Transcript Chapter 12 and 13

Chapter 12
Water video
Water And The
Major Minerals
Water
• Most abundant substance in the body
• An average healthy adult is about 60
percent water
• Muscle tissue is approximately 65 percent
water
• Fat tissue is about 10 – 40 percent water
• Males have higher body water (59 vs. 52%
in women)
• Athletes have more body water then
sedentary individuals
Water
What does water do in the body?
• The universal solvent and a transport
medium
• Water plays a key part in carrying nutrients to
and removing wastes from the cells
• Water helps to maintain body temperature
by absorbing and releasing heat
• Lubricant and protective cushion
• Water is part of the blood and the fluid that
bathes the body cells
A developing fetus is cushioned in a sac of watery amniotic fluid to protect
it from physical harm during pregnancy
Water
Water balance and maintenance
• When the amount of water consume is
equal to the amount that you lose daily,
you are in water balance
• When you are not in water balance, you
may be taking too much or too little water
Water
• Water Loss:
– Lose water through kidneys, large intestine,
lungs and skin
– Insensible loss is water that is lost daily
through routine respiration and evaporation off
the skin up to 1 quart daily
• How to replenish water loss:
– beverages and foods
– A small amount of water can be generated
during metabolism
• Losing too much water can cause
dehydration
– Consuming too much water can cause
hyponatremia (low sodium level) may result in
death
Water
Water requirements are based on:
• Body weight, gender
– Adult female require an average intake of 9
cups of water
– Adult male require about 13 cups of water
• physical activity
• air temperature
• diet
water sources:
• Water
• most fruits and vegetables contain up to
90% water
Health Effects of water
• Meets body’s fluid needs
• Protect the bladder against
cancer by diluting urine
• Protect against kidney stones,
prostate cancer, and breast
cancer
Water
Types of water
• Mineral water – from underground source,
contains specific amount of naturally occurring
minerals and trace element
• Spring Water (well water) – flows from
underground to the surface naturally, water is
collected at the spring
• Sparkling water – spring water with carbon dioxide
gas. Do not have adhere to FDA standards for
bottled water it is consider a soft drink
Water
Types (cont’d)
• Distilled water – water that has been
boiled and processed to remove most
contaminants
• Flavored water – water that has flavor
such as lemon or lime added, may also
contain sugar and calories
• Vitamin Water – Water that has vitamins
added to it. May also contain sugar and
calories
Bottled vs. Tap Water
Bottled water
• Cost ~ $1.00 - ~4.00 per gallon
• Generally safe
• Some are not tested for
contaminants
• Only bottled water sold across
state lines are regulated by the
FDA
• More convenient
• May taste better
Water video
Tap water
• Cost less than 1 penny per
gallon
• Regulated by the EPA, state,
and local regulations
• Consumer have access to
water quality reports
• EPA requires that the public be
notified it water quality does
not meet standards
• Available at the faucet
• Contains fluoride to prevent
tooth decay. Most bottled
water do not contain fluoride
The Minerals
• Inorganic elements
• Major minerals are essential
nutrients found in >5g in the body
• Found in both plant and animal foods
• Minerals, like vitamins are part of
enzymes
• Work with your immune system
• Play a valuable role in structural
growth
The Minerals
• Absorption depends on bioavailability
– the degree to which nutrient is
available for absorption by the body
• Nutrient interactions is common e.g.
spinach is a source of calcium and
oxalates
• Divided into two categories – major
and trace minerals
Sodium
What are sodium and salt?
• Sodium is an electrolyte in the body
• Most sodium is in the blood and the
fluid surrounding the cells
• About 90% of the sodium we
consume is in the form of sodium
chloride
Sodium
• Functions in the body
–Regulate fluid balance
–Transport substances such as
amino acids across cell membranes
–Act as preservative and enhance
flavor of food e.g. Monosodium
Glutamate (MSG) used to enhance
food flavor in Asian cuisines
Sodium balance in the body
• The amount of sodium in the body is maintained
at a precise level
• When the body needs more, the kidneys
decrease the amount that is excreted in urine
• Likewise when you take too much, the kidneys
increase the amount that is excreted
• Smaller amounts of sodium are lost in the stool
and daily perspiration
Sodium
• Sodium is widely available in foods
• 77% of American's consumption of
sodium is from processed foods.
