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Vitamins minerals and water

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Section 8.2 Vitamins, Minerals, and Water
Vitamins, Minerals, and Water
Objectives
Identify the two main classes of vitamins.
List seven minerals your body needs in
significant amounts.
Explain why water is so important to your body.

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Section 8.2 Vitamins, Minerals, and Water

Myth As part of a healthy diet, people need to take
dietary supplements
Fact A diet that contains a variety of healthful foods
usually supplies all the vitamins and minerals that your
body needs

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Section 8.2 Vitamins, Minerals, and Water

Vitamins
• One of the first discoveries of the
importance of vitamins came in the
1700s.
• A Scottish doctor, James Lind,
discovered that sailors who were fed
citrus fruits recovered from scurvy.


• Today, health scientists know that scurvy
is caused by a lack of vitamin C, which is
found in abundance in citrus fruits.

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Section 8.2 Vitamins, Minerals, and Water

What Are Vitamins?
• Nutrients that are made by living things, are required
only in small amounts, and that assist many
chemical reactions in the body are vitamins.
• A nutrient that helps the body use carbohydrates,
proteins, and fats is a vitamin.
• There are two classes of vitamins
• fat-soluble vitamins—dissolve in fatty material
• water-soluble vitamins—dissolve in water

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Section 8.2 Vitamins, Minerals, and Water

Fat-Soluble Vitamins
• Fat-soluble vitamins can be stored by the body
• Vitamins A, D, E, and K are fat-soluble vitamins
• Sources of fat-soluble vitamins are
• vegetable oils
• liver

• eggs
• certain vegetables

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Section 8.2 Vitamins, Minerals, and Water

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Section 8.2 Vitamins, Minerals, and Water

Water-Soluble Vitamins
• Water-soluble vitamins cannot be stored by the
body.
• Examples of water-soluble vitamins are C and all of
the B vitamins.
• Sources of water-soluble vitamins are
• fruits
• vegetables
• whole-grain foods
• and many other foods

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Section 8.2 Vitamins, Minerals, and Water

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Section 8.2 Vitamins, Minerals, and Water

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Section 8.2 Vitamins, Minerals, and Water

Antioxidants
• Vitamins called antioxidants help protect healthy
cells from the damage caused by the normal aging
process as well as from certain types of cancer.
• Vitamins C and E are two of the most powerful
antioxidants.
• Vitamin C helps strengthen blood vessel walls,
strengthens your immune system, and aids in iron
absorption.

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Section 8.2 Vitamins, Minerals, and Water

Minerals
• A nutrient that regulates many chemical reactions in the
body is a mineral.
• Occurs naturally in rocks and soil
• Minerals that are required in amounts greater than
100mg are considered macro minerals.

• Calcium, sodium, potassium, magnesium,
phosphorus, chloride (chlorine), and sulfur
• Your body requires very small amounts of trace minerals.
• Iron and zinc

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Section 8.2 Vitamins, Minerals, and Water

Calcium
• Calcium is important in blood clotting and the
functioning of your nervous system.
• It is an essential ingredient in the formation and
maintenance of bones and teeth.
• A lack of calcium can sometimes lead to
osteoporosis, a condition in which the bones
gradually weaken.

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Section 8.2 Vitamins, Minerals, and Water

Potassium
• Potassium and sodium work together to maintain
water balance in the body.
• Most Americans do not consume enough potassium.

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Section 8.2 Vitamins, Minerals, and Water

Iron
• Iron is necessary for healthy red blood cells.
• If a person’s diet does not include enough iron, he or
she may develop anemia, a condition in which the
red blood cells do not contain enough hemoglobin.

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Section 8.2 Vitamins, Minerals, and Water

Sodium
• Sodium is important in several body processes,
including the functioning of the heart and water
balance.
• Too much sodium can cause a problem with blood
pressure.

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Section 8.2 Vitamins, Minerals, and Water

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Section 8.2 Vitamins, Minerals, and Water

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Section 8.2 Vitamins, Minerals, and Water

Vitamin and Mineral Supplements
• Vitamin and mineral supplements, therefore, are not
usually necessary if your diet is nutritious and wellbalanced.
• An excess, or overdose, of vitamins or minerals may
damage your health.
• If you do take a vitamin or mineral supplement, a
health care provider can advise you about how much
is the right amount.

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Section 8.2 Vitamins, Minerals, and Water

Water
• About 65 percent of
your body weight is
water.
• Nearly all of the
body’s chemical
reactions, including
those that produce
energy and build new

tissues, take place in
a water solution.

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Section 8.2 Vitamins, Minerals, and Water

Water and Homeostasis
• Homeostasis is the process of maintaining a steady
state inside your body.
• When you become overheated, your body excretes
perspiration, which cools your body. Thus, water
regulates body temperature.
• Water contains dissolved substances called
electrolytes that regulate many processes in your
cells.

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Section 8.2 Vitamins, Minerals, and Water

Preventing Dehydration
• Dehydration is a condition in which the water
content of the body has fallen to an extremely low
level.
• Symptoms of dehydration can include fatigue, dry
mouth, dizziness, weakness, flushed skin, headache,
blurred vision, difficulty swallowing, dry skin, rapid

pulse, and a infrequent urination.

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Section 8.2 Vitamins, Minerals, and Water

Dehydration and Blood Viscosity
• Blood plasma is about 90% water.
• As the body loses water during dehydration, the
blood thickens, making it harder for the heart to pump
blood through the body.

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Section 8.2 Vitamins, Minerals, and Water

How Much Water?
• Every day, you need at least ten 8-ounce cups of
water if you are a female 14 to 18 years old.
• Males in the same age group need 14 cups of water
per day.

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Section 8.2 Vitamins, Minerals, and Water

Water Versus Sports Drinks

• A sports drink is not necessary if you exercise for 60
minutes or less.
• If you exercise longer, a sports drink that contains
carbohydrates may be beneficial.
• Sports drinks with electrolytes are not necessary
unless you exercise for 5 hours or more.

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Section 8.2 Vitamins, Minerals, and Water

Herbal Supplements
• Supplements that contain extracts or ingredients from
the roots, berries, seeds, stems, leaves, buds, or
flowers of plants are herbal supplements.
• Herbal supplements are officially classified as food
and not drugs.
• This means that herbal or dietary supplements do
not have to be proven safe or screened by the
FDA before placed on the market

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