1.
What is nutrient?
Nutrient is a chemical substance found in
foods and used in the human body. Nutrients gives you energy, strengthen your
bones and muscles and even protect you from getting disease. There are two
different types of nutrients that you must be aware of: essential nutrient and
non-essential nutrient
Essential nutrients are the nutrients that
cannot be synthesized by your body and thus has to be consumed from food
intake. On the other hand, there is a few nutrients that are not essential. Non
essential nutrients can be synthesized in the body from other nutrients or
found from alternative sources. Yet, if they are involved in diet, the need for
biosynthesis of non essential nutrients is diminished.
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Essential
nutrients
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Non-essential
nutrients
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1.
Water
2.
Some of fatty acids
e.g. omega-3 linoleic acid and omega-6
linoleic acid
3.
Some vitamins
e.g. A, some B vitamins, C, D, folate
4.
Dietary minerals
e.g. iron, potassium, sodium, calcium,
phosphorous and iodine
5.
Some amino acids
e.g. phenylalanine and methionine
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6.
Carbohydrates
(but energy can come from other sources such
as lipids and proteins)
7.
Other lipids and fatty acids
8.
Other vitamins
9.
Other minerals
10.
Other amino acids
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Then how are the non-essential nutrients
synthesized in the body? Out of twenty different amino acids, eleven of them
are non essential meaning they can be synthesized in the body from other
nutrients. Yet, the human body will only expend the energy required for their biosynthesis
if they cannot be derived from the diet.
*Biosynthesis:
production of non essential nutrients in the body from components of essential
nutrients
2.
Protein deficiency malnutrition
Protein
deficiency malnutrition is caused by inadequate supply of one or more essential
amino acids and it is the key factor of ‘kwashiorkor’. The disease is most frequently found in
children and infants in Africa and Central America. It is especially common in
developing countries that are experiencing famine, political unrest and natural
disasters. Consequences of Kwashiorkor include stunted growth, muscle and skin
problems, impaired mental problems, immune system impairment, oedema.
(Oedema
is a swell of abdomen and legs as plasma proteins responsible for controlling
the tissue fluid are not projected and thus fluids build up.)
3.
Phenylketonuria(PKU)
Phenylketonuria(PKU) is a genetic mutation
changes of the gene coding for tyrosine hydroxylase which is responsible for
metabolizing phenylalanine in to tyrosine. Phenylalanine is instead converted
into phenyl pyruvic acid; resulting in a high level of ketones in the blood and
urine. Over time, this may result in brain damage or mental retardation.
Diagnosis of phenylketonuria can be made by a
simple blood test for the levels of phenylalanine. As PKU results in the build
up of phenylalanine in the bloodstream, it is treated by following a special
diet that is low in protein.
Diet
should include fruits, grains, vegetables and special formula milk and must be
undertaken from early in life or else symptoms will appear. Symptoms may
include tremors, seizures, eczema, skin rashes and eventually brain damage
(mental retardation)
4.
Fatty acids
Fatty acids all have the same general
structure, but there maybe variation in the bonding between carbon atoms.
Saturated fatty acids have no carbon double bonds while unsaturated fatty acids
do have some double bonds between carbon atoms. The unsaturated fatty acids can
be divided into mono-saturated with single double bond and poly-saturated with
multiple double bonds. There is another variation as well: cis-isomers that
hydrogen attached to the double bonded atoms are on the same side and
trans-isomers that have hydrogen on opposite sides.
All types of fatty acids consumed as part of
dietary intake will cause weight gain and increase risks of hear disease if
taken in excessive amounts. There are several different health effects of
consuming different types of fatty acids explained below.
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Saturated
fatty acids
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Unsaturated
fatty acids
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Cis-fats
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Trans-fats
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Sources
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Animal
fats, butter, milk, cheese
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Vegetable
oils, fish oils
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Hydrogenated
vegetable oils, margarine
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Effects
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1.
Raise harmful LDL cholesterol
2.
Leads to atherosclerosis and coronary heart
disease(CHD)
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3.
Promotes beneficial HDL cholesterol
4.
Inhibits harmful LDL cholesterol
5.
Omega-3 linked to brain development
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6.
Significantly raises LDL cholesterol
7.
Strong links to atherosclerosis and CHD
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Bibliography