– 1 cup of fresh tomato has 11 mg of
sodium vs. 355mg from canned tomato
• 12% from foods that naturally
contain sodium
• 5% is added during cooking
• 6% used to season foods at the table
Sodium
Sodium Recommendation
• 1500 mg/day (19-50 yr)
• 1300 mg/day (51-70 yr)
• 1200 mg/day – (>70 yr)
• Upper limit 2300 mg/day
• Americans consume over
3,400mg daily
Sodium
Too much sodium
• There is a direct relationship
between sodium and blood pressure
• As a person’s intake of sodium
increases so is their blood pressure
known as hypertension
– increases risk of heart disease
– Stroke
– Kidney disease
Hypertension
• An increasing problem in the US
• 33% of adults have it
• Up to 30% of adults have “white coat
hypertension” not the same as
constant high blood pressure
• Blood pressure is a measure of the
force the blood exerts against the
walls of the artery
• highest at the moment of the heart
beat known as systolic pressure
Hypertension
• Pressure is lower when your heart is at
rest between beats called diastolic
pressure
• The measurements are systolic/diastolic
millimeters of mercury
• 120/80 mm HG is considered normal
• Blood pressure rises as you age
• High blood pressure is known as the silent
killer because it has no physiological
symptoms
Hypertension
• Hypertension can damage the arteries
leading to the brain, kidneys and legs
• Common in African American
• Can be controlled through proper diet and
exercise.
• DASH Diet (Dietary Approach to Stop
Hypertension)
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High in fruits and vegetables
Low in fat, saturated fat, cholesterol and sweets
High in whole grains
Very similar to the recommended diet of MYPyramid
Sodium
• Deficiency symptoms
– rare
• Toxicity symptoms
– Edema, acute hypertension
• Significant source
– Table salt, soy sauce
– Moderate amounts in meats, milks,
breads, and vegetables
– Large amounts in processed foods
Sodium
Shake the Salt habit
• Dilute can foods with water or rinse them
in water to reduce the sodium
• Buy low sodium foods
• Use frozen vegetables instead of canned
vegetables
• Limit portions of deli meats
• Skip the salty fries
Potassium
Roles in the body
• Needed for fluid balance
• Act as a blood buffer
• 95% of potassium in the body is inside the
cells
• Keep the blood pH and acid base balance
correct
• Needed for muscle contraction and nerve
impulse conduction
– A dramatic increase in potassium can lead to
irregular heartbeat or heart attack
– Low levels can cause paralysis
– Potassium is tightly controlled with the help of
the kidneys
Potassium
• Potassium can lower blood pressure
– Causes kidneys to excrete excess sodium
– The dash diet is abundant in foods with
potassium
• Assists in bone health by preventing
calcium and phosphorus from being lost
from bones and kidneys
• Reduces kidney stones by causing the
body to excrete citrate
• Recommendation – 4700 mg/day
• Most adult do not meet their needs daily
Potassium
• Deficiency - hypokalemia
– May occur with dehydration – vomiting or diarrhea
– Use of diuretics or laxative
– Seen in individual who suffer from anorexia and/
or bulimia
• Toxicity - hyperkalemia
– May occur with supplement as a salt substitute
– Irregular heartbeat, damage the heart or result in
death
• Significant sources
– All whole foods
– Meats, milks, fruits, vegetables, grains, legumes
Calcium
Calcium is the most abundant mineral
in the body
• 99% in bones and teeth, 1% in body fluid
• Calcium makes up almost 40% of the
weight of the bones
Functions of Calcium
• Helps to build strong bones and teeth
• Helps to lower high blood pressure
• May help to fight colon cancer by protecting
the lining of the colon
Calcium
Recommended intake
– 1000 to 1200 mg/day
– Upper level 2500 mg/day
sources
–Milk and milk products
–Small fish (with bones)
–Tofu (bean curd), greens (broccoli,
chard), legumes
Calcium
• Deficiency – hypocalcemia
– Stunted growth in children
– Bone loss (osteoporosis) in adults
• Toxicity from supplementation hypercalcemia
– Constipation
– Interfere with absorption of other minerals
• The body can only absorb a maximum
of 500mg of calcium at one time
Osteoporosis
• Weakening and softening of the bone
