Vitamins

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Macronutrients and
Micronutrients:
Vitamins and Minerals
L. Scheffler
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Micronutrients
and Macronutrients


Micronutrients are substances required in very small
amounts (mg or μg) and that mainly function as
co-factors of enzymes ( < 0.005% body weight).
Examples include:
1. Vitamins
2. Trace minerals (Fe, Cu, F, Zn, I, Se, Mn, Mo, Cr,
Co and B).
Macronutrients are chemical substances that are
required in relatively large amounts (> 0.005% body
weight).
Examples include proteins, fats, carbohydrates and
minerals (Na, Mg, K, Ca, P, S, and Cl).
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Micronutrients
Vitamins and Minerals
Vitamins and minerals are essential for the
maintenance of good health and the
prevention of a number of diseases.
• Vitamins are generally organic molecules
• Minerals are inorganic substances usually in ion
form
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Micronutrients
Vitamins

Vitamins are naturally occurring organic
compounds that are essential to metabolic
or other functions in the body.

Most vitamins cannot be synthesized by
the body. They must be supplied in the
diet.
Vitamins are usually classified as water
soluble or fat soluble

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Micronutrients
Minerals



Minerals are inorganic and are found in the
soil and water absorbed by plants or eaten by
animals.
The human body requires substantial amounts
of minerals on a daily basis to ensure proper
functioning of the organs, bones, tissue and
immune system.
Minerals may be classified as macro-minerals
or trace minerals
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Minerals

Macro-minerals

Trace Minerals
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Minerals

Trace Minerals

Macro-minerals
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Minerals
Mineral
What the mineral does
Food sources
Sodium
Fluid and electrolyte balance, supports
muscle contraction and nerve impulse
transmissions
salt, soy sauce, bread, milk, meats
Chloride
Maintains fluid and electrolyte balance,
aids in digestion
salt, soy sauce, milk, eggs, meats
Potassium
Maintains fluid and electrolyte balance,
cell integrity, muscle contractions and
nerve impulse transmission
potatoes, vegetables, banana,
strawberries, cod, milk
Calcium
Formation of bones and teeth, supports
blood clotting
milk, yogurt, cheddar cheese,
Swiss cheese, tofu, sardines,
green beans, spinach, broccoli
Phosphorus Formation of cells, bones and teeth,
all animal foods (meats, fish,
poultry, eggs, milk)
Magnesium Supports bone mineralization, protein
Green vegetables, tomato juice,
beans, cashews, halibut
maintains acid-base balance
building, muscular contraction, nerve
impulse transmission, immunity
Iron
Part of the protein hemoglobin (carries
oxygen throughout body's cells)
spinach, broccoli, green beans,
tomato juice, beef liver
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Minerals
Mineral
Function
Food sources
Zinc
Enzymes production of genetic
material/proteins, vitamin A transport,
wound healing, sperm production and the
normal development of the fetus
Green vegetables, tomato juice
,lentils, oysters, shrimp, crab,
meats yoghurt, cheese
Selenium
Antioxidant, works with vitamin E to
protect body from oxidation
seafood, meats and grains
Iodine
Thyroid hormones regulate growth,
development and metabolic rate
salt, seafood, bread, milk,
cheese
Copper
Absorption/utilization of iron, formation of
hemoglobin , enzymes
meats, water
Manganese
Facilitates many cell processes
widespread in foods
Fluoride
formation of bones and teeth, helps to
make teeth resistant to decay
fluoridated drinking water, tea,
seafood
Chromium
Associated with insulin and is required for vegetable oils, liver, whole
the release of energy from glucose
grains, cheese, nuts
Molybdenum Facilitates many cell processes
legumes, organ meats
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Vitamin Characteristics





Each vitamin has one or more specific
purposes.
Vitamins are essential to life processes.
Vitamins are generally used by the body
with very minimal changes
Vitamins are usually required in only small
amounts
Most vitamins cannot be synthesized by
the body directly
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Important Vitamins
Vitamin
Function
Source
Supports vision, skin, bone and
tooth growth, immunity and
reproduction
mango, broccoli, butternut
squash, carrots, tomato
juice, sweet potatoes,
pumpkin, beef liver
Collagen synthesis, amino acid
metabolism, helps iron
absorption, antioxidant
Fruits and vegetables
D
Promotes bone mineralization
Self-synthesis milk, egg
yolk, liver, fatty fish
B12
New cell synthesis, Breaking
down fatty acids / amino acids,
nerve cell maintenance
Meats, poultry, fish,
shellfish, milk, eggs
E
Antioxidant, regulation of
oxidation reactions, supports cell
membrane stabilization
Shrimp, cod, wheat
germ, tofu,
polyunsaturated
vegetable oils, sweet
potatoes,
K
Synthesis of blood-clotting
proteins, regulates blood calcium
Liver, leafy green vegetables,
spinach, broccoli, cabbage, 11
A
Retinol
C
Ascorbic Acid
Classification of Vitamins
Vitamins can be classified as either
• Water soluble
• Fat soluble.
 Water soluble vitamins are generally
involved in the cellular metabolism
of energy supplying nutrients.
 Fat soluble vitamins often have very
specialized functions

