerals for Healthy Blood

Two Forms of Iron:• Heme iron: Bound into iron-carrying

proteins like hemoglobin. Found in meat, fish, and

poultry. More reliably absorbed.• Nonheme iron: found in

plant and animal foods. Not as reliably absorbed.

You can combine foods to achieve maximum iron absorption--the heme iron in the meat and the vitamin C in the tomatoes in this chili help you absorb the nonheme iron from the beans.

Minerals for Healthy Blood

Minerals for Healthy Blood

Enhance iron absorption:

• Heme iron• Vitamin C

Interfere with iron absorption:• Foods containing phytic

acid (occurs in some fruits, vegetables, and whole grains)

• Tannins (occur in black tea, cola, coffee, chocolate, and red wine)

• Fiber—resulting in increased transit time of foods through intestines

Minerals for Healthy Blood

• Contamination Iron: Iron obtained from

cookware or soil can increase iron intake significantly.

• Iron Toxicity: Large amounts of iron

can be toxic.• Iron overload: a

condition in which the body absorbs excessive amounts of iron; tissue damage can occur.

Minerals for Healthy Blood

Minerals for Healthy Blood

Zinc• Found in every cell of the body and present in

enzymes that regulate:Cell multiplication and growth.Metabolism of protein, carbohydrate, fat, and

alcohol.Disposal of free radicals.

• Involved in utilization of vitamin A, taste perception, thyroid function, wound healing.Zinc’s role in preventing colds has been

inconclusive.

Zinc is highest in foods of high protein content. Two servings of animalprotein per day will generally provide most of the zinc needed daily.Excess zinc through supplementation should be avoided.

Sources of Zinc

Minerals for Healthy Blood

Zinc Deficiency:• Symptoms include: Night blindness Hair loss Poor appetite Susceptibility to

infection Poor wound healing Decreased sensitivity to

taste and smell Poor growth in children The Egyptian boy in this picture is 17

years old but he is only 4 feet tall

Minerals for Healthy Blood

Copper• A trace mineral involved in a variety of

metabolic and physiologic processes including:Making red blood cells.Manufacturing collagen.Healing wounds.Maintaining the sheaths around nerves.

• Good food sources include whole grains, nuts, seeds, legumes and shellfish

Minerals for Healthy Blood

Minerals for Energy Metabolism

• Iron • Zinc • Iodine • Chromium • Sulfur • Selenium

Chromium• This trace mineral works closely with the

hormone insulin to help cells take up glucose and break it down for energy.

• Good food sources include dark chocolate, nuts, mushrooms, asparagus and whole grains.

Minerals for Energy Metabolism

Sulfur• Present in some amino acids and all

proteins.• No recommended intake.• No known deficiencies unless the

person is protein deficient.

Minerals for Energy Metabolism

Iodine:• Part of thyroid hormone, which regulates body

temperature, metabolic rate, reproduction, and growth.

• Controls the rate at which cells use oxygen and energy.

• Present in soil in coastal areas of the country.• Iodized salt was introduced as a preventative

measure to prevent deficiency diseases.– A recent emergence of goiter in the U.S.

indicates the importance of continued use of iodized salt.

Minerals for Energy Metabolism

Minerals for Energy Metabolism

Iodine• Goiter • Enlargement of the

thyroid gland caused by iodine deficiency.

• Cretinism • Severe mental and

physical retardation of an infant caused by iodine deficiency during pregnancy.

Minerals for Energy Metabolism

• Amount in food reflects amount in the soil where plants are grown or animals are raised

• ½ teaspoon iodized salt meet the daily requirement

Minerals for Energy Metabolism

Selenium:• A trace mineral found in the soil.• Necessary for synthesis of thyroid hormone that

regulates body’s metabolic processes• Functions as part of the antioxidant enzyme

system that defends the body from free radical formation.

• Deficiency found in areas with little selenium in the soil

• Good sources include whole grains, meat, seafood, and fruits and vegetables

Water, Minerals, and Fluid Balance

• Water is indispensable for life and essential for health.

