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12.2 Vitamins
chapter 19
MICRONUTRIENTS 2
Vitamins are nutritionally important organic compounds.
Often coenzymes or cofactors for enzyme function.
Vitamins form biochemically through the life processes of the plants and animals we eat.
Plants and animals synthesize vitamins.
Originally it was thought these necessary compounds were all amines. Since they were vital to our health they became known as “vital amines”, ie. vitamines.
When it was discovered that some were not amines, ie. not ' --ines', the name was changed to
vitamins.
The fat - soluble vitamins are much more soluble in fats, hydrocarbons and similar solvents than in water
Vitamins A, D, K, E
Water- soluble vitamins are much more soluble in water than in 'organic' solvents.
C, B complex (B1,2,3,6,12), Pantothenic acid(B5), Biotin(B7), Folate(B9)
Vitamin Requirements
Water-Soluble
Thiamin (B1) Riboflavin (B2) Niacin (B3) Pantothenic acid (B5) Pyridoxine (B6) Biotin (B7) Folic acid (B9) Cobalamin (B12) Ascorbic acid (C)
Name(Letter) RDI
1.5 mg 1.7 mg 2 mg
10 mg 2 mg 0.3 mg 0.4 mg 6
g 60 mg
Vitamin Requirements
Name(Letter) RDI
Retinol (A) Calciferol (D) *Tocopherol (E) Phylloquinone (K)
Oil-soluble
5000 IU
400 IU
30 IU
70 g
WHAT is An IU??
Vitamin levels in foods or supplements are sometimes stated in Retinol Equivalents (RE's) or in International Units (IU's). (2 sets of Units!!)
Several esters of retinol are equally effective and thus are retinol equivalents (RE’s).
By definition , 1 RE of retinol = 1 microgram
Also by definition, one International unit (IU) of Vitamin A =.3 micrograms retinol
Thus 1 RE=3.33 IU’s of Vitamin A
IU’s
• Can apply to all vitamins and always = 0.3 micrograms or 0.3 x10-6 grams
• RE’s only apply to Vitamin A (retinol)
2 Retinols(A) from 1 beta carotene
Metabolism of beta carotene
• Oxidative cleavage of C=C and reduction to alcohol
• Carrots etc. lots of beta carotene and eventually an excellent source of Vitamin A
Free radical = unpaired electron very reactive
Oxygen radicals: Hydroxy (HO•) / Peroxy (HOO•)
OH
OH
OH
OH
.
.
Free Radicals - the Metabolic Oxidizers
Do you smoke??
• Each puff contains ~ 1015 OH radicals
• Also cyanides (bind to hemoglobin)
• PNAH’s
• Try the blow test: exhale through a kleenex and see the tar!
What’s in cigarette smoke?
An antioxidant is a chemical so easilyoxidized itself that it protects others from oxidation.
Double Bondeg. Vitamin A
PhenolPart of Vitamin E molecule
OH
and / or
Repel the Enemy !
Vitamins - Some Generalities• Fat-soluble vitamins can be accumulated in body tissue/organs, eg. liver. Often there can be serious metabolic consequences when ingesting 'mega- doses', ie.10 - 100X the RDI.
• The water-soluble vitamins are often destroyed by heat/water in the cooking process; also by prolonged storage. Since they are excreted there is
usually no danger from 'overdosing' (vit B6!).
• Diet-related deficiencies do occur in vegans, the elderly and alcoholics
• Chirality! ie. natural (D or L) vs. synthetic (D/L)
C H 3 C H 3 C H 3
C H 3
CH 2 OH
C H 3
Retinol (Vitamin A)
HO
CH2
CH3
C H 3 C H 3
C H 3
Cholecalciferol (Vitamin D3)
Fat-Soluble Vitamins ( A & D)
O
C H 3
C H 3 C H 3
O H
C H 3
C H 3
C H 3 C H 3 C H 3
-Tocopherol (Vitamin E)
O
O
C H 3
CH 2
CH
C
CH 3 C H 3
H
3
Phylloquinone (Vitamin K)
Fat-Soluble Vitamins ( E & K)
CH3 CH NH
CH2
CH2
CH2HOH2C
O
OH
COOH
CH3
N
S
N
N
CH3
CH2
CH2
15
NH2
CH3
OH
+
Water-Soluble Vitamins ( B1 & B5)
Thiamine (B1)
Pantothenic Acid (B5)
Water-Soluble Vitamins (B2 & B6)
N
COOH
NH NH
S CH2
CH2
CH2
CH2
COOH
O
OO
OH OH
OH
OH
Water-Soluble Vitamins (B3,B7,C &?)
Niacin(B3)
Biotin(B7)
Ascorbic Acid(C)
HOCH2CH2N+(CH3)3
Choline
Natural = Ascorbic Acid = Synthetic
Water-Soluble Vitamin (B9)
Water-Soluble Vitamin(B12)
Cobalamin
A - Retinol
Uses: vision pigment, good anti-oxidant (heart disease? cancer?)