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Water Soluble Vitamins



Water soluble vitamins usually contain
hydrogen attached to electronegative
atoms such as oxygen or nitrogen.
They easily form hydrogen bonds with
water molecules.
Water soluble vitamins do not accumulate
in the body, so regular supplies are
necessary
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Water Soluble Vitamins

Examples of water soluble vitamins
Vitamin C
Vitamin B1 (Thiamine)
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Fat Soluble Vitamins


Fat soluble vitamins have long nonpolar
hydrocarbon chains or rings.
Common fat soluble vitamins include
• A,
• D,
• E,
•F
• K.
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Fat Soluble Vitamins


Fat soluble vitamins usually accumulate in
tissues and are not leached out quickly.
Unlike water soluble vitamins, an excess
of a fat soluble vitamin can be just as
harmful as a deficiency
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
Examples of Fat Soluble
Vitamins
Vitamin D
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Examples of Fat Soluble
Vitamins
Vitamin K
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Vitamin C- Sources




Vitamin C is found in many
fresh fruits and vegetables.
It contains several polar
groups, making it very water
soluble.
Cooking vegetables in water
tends to leach the vitamin
from the food.
Cooked foods also contain
less vitamin C, since it is also
easily oxidized and hence
destroyed in the cooking
process.
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Vitamin Functions
Involved in the
biosynthesis of the
protein, collagen, found in
connective tissues such
as cartilage, ligaments,
and tendons
 Aid in healing wounds
and helping to prevent
bacterial infections.


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Vitamin C Functions
Massive doses of vitamin
C have often been
thought to help in the
prevention of the common
cold,
 There is NO reliable
evidence to show that this
is true


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Vitamin C Deficiencies



Scurvy or Scorbutus.
Symptoms include
1. swollen legs,
2. rotting gums,
3. and bloody lesions.
Common among sailors in
the 18th and 19th centuries
who spent a long time at
sea without fresh fruits
and vegetables
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Vitamin A
Vitamin A is also known as retinol
The long chain hydrocarbon structure of vitamin A
means that the vitamin is essentially non-polar.
Hence it is fat soluble rather than water soluble.
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Vitamin A Sources


Commonly found in cod liver oil, green vegetables,
and fruit.
Carrots indirectly serve as a source of vitamin A
since they contain b carotene which the body
readily converts to vitamin A
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Vitamin A Functions



Vitamin A is fat soluble.
It is not readily broken down by cooking.
Role in aiding in night vision.
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Vitamin A Functions


Retinol is oxidized to retinal, which combines
with the protein opsin to form rhodopsin.
Rhodopsin is the active agent which converts
light signals to electrical impulses that the
optic nerve transmits to the brain
Retinol
Retinal
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Vitamin A Deficiencies


A deficiency in vitamin
A results in night
blindness.
The most serious
deficiency results in a
condition known as
Xeropthalmia, a severe
form of conjunctivitius
or blindness.
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Vitamin D - Sources


Vitamin D is commonly found in fish liver oil as
well as egg yokes.
Unlike other vitamins, the body synthesizes
vitamin D in the skin through the action of
ultraviolet light on 7-dehydrochlosterol
Like vitamin A, the long
chain Hydrocarbon
structure makes vitamin D
fat soluble
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Vitamin D Functions



Vitamin D is an important regulator of
calcium metabolism.
It is involved in the uptake of calcium and
phosphate ions from food into the body.
It is necessary for the proper formation of
bone structures and teeth.
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Vitamin D


A serious deficiency in vitamin D results
in a condition known as Ricketts.
Ricketts is characterized by bone
softening an malformation.
Child with Ricketts
and two years after
treatment 
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Vitamin D

Vitamin D is destroyed by bleaching agents that
are often used in the manufacture of purified
white flour
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Micronutrient Deficiencies
Vitamin Deficiency Diseases
• Retinol (Vitamin A) 
xerophthalmia / night blindness
• Ascorbic acid (Vitamin C) 
scurvy or scorbutus
• Calciferol (Vitamin D)  rickets.
• Niacin (Vitamin B3)  pellagra
• Thiamin (Vitamin B1)  beriberi
Mineral Deficiency Diseases
• Iron — anemia
• Iodine — goiter
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Macro-nutrient Deficiencies
Macronutrient deficiencies diseases in chlidren
often result from a lack of protein
Kwashiorkor is a specific
wasting away often
occurring in infants at
weaning. It results from a
lack of protein in the diet
Marasmus is a wasting away of
the body tissues from the lack Kwashiorkor
of calories as well as protein in
the diet. The child is fretful
rather than apathetic and is
skinny rather than swollen with
edema.
Marasmus
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Nutritional Deficiencies
Proposed approaches to combating
nutritional deficiencies world-wide include:
• Providing food rations that are composed
of fresh and vitamin- and mineral-rich
foods.
• Adding nutrients missing in commonly
consumed foods.
• Genetic modification of food.
• Providing nutritional supplements.
• Providing selenium supplements to people
eating foods grown in selenium-poor soil.
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