Transcript Vitamins

Vitamins
What are vitamins
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Organic molecules needed
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for some enzymes to function properly
To act as antioxidants, getting rid of free radicals
that can cause DNA mutations
Inorganic molecules, by the way, are
minerals
History
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1795, British Navy ships carried a mandatory
supply of limes or lime juice to prevent scurvy
among the sailors – they were given the
name “limeys”
Japanese Navy gave sailors whole grain
barley to ward off beriberi
It wasn’t til 1912 that people knew why these
“prescriptions” worked to prevent diseases
Vital-amine
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Casimir Funk named vitamins – vital amines
because they were compounds that
contained nitrogen (amines contain nitrogen)
and were vital for health
Along with Frederick Hopkins, they came up
with the idea that scurvy and beriberi were
diseases that resulted from the deficiency of
certain compounds that could be found in
foods.
Important Vitamins
There are 18 vitamins and minerals essential in
a healthy diet…but IB only wants you to
know detailed info about:
 Vitamin A (retinol)
 Vitamin C (Ascorbic Acid)
 Vitamin D (Calciferol)
Vitamin Classification
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Fat-soluble vs Water soluble
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Too much of a water soluble vitamin = ok, comes
out in urine
Too much of a fat soluble vitamin = sickness
because it doesn’t dissolve in your urine readily
and gets stored in your body.
Fat soluble vitamins:
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All Dogs Eat Kibbles
CH3
CH3
CH3
OH
Vitamin A
CH3
CH3
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Required for the production of rhodopsin (light-sentistive
material in the rods of the retina).
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Too Little:
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Nightblindness
Xeropthalmia –have difficulty producing tears
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Effects about 500,000 children in underdeveloped nations
Dry mucous membranes
Too Much:
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Makes you think you have a brain tumor
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Headache, vomiting, nausea, abnormal vision, loss of hair
Some precursers can make you turn orange =)
Vitamin A Poisoning
A bizarre case of extreme vitamin A
poisoning was reported by Artic explorers
who killed and ate a polar bear. Those who
ate the liver became very ill and three of
them lost patches of skin. Later,
scientists discovered that 0.25 lb of the
liver contains 2.5 yrs worth of Vitamin A
for humans.
How do we get vitamin A?
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2 Chemicals: Retinoids and carotenoids
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Retinoids – body can use right away
Carotenoids – body can change it into a retinoid
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Beta-carotene (Why are carrots good for your eyes? Have you
ever seen a rabbit with glasses?)
Carotenoids don’t get stored in liver
Foods with 25% of your RDA for Vitamin A
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Cearal 1oz, oatmeal 2.3 cups
Fruit: apricots, canteloupe, mango (1/2 c)
Veggies: carrots, kale, peas, sweet peppers (1/2 c cooked)
Meat: Liver 3oz
Milk: 2 cups
OH
HO
OH
Vitamin C
HO
O
O
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Required for
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Too Little:
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Production of collagen: the protein of connective tissue.
Antioxidant
Protects immune system, helps fight off infection, reduces allergic
reactions
Scurvy (bleeding gums; tooth loss; mosebleeds; bruising; painful
or swollen joints; shortness of breath, increased susceptibility to
infection, skin rashes; muscle pains, slow wound healing)
Too Much:
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More than 1000 mcg may cause upset stomach, diarrhea, or
constipation
How do we get Vitamin C?
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On the label, look for:
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Sodium ascorbate
Isoacrobate
Ascorbic acid
Foods with 25% of RDA
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Did you know that many foods are
preserved with sodium nitrite to
prevent the growth of bacteria. At
high T, nitrite + protein forms
carcinogen. Vitamin C prevents that
rxn so it is added to processed
meat, too.
Cereal: 1 oz
Meat: Liver 3oz
Fruit: Canteloupe, grapefruit, mango, orange, strawberries,
½ c.
Veggies: Asparagus, broccoli, brussel sprouts, kale,
kohlrabi, sweet peppers, snow peas (cooked) ½ c. sweet
potato: 1 med.
CH2
CH3
Vitamin D
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Required for the uptake of calcium and phosphorus
from food.
H3C
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Too little:
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CH3
can cause weak bones (Rickets) in children
In adults: osteomalacia (soft bones, fracture easily)
Too much:
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Kidney stones and hard lumps of calcium in muscles and
organs
Headache, nausea, vomiting, high blood pressure, retarded
physical growth and mental retardation in children, fetal
abnormalities
CH3
How do we get Vitamin D?
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3 forms
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Calciferol: occurs in fish oils, egg yolks
Cholecaliferol: created when sunlight hits skin, reacting with
steroids in body fat just underneath skin
Ergocalciferol: found in plants
Some people claim that you
Foods with 25% of RDA
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Salmon or tuna 1.5-2 oz
Eggs: 3
Milk: 1 cup
should not use sunscreen so
that your body can use the
sunlight to produce Vitamin D.
Most doctors, though, advise
getting Vitamin D through
your food and wear a high SPF
sunscreen at all times.
Fortified Foods
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Foods are fortified to provide us with the
nutrients we need to stay healthy
Ex: milk is fortified with vitamin D
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A pre-curser to vitamin D is extracted from plants,
then irradiated to make an active form of Vitamin
D, then it is added to food
Cooking and vitamin absorption
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Studies show that cooking foods can cause a
decrease in the amount of vitamins in the
food
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Water soluble vitamins dissolve in cooking water
Some vitamins are broken down by heating
Some vitamins, though, are better than no
vitamins. So eat your veggies, cooked or
not.