Deficiency: night blindness, (infant mortality)
Excess: blurred vision, teratogenic for pregnant women, serious liver disease,skin yellowing
Sources: highly coloured vegetables, liver, egg yolks, fish liver oils
D - Calciferol
Uses: regulates absorption of calcium & phosphorus
Deficiency: rickets (bone deformation)
Excess: damage to kidneys/tissue due to Calcium 'deposits'
Sources: eggs, liver, fish oils, fortified milk, sunshine
E - Tocopherol
Uses: excellent anti-oxidant (protects cell membranes); skin care
Deficiency: rare; (anemia, edema in infants)
Excess: 2005 study*** Heart attacks if overused
Source: vegetable oils, green vegetables, nuts/seeds, wheat germ, meat
Vitamin E is not recommended over and above what is in a multivitamin as of 2005
E: the vitamin looking for a disease!
• Still no well documented evidence for any diseases directly due to its deficiency.
• Don’t take supplements!
K- Phylloquinone
Uses: essential cofactor in blood clotting
Deficiency: (bruising/bleeding in infants-increased coagulation time)
Excess: dangerous if taking anti-coagulants such as ASA
Sources: green leafy vegetables (spinach, kale)
Cofactor: a small molecule or atom that is required for an enzyme to be active
B1- Thiamin
Uses: necessary for carbohydrate metabolism
Deficiency: nervous system deterioration (beriberi),
esp. in Far East because of milled rice
Excess: not known
Sources: lean meat, legumes, whole grains, in 'fortified' flour since 1940s
B2 - Riboflavin
Uses: cofactor in much metabolism
Deficiency: poor wound healing, breakdown of tissue in mouth/nose
Excess: not likely (yellow urine!)
Sources: milk, organ meats, fortified cereals
Uses: required for all metabolic oxidations (needed
by every cell daily!), lowers cholesterol (in excess)
Deficiency: deterioration of nervous system & skin (pellagra)
Excess: not normal (dizziness, liver damage)
Sources: yeasts, meats, legumes, 'enriched' flour
B3 - Niacin
B5 - Pantothenic Acid
Uses: cofactor in fatty acid metabolism
Deficiency: not observed
Excess: not observed
Sources: organ meats, egg yolks, yoghurt, legumes
Uses: cofactor in >60 enzymes for a.a. metabolism (the master vitamin!)
Deficiency: anemia, nervous disorders (est. in almost 50% of NA women, esp. those on oral contraceptives)
Excess: disable nervous system (present in body- building diets)
Sources: green leafy vegetables, meats, fruit
B6 - Pyridoxine
B7 - Biotin
Uses: cofactor in synthesis of fatty acids
Deficiency: not observed
Excess: not observed
Sources: liver, egg yolks, nuts, legumes, soy
B9 - Folic Acid
Uses: cofactor for nucleic acid and heme synthesis
Deficiency: some anemias, if during pregnancy the
fetus has high probability of spina bifida
or other birth defects
Excess: possible danger for hormone related cancers
Sources: green leafy vegetables, asparagus, organ
meats
B12 - Cobalamin
Uses: controlling factor for pernicious anemia
Deficiency: normally rare, but with inability to absorb (>50 and vegans)
Excess: not known
Sources: animal protein, organ meats, milk, eggs
Get your Daily ‘B – Complex’ !
Vegans (ovo-lacto vegetarians)
• Need Vitamin B supplements containing the cobalamin complex or take Brewers Yeast
C - Ascorbic Acid
Uses: cofactor for collagen production, enhances iron absorption, excellent anti-oxidant
Deficiency: scurvy
Excess: probably should avoid >1g/day (Linus Pauling advocated up to 3g/day but no proven benefits!)
Sources: citrus fruits, potatoes, cabbage, tomatoes
Vitamin C - will it cure my cold?
> NO, but….30% decrease in upper respiratory tract infections > ~1/3 of all NA ingests Vit.C = tons! > Loses potency when exposed to air (50% less in your OJ after 3 weeks in fridge). > Helps maintain other antioxidants > Smokers need ~twice the RDI/USRDA
By 1750 it was known that weekly rations of citrus fruit would prevent scurvy. This fact allowed Britain to 'rule the waves' and for these sailors to be called "limeys". Not isolated until 1928.
Phytochemicals - non-nutrient compounds, found in plant-derived foods, that have biological activity in the body.
2009 OJ: packaging “phytonutrients!”
Antioxidants (anti-aging/cancer/heart disease?) - catechins (berries, green/black tea), lycopene
(tomatoes,watermelon), bioflavanoids (citrus fruit, grapes), coenzyme Q (nuts,oils).
HO
HO
CH2
Squalene (Cod Liver Oil)
Solar Radiation
7-dehydrocholesterol,
occurs in the skin
Cholecalciferol
(Vitamin D3)
Formation of Vitamin D
Vitamin A from Carotene
Plant Pigments = Potent Antioxidants
Almost 2000 known plant pigments. >800 flavonoids, ~450 carotenoids and ~150 anthocyanins.