• Decreased in bone mass
• As older adults begin to hunch over,
they can lose as much as 1 foot in
height
• During adolescence more bone is
added than removed
• Most people reach peak bone mass by
age 30
• After peak bone mass, loss of bone
begin to exceed new bone mass added
Osteoporosis
Factors affecting Osteoporosis
• Inadequate calcium intake
• Gender and hormones
• Genetics and ethnicity
• Physical activity and body weight
• Smoking and alcohol
Phosphorus
The second most abundant mineral in
the body
About 85% in the bone bound with
calcium
Chief functions in the body
– Mineralization of bones and teeth
– Important in genetic material, part of
phospholipids
Phosphorus
• Deficiency - hypophosphotemia
– Blood level becomes low resulting in muscular weakness,
bone pain, rickets and may lead to death
• Toxicity - hyperphosphotemia
– Calcification of non-skeletal tissues, particularly the
kidneys
– Loss of calcium from bone leading to decrease in bone
mass
• RDA
– 1250 mg/day (9-18 yr)
– 700 mg/day (>18 yr)
– Upper level 3000 mg to 4000 mg/day
• Sources
– All animal tissues (meat, fish, poultry, eggs, milk)
Magnesium
• Chief functions in the body
– Helps over 300 enzymes produce inside the
cells
– Needed for metabolism of the macronutrients
– Maintain healthy bones and a regular heart
beat
– Immune system
• RDA
– Men (19-30 years): 420 mg/day
– Women (19-30 years): 310 mg/day
• Upper level for adults: 350 mg nonfood
magnesium/day
Magnesium
• Deficiency
– Hallucinations
– difficulty in swallowing
– In children, growth failure
• Toxicity
– There is no known risk associated with
consumption from food
– Large amounts from supplement can cause
GI problems like diarrhea, cramps, and
nausea
– Some laxatives contain magnesium because
of the cathartic effect
Magnesium
• Significant sources
– Nuts, legumes
– Whole grains
– Dark green vegetables
– Seafood
– Chocolate, cocoa
Chapter 13
The Trace Minerals
The Trace Minerals
• Essential nutrients found in the
human body in <5g.
• Needed in <20mg daily
• Food sources varies widely
• Nutrient interactions is very
common
Iron
• The most abundant mineral on earth
• The most abundant trace mineral in the
body
• An 130 pound woman has about 2300mg of
iron in her body about the size of a dime
• A 165 pound male will have about 4000mg
of iron in his body
• Key component of blood, highly valuable to
the body
• Once absorbed, very little leaves the body
• ~95% of iron in the body is recycled and
reused
• Most iron is lost due to bleeding
Iron
• Occurs in two forms:
– Heme
– found in animal foods
– Part of hemoglobin in red blood cells and
myoglobin in the muscle cells
– Easily absorbed by the body
• Non-heme –
– found mostly in plants foods
– Not easily absorbed as heme iron
In general, the body absorbs only 10 –
15% of the iron ingested
Iron
• You can enhance absorption of iron
by eating a food that’s high in vit C
along with iron rich foods
• As little as 25mg of vit C can double
the absorption of iron
• Eating non-heme iron with heme iron
can also enhance absorption
• Too little or too much iron can be
harmful
Iron
Functions
• Hemoglobin and myoglobin transport
Oxygen in red blood cells
• Hemoglobin picks up carbon dioxide waste
to the lung to be exhaled from the body
• Needed for brain function, involved in the
synthesis of neurotransmitter in the brain
• Cofactor to enzymes
• Involve in making of amino acids,
collagens, and hormones
Iron
Factors that prevent non-heme iron
absorption;
• Phytates and Fibers (found in grains
and vegetables
• Oxalates ( spinach, beets, rhubarb)
• Calcium and phosphorus (milk)
• Food additives
• Tannic acid (found in tea and coffee)
Iron
Deficiency – Iron deficiency is the most
common form of nutritional disorder in the
world
• Symptoms of iron deficiency anemia:
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Decrease in hemoglobin levels
Diminish delivery of oxygen through the body
weakness, fatigue, headaches
Weak immune system
Pica - craving for non nutrient substances like
chalk or ice, common among pregnant women
• Pre-menopausal women, pregnant women,
preterm and low birth weight children and
toddlers are all at risk