• Nutrient most needed by the body.

• A combination of hydrogen and oxygen atoms.

• Makes up part of every cell, tissue, and organ in the body.

• Accounts for about 60% of body weight.

Life begins in water

Water, Minerals, and Fluid Balance

150-lb Man

Carbohydrate30 lb

30 lb

90 lb

Fat

Water

MineralsVitamins

Protein

Minerals for Fluidand Electrolyte Balance

• Sodium • Chloride • Potassium• Phosphorus

Water, Minerals, and Fluid Balance

Fluid Balance• About 40% of the body’s water is inside the cell, about

15% is outside the cell, and the remainder is in blood vessels.

• Cells maintain water balance by pumping minerals across their membranes and water follows the minerals.

• Minerals used for this purpose are called ions or electrolytes.

Ions: electrically charged particles, such as sodium and chloride.

Electrolytes: compounds that partially dissociate in water to form ions; examples are sodium, potassium, and chloride.

Electrolytes• Sodium, potassium, and

chloride are examples of body electrolytes.

• Potassium, which is usually found in the fluids inside the cells, carries a positive charge.

• Sodium and chloride are usually found in the fluids outside the cells.

• Sodium carries a positive charge.

• Chloride carries a negative charge.

Water, Minerals, and Fluid Balance

Fluidinsidecells is rich inpotassium (K ).

Fluid outsidecells is rich insodium (Na )and chloride (Cl ).

Na+ Cl–

Na+ Cl–

Na+ Cl–

Na+ Cl–

Na+ Cl–

Na+ Cl–

• Maintaining healthy concentrations of electrolytes is vital to life so that cells can do their work such as:Nerve-to-nerve communicationHeartbeatMuscle contraction

• Electrolytes are lost in sweat, blood and urine.– Fluid losses must be replaced to

prevent dehydration and heat stroke.

Water, Minerals, and Fluid Balance

Sodium• Found naturally in many foods.• Component of sodium chloride (table salt), a food

seasoning and preservative.• The use of highly salted foods can contribute to

high blood pressure (hypertension) in those who are genetically susceptible.

• Hypertension: sustained high blood pressure.hyper = too muchtension = pressure

• Dietary Guidelines for Americans recommend consuming little sodium and salt and staying below the upper limit of 2300 mg of sodium per day.

Water, Minerals, and Fluid Balance

• In general, the more processed a food is, the more sodium it contains.– Up to 75% of salt in the U.S. diet has

been added by food processors.– The salt shaker adds only about 15% of

the total salt consumed daily.• Many whole foods are low in sodium

and high in potassium.

Water, Minerals, and Fluid Balance

Choose & Prepare Foods with Less Salt

• At the Supermarket:Read the Nutrition

Facts…Limit your intake of

cured foods & condiments

Cut back on your intake of prepared products

Buy fresh, natural foods more frequently

Choose & Prepare Foods with Less Salt

• At Home:Flavor foods with herbs, spices, etc…Cook without or with less saltRinse canned foodsConsult the DASH eating plan

• When Eating Out:Ask how foods are prepared and if possible,

ask them to not add saltMove the salt shaker awayLimit condimentsChoose fruits or vegetables instead of salty

snack foods

Sources of Sodium

Water, Minerals, and Fluid Balance

Potassium• Critical to maintaining the heartbeat. Sudden deaths that occur due to fasting, severe

diarrhea, or severe vomiting are thought to be due to heart failure due to potassium loss.

• As the principal positively charged ion inside body cells, potassium plays a major role in maintaining water balance and cell integrity.

• Potassium deficiency is dangerous. Potassium is lost in dehydration. Some diuretics taken to increase water loss also

cause loss of potassium. Diuretics Medications causing increased water excretion.

• dia = through ouron = urine

Water, Minerals, and Fluid Balance

• Some physicians will prescribe a potassium supplement for people taking diuretics.