Red(lycopene) – tomatoes, pink/red grapefruit, watermelon, guava, red peppers.
Red/Blue/Purple(anthocyanins) – red/blue grapes, blue-/straw-/raspberries, beets, cherries,
egg plant, plums, red cabbage.
Orange(carotene) – squash, pumpkin, yams, carrots,
mango, cantaloupe.
Colour your Nutritional World !
Orange/Yellow(cryptoxanthin) – peach, orange, nectarine, papaya.
Yellow/Green(lutein, zeaxanthin = especially good for health of eyes) – corn, cucumber skins, yellow/green peppers, green beans/peas, spinach, honeydew melon, kiwi, romaine lettuce,
Plant Pigments = Phytochemicals
Red, Yellow or Green – It’s all a GO !
Had your ORAC Foods Today ?
high Oxygen Radical Absorbance Capacity foods – the top 15(for ~100g/3.5oz)
prunes raisins blueberries stawberries raspberries plums oranges red grapes cherries
5770 2830 2400 1540 1220 949 750 739 670
kale spinach sprouts broccoli beets red pepper corn eggplant carrot
1770 1260 980 890 840 710 400 390 210
Too Much Broccoli ! Two women with diseases characterized by
abnormal blood clotting did not improve when they were given Warfarin. When questioned about their diets, one woman reported that she ate at least a pound of broccoli every day, and the other ate broccoli soup and a broccoli salad every day. When broccoli was removed from their diets, warfarin became effective in preventing the abnormal clotting of their blood. Because broccoli is high in vitamin K, these patients had been getting enough dietary vitamin K to compete with the drug, thereby making the drug ineffective.
Vitamin O - the next miracle supplement!
Recipe: Take 8oz water, add a pinch of salt, bubble
in oxygen/(air?) for 15 seconds then sell for $20(US) + shipping/handling.
Or maybe you would like to visit an 'oxygen bar'? Get fined for US$400,000 (for 'fraudulent claims'), change the wording and keep on selling. To-date an
estimated 1 million bottles have been sold!
Check out the ‘Net’ under ‘vitamin O’ eg. ~first 10 entries on ‘Yahoo’ or ‘Google’
Beware the Scam!!
• Exotic berry/fruit extracts will cure all!
• Goji Juice (from the Himalayas!)
The Master Molecules in Goji Juice
CBC “5th Estate” Aug 31/07
• Goji juice expose!
• Cost is 50$ per liter on sale for 34.95$!
• “Dr” Earl Mindel has fake credentials
• MLM approach (Multi-layer marketing)
Constituents of Goji Juice
• Vitamin C
• Lycopene, carotene, anthocyanine
• All good, but available from readily available fruits/vegs at a fraction of the price!
• Buyer beware!!
Other exotic berries
• Now the acai berry!
• Has 10x the antioxidant properties of grapes and 2x those of blueberries
• Used for generations by Brazilian jungle dwellers!
21 Chief health Benefits of Acai
• Boosts energy levels, improves digestion, improves mental clarity, promotes sound sleep, provides all “vital” vitamins, contains important minerals, powerful free radical fighter, has high fibre levels, cleans and detoxifies the body, strengthens immune system, enhances sexual desire and performance!, fights cancerous cells, slows down aging, promotes healthier skin, alleviates diabetes!, normalizes cholesterol levels, maintains healthy heart function, minimizes inflamation, improves circulation, prevents atherosclerosis, enhances visual acuity
• WOW!!
But………….
• Small print “none of these claims have yet been evaluated by the US FDA”
• “provides disease fighting benefits no Doctor wants you to know!”
Acai Berry Products
• 60 tablets for 28.95$
• Labelling!
Conclusions
Both goji and acai no doubt are both high on the ORAC scale. But not miracle cures!
The “magic” of cranberries
• Many people are allergic to antibiotics used to treat urinary infections
• Recent Harvard Study indicates that cranberries contain a compound that prevents E. Coli (Common cause of UI’s) form binding to the wall of the bladder
Mechanism of action
• Presently under study
• But looks like Proanthocyanodins present in cranberry juice are causing expression of types I and P “Adhesin” , thus preventing adhesion of E Coli.
• No drug reactions known with cranberry juice
A healthy way to start the day
Except……..
Beware the grapefruit!
• Juice/fruit inhibits the action of 2 enzymes that are required to break down/metabolize several drugs and make them effective.
• Including BC pills, cholesterol lowering statins, several antibiotics, Valium, Zoloft
• And possibly Viagra!
New Fads in Drinks: 2009
• Vitamin waters $2 for 591mL
• Enough Vit. C (150mg) (RDA~60mg)
• Some of B complex present; but not B1 (thiamine ) and B2 (riboflavin);B3-B6OK
• 120 calories per bottle ( how much sugar??)
• “non-essential ingredients” water, cane sugar, citric acid, veg juice (for colour), natural flavor
Hot Sellers in the Carleton Unicentre store!
• Many flavours and more on the way!