Iron
Toxicity from supplementation can
cause:
• Constipation, nausea, vomiting, diarrhea
• In the U.S. accidental consumption of
supplements containing iron is leading cause of
poisoning deaths in children under age 6
• Ingestion of as little as 220mg as been shown to
be fatal
• The FDA requires warning label on iron
supplements that contain 30mg of iron or more
• Iron overload (hemochromatosis)– excessive
storing of iron over several years
Iron
• Food sources
– About half of Americans get their iron
from enriched bread and other grains
– Red meats, fish, poultry, shellfish, eggs
contributes about 12%
– Cooking food in iron skillet can increase
non-heme iron content
Iron
• RDA
– Men: 8 mg/day
• Adult male consume over 16mg on average
– Women (19-50 years): 18 mg/day to cover
loss during menstruation
• Consume about 70% (13mg) of recommended intake
on average
– Women (51+ years): 8 mg/day
– Pregnant women: 27 mg/day
– Vegetarians require 1.8 time higher than non
vegetarians due to components in plant foods
that reduce absorption of iron
• Upper level for adults: 45 mg/day
Zinc
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Zinc is found in every cell of the body
It is involved in more than 100 enzymes
Not considered essential until 1974
Roles
– Needed for DNA synthesis, and for growth and
development
– Helps keep immune system healthy
– Helps in wound healing by reducing
inflammation that usually accompanies wounds
– Helps fight age-related macular degeneration
(AMD) by working with enzymes needed to
produce active vitamin A in the eyes
Zinc
• Rate of absorption varies from 15 to
40%
• During digestion zinc is released in the
pancreas and travel to the small
intestine with dietary zinc
• Zinc is excreted primarily in feces
• Zinc is transported by albumin into the
bloodstream
• Large dose of zinc prevent iron
absorption due to iron binding to
transferrin (protein that carries iron)
Zinc
• Deficiency symptoms
– Hair loss
– Loss of appetite
– Impaired taste of foods
– Delayed sexual maturation
– impotence
• Significant sources
– Protein-containing foods
– Red meats, shellfish
– Whole grains
Zinc
• RDA
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Men: 11 mg/day
Women: 8 mg/day
Upper level for adults: 40 mg/day
Vegetarians can have as much as 50% higher
need for zinc
• Toxicity symptoms
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Stomach pains
Nausea, vomiting, diarrhea
Can lower copper level in the body
More than 300mg can suppress the immune
system and lower HDL (good cholesterol)
Iodine
• Iodine is an essential mineral for the
thyroid glands
• The thyroid need iodine to make
certain hormones that regulate the
majority of the body’s cells
– Regulate body temperature,
– reproduction,
– growth,
– Influence the amount of energy
released during basal metabolism
Iodine
Deficiency
• Hypothyroidism – under activity
of the thyroid hormone
• Goiter – early sign of thyroid
deficiency
• Mental and physical retardation
in babies born to mothers with
iodine deficiency during
pregnancy (cretinism)
Fig. 13-9, p. 456
Iodine
• Toxicity
– overactive thyroid gland
– Reduce the synthesis and release of thyroid
hormones
• RDA for adults: 150 g/day
• Upper level: 1100 g/day
• Significant sources
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Iodized salt,
seafood, bread,
dairy products,
plants grown in iodine-rich soil and animals fed
those plants
Fluoride
Fluoride is the safe form of fluorine, a
poisonous gas
Functions
• Protect against tooth decay
• Helps repair the enamel of the tooth that
has already started to erode
• Interferes with the ability of the bacteria to
metabolize in carbohydrate, reducing the
amount of acid
Fluoride
• AI
– Men: 3.8 mg/day
– Women: 3.1 mg/day
• Upper level for adults: 10 mg/day
• Significant sources
– Drinking water (if fluoride containing
or fluoridated)
– Tea, seafood
Fluoride
• Deficiency symptoms
– tooth decay, especially with children
• Toxicity symptoms
– Fluorosis (pitting and discoloration of
teeth)
– Occurs when teeth are forming, only
infants and children up to age 8 are
at risk
– May occur from swallowing
toothpaste or excessive use of dental
products