Micronutrients

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Micronutrients
Vitamins and Minerals
Micronutrients
• Micronutrients are different from the
macronutrients (Carbohydrates, Protein and
Fat), because they are only needed in very tiny
amounts.
• Nevertheless, they are essential for good
health and deficiencies can cause serious
health problems.
Journal
• As a child, you may have taken a multi vitamin
based on advice from your doctor. At your age
now, do you think it is important to take a
vitamin? Explain.
Vitamins
• Vitamins help keep your body’s tissues healthy
and its many systems working properly. They
also help carbohydrates, fats, and proteins do
their work.
• Some vitamins have antioxidants. These are
substances that protect body cells and the
immune system from harmful chemicals in the
air, certain foods, and tobacco smoke.
Types of Vitamins
• Scientists have
identified 13
different vitamins.
• Only one known
vitamin is
manufactured by the
body- Vitamin D.
Types of Vitamins
• Vitamins are classified into two groups
– Water –soluble: Vitamins that dissolve in water
and pass easily into the bloodstream in the
process of digestion. Water soluble vitamins
include vitamin C and the B vitamins.
– Fat-soluble: Vitamins that are absorbed and
transported by fat. They include vitamins A, D, E,
and K.
Water Soluble Vitamins
Fat Soluble Vitamins-A
Vitamins/Functions
Food Source
Vitamin A
• Helps protect you from
infections
• Helps form and
maintain healthy skin,
hair, mucous
membranes, bones
and teeth.
• Helps you see normally
at night.
• Works as an
antioxidant
•
•
•
•
Dairy Products
Liver
Egg Yolks
Foods high in beta
carotene such as
yellow and orange
fruits and vegetables
and dark green
vegetables
Fat Soluble Vitamins-A
Vitamins/Functions
Food Source
Vitamin A
• Helps protect you from
infections
• Helps form and
maintain healthy skin,
hair, mucous
membranes, bones
and teeth.
• Helps you see normally
at night.
• Works as an
antioxidant
•
•
•
•
Dairy Products
Liver
Egg Yolks
Foods high in beta
carotene such as
yellow and orange
fruits and vegetables
and dark green
vegetables
Fat Soluble Vitamins-D
Vitamins/Functi
ons
Food Source
Vitamin D
• Helps your
body use
calcium and
phosphorus.
• Helps your
body build
strong and
healthy bones
and teeth.
• Fortified Dairy
Products
• Egg Yolks
• High-fat dishsalmon and
mackerel
• Fortified
Breakfast
Cereals and
Margarine
Fat Soluble Vitamins-E
Vitamins/Functio Food Source
ns
Vitamin E
• Works as an
antioxidant.
• Nuts and
Seeds
• Green Leafy
Vegetables
• Wheat Germ
• Vegetable Oils
Fat Soluble Vitamins-K
Vitamins/Function Food Source
s
Vitamin K
• Necessary for
blood to clot
normally.
• Green Leafy
Vegetables
• Fruits and Other
Vegetables
• Dairy Products
• Eggs Yolks
• Wheat Bran and
Wheat Germ
Fat Soluble Vitamins
• If you eat more fat soluble vitamins than your
body needs, they will be stored in the body’s
fat and liver. Your body can then use these
when needed.
• In contrast, water soluble vitamins can not be
stored. They only remain in your body for a
short time. Therefor, you need to get them
every day.
SAFETY WARNING
• Since fat soluble vitamins are stored in the
body’s tissue, an excess buildup of them is
possible, leading to toxic or other damaging
effects.
• An overdose of Vitamin A, for example, can
cause nerve and liver damage, bone and joint
pain, vomiting, and abnormal bone growth.
• People who take vitamin supplements are
advised to use caution.
Check…
• Pick any vitamin and write down whether it is
water or fat soluble, the function in the body,
and food sources that supply this vitamin.
JOURNAL
Yesterday we learned all about vitamins. Think of what you ate
for breakfast this morning. What vitamins did you get? You may
need to look back in your notes. If you did not eat breakfast,
think back to dinner last night!
Minerals
• Like vitamins, minerals are vital for good health.
• Minerals can be divided into three groups:
– Major Minerals: Needs in relatively large amounts.
These include calcium, phosphorus, and magnesium.
– Electrolytes: Specific major minerals that work
together to maintain the body’s fluid balance. These
include potassium, sodium, and chloride.
– Trace Minerals: Needed in very small amounts but
are just as important. They include zinc, iron,
copper, iodine, and selenium.
Meeting Your Mineral Needs
• While the need for some minerals is small,
getting the right amount is important to your
health.
• For example, getting too much or too little
iodine can cause thyroid problems. The
thyroid gland, located in the neck, produces
substances needed for growth and
development.
• For certain people, getting too much sodium,
or too little potassium, may be linked to high
blood pressure.
Meeting Your Mineral Needs
• Getting the right balance of minerals is not
difficult.
• The key is to eat a wide variety of foods.
• However, it is important to pay special
attention to whether you are getting enough
calcium and iron. –two major minerals
especially important for teens!
Major (M) and Trace (T) Minerals
M
M
M
M
T
T
T
T
Calcium and Strong Bones
• One important function is to maintain bone
strength.
• Lack of calcium can lead to OSTEOPOROSIS.
– A condition in which weak bones become
porous, making them weak and fragile. As a
result, posture may become stooped and
bones can break easily.
Calcium and Strong Bones
• Osteoporosis affects over
25 million Americans, both
men and women, though
most common in women.
• It is estimated that up to 50
percent of women over age
45 and 90 percent of
women over age 75 have
osteoporosis.
Calcium and Strong Bones
• You can lessen your risk of osteoporosis, BUT
YOU NEED TO START NOW!
• Bone mass builds up during childhood, the
teen years, and young adulthood.
• The more you do to build healthy bones now,
the less likely you will be to develop
osteoporosis when you are older.
Bone Building Tips
• Eat plenty of calcium-rich foods. These
include dairy products, dry beans and peas,
and dark green leafy vegetables.
• Follow other basic guidelines for healthy
eating. Nutrients work in teams. For
example, Vitamin D and other nutrients work
together with calcium.
• Exercise regularly to help build and maintain
strong bones.
• Avoid tobacco, alcohol, and caffeine. All of
these may contribute to osteoporosis.
How Much Calcium is in Your Bones
• Lets Find Out!
How Much Calcium
Are You Getting?
Iron and Red Blood Cells
• Iron is necessary for making hemoglobin, a
substance in your red blood cells that carries
oxygen to all the other cells in your body.
• If you do not get enough iron, your blood may
not be able to carry enough oxygen to your cells.
• The resulting condition is call iron-deficiency
anemia.
• People with anemia are often tired, weak, short
of breath, and pale.
Where Can You Find Iron?
• Some sources are lean red meat, dry beans
and peas, dried fruits, grain products, and
dark green, leafy vegetables.
• Eating food rich in vitamin C at the same time
as foods rich in iron helps the body absorb
more of the iron from plant foods.
Phytochemicals
• A disease fighting nutrient found in plant
foods.
• Every plant has at least 50-100 different types.
• One of the best know phytochemicals is betacarotene, a substance that gives fruits and
vegetables their bright yellow-orange and
dark green colors. It is an antioxidant believed
to prevent certain kinds of cancer.
Review Questions
• Why do you need calcium? Iron? What foods
provide these nutrients?
• Why are trace minerals just as important as
other minerals, even though they are needed
in such small amounts?
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