• Potassium supplementation should be medically supervised and never self-prescribed.Toxicity is the concern rather than a

deficiency

Water, Minerals, and Fluid Balance

• The relationship of potassium and sodium in maintaining blood pressure is not clear.

• Increasing potassium in the diet can promote sodium excretion and may lower blood pressure.

• A lifelong intake of low-sodium and high-potassium foods protects against hypertension.

Water, Minerals, and Fluid Balance

• A dietary deficiency of potassium is unlikely but high-sodium diets that are also high in processed foods and low in fresh fruits and vegetables can make it a possibility.

Sources of Potassium

Water, Minerals, and Fluid Balance

Chloride• This negative ion accompanies sodium in

the fluids outside the cells.• It crosses membranes freely and can also

be found inside the cells.• Helps in maintaining acid–base balance.• Nearly all dietary chloride comes from salt

or sodium chloride.

Water, Minerals, and Fluid Balance

Diet & Blood Pressure

RISK FACTORS• Obesity• Family history• Race (African

American)• Age (increased)• Excess alcohol

consumption• Sedentary

lifestyle

Hypertension has been called a “silent killer” because it cannot be felt and may go undetected for years.

Are Your Numbers Up?

• Diagnosis of hypertension requires at least two elevated readings.

• Individuals with prehypertension are at increased risk for progression to hypertension and should make lifestyle changes such as:Losing weightLowering sodium intakeDecreasing alcohol consumption to moderate

amountsExercising more

Diet & Blood Pressure

An Eating Plan to Reduce High Blood Pressure

• DASH Diet: Dietary Approaches to Stop Hypertension• The DASH diet eating plan has been effective in

reducing blood pressure.• Choose low-fat dairy products, smaller portions of

meat, plenty of fruits and vegetables, and ample servings of high-fiber, whole-grain products.

This diet is high in fruits, vegetables, whole grains, and low-fat dairy products.

The diet is lower in total fat, saturated fat, and cholesterol.

May reduce risk for heart disease, hypertension, diabetes, osteoporosis and cancer.

Tips to Reduce Hypertension Risk

1. Adopt an eating pattern rich in fruits, vegetables, legumes, and low-fat-dairy products—similar to the DASH diet—with reduced saturated fat content.

2. Maintain a normal weight. Lose weight if you’re overweight; even losing just a few pounds can reduce blood pressure if you’re overweight.

3. Keep your sodium intake at or below recommended levels—not more than 2,300 milligrams a day.

4. Pursue an active lifestyle: Walk briskly, swim, jog, cycle, or other moderately paced aerobic activities. Aim for at least 30 minutes of activities daily.

5. If you drink, use moderation—no more than one drink a day for women, and no more than two drinks a day for men.

6. Don’t smoke. Cigarette smoking raises blood pressure and increases risk for heart disease.

OsteoporosisThe Silent Stalker of the Bones

• Women generally have less bone mass than men. • Women typically have lower calcium intakes than men.• Women more often use weight-loss diets, which tend to be

low in calcium and lead to bone loss.• Bone loss begins earlier in women because of women’s

different hormonal makeup, and the loss is accelerated at menopause, when their protective estrogen secretion declines.

• Pregnancy and lactation decrease the calcium reserves in bones whenever calcium intake is inadequate.

• Women live longer than men, and bone loss continues with aging.

Risk Factors

• Age (older)• Gender (female)• Age-Related Decline in Hormones• Abnormal absence of menstrual periods• Family History• Race/Ethnic background (Caucasian, Asian) • Body build (thin, small framed, petite)• Sedentary Lifestyle• Smoking and Alcohol• Medical Conditions (often due to prescription

meds)• Lack of a bone healthy diet including calcium,

vitamin D and other nutrients

Prevention

• Maximize peak bone mass and be vigilant about keeping the bones well supplied with calcium.

• Consume alcohol only in moderation, if at all, and avoid cigarettes altogether.

• Exercise regularly, because exercise can reduce the risk of developing osteoporosis by making bones stronger and increasing their ability to absorb calcium.

• For women at or nearing menopause, talk to your health care provider about bone loss after menopause