Over View Vitamins

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VITAMINS

do not provide energy (calories) but they areneeded for metabolism of energy,for biochemicalfunctions, to protect health, and for normal growthand activity of the body

function as coenzymes to activate enzymes



VITAMINS

The body needs vitamins in small amounts(microgram or milligram quantities) ±micronutrients

Vitamins are essential in the diet because theycannot be made by the body or they aresynthesized in inadequate amounts



VITAMINS

Vitamins were discovered a mere 100 years agoas scientists searched to identify what componentsin food prevented the development of deficiencydiseases such as scurvy (sailor¶s disease).

As knowledge of vitamin functions and

requirements grew, policies were enacted to enrichand fortify foodsFortification and enrichment have virtuallyeliminated vitamin deficiencies in the general

American population



ESK I OS D TH E IR LI E S TYLE

E skimos food habits causes hyper vitaminosisOf vit. and deficiency of Vit. C, but they managedto get vit. C by taking berries.



E N IC ME NT AN F TIFICATI N

E nrich: to add nutrients back that were lostduring processing, e.g., white flour is enrichedwith B vitamins that are lost when the bran andgerm layers are removedFortify: to add nutrients that are not naturallyfound in the food, e.g., milk is fortified withvitamin , and some breakfast cereals arefortified with vitamin



VITAMINS AN S UBI ITY

Vitamins are organic compounds that aresoluble in either water or fat; their solubilitydetermines how they are absorbed,transported through the blood, stored, andexcreted



TYP E S- FAT AN WAT ER S UB E VITAMINSFat-Soluble Vitamins

Properties:« Necessary for the function or structural integrity of

specific body tissues and membranes.« Can be retained in the body.« Apolar hydrophobic compounds that can only be

absorbed efficiently when there is normal fatabsorption.

W ater-Soluble Vitamins

Properties: ± Act as catalysts and enzyme cofactors in

metabolic processes and energytransfer.

± Are not stored in the body (excretedfairly rapidly) and must be replaced eachday.

± These vitamins are easily destroyed or washed out during food storage and



FAT ± SOLUBLEVITAMINS

VitaminPhysiologicImportance

Deficiency Excess RDAFoodsource

A(R etinol,

-carotene)

Component of light-sensitivepigments in eye

epithelial tissuemaintenance

regulation of gene expressionand celldiffentiation

Night blindnessXerophthalmiaAssociated with

Bitot's spots ,

keratomalacia,follicular hyperkeratosis

Carotenemia;Bleeding;

epatospleno-megaly (rare).

5,000IU

Greenvegetables, dairyproducts,eggs, liver



D(Calciferol)

initiates calciumabsorption inintestine andcauses bonemineralization

Promoteshardening of bones and teeth

Rickets(children)

steomalacia(adults)

ypercal-cemia leadingto metastaticcalcificationand renaldamage(rare).

400 IUfor adults

airyproducts,eggs,Fish liver oils.Synthesizedby sunlightaction onskin.

E(Tocopherols,

tocotrienols)

Antioxidant(Protects vitamins

A and C, fattyacids and redblood cellmembranes fromdestruction due tooxidation)

Possibly anemiaSerious

neurologicdysfunction(extremely rare)

Increasehemolysis of redblood cellsMuscular

dystrophy

None 15 IU(Men)12 IU(Women)

Margarine,seeds, greenleafyvegetables



K(Phylloquinone,menaquinones)

Blood clotting

R equired for synthesis of Prothrombin ( II)and clottingfactors VII, IX andX.

emorrhagic

diseaseypoprothrom-

binemia resultingin bleedingtendency

emolytic

anemia(rare)

No RD A.

300-500 mcgis consideredadequate

Green

leafyvegetables, liver;

Naturallyproducedbybacteria in

theintestine.



WATER - E

V ITAM I

V itaminPhysiologic

Importance

DeficiencyE xcess

R DA Foodsource

1(Thiamine)

catalyst incarbohydratemetabolism,nerve and heartfunction

Beriberi (wetand dry)

Wernicke'sencephalopathy

Korsakoff's

psychosis

Transientflushing,dizziness

0.5mg/1000caloriesconsumed

1.6 mgfor adults

rgan meats,pork, wholegrains,legumes,cereals,yeast, eggyolk



B2(R iboflavin,vitamin G)

essential part of enzyme systems

concerned withoxidation andreduction in livingcells.

Constituent of flavoproteins

*E ye irritation,

cornealvascularization,inflammation andbreakdown of skin cells

cheilosis,glossitis, angular

stomatitis

None. 0.55mg/1000caloriesconsumed.

1.6 mg for adults

Milk products,liver, eggs,

grains,legumes, darkgreenvegetables,cereals, fruit,yeast

* VIT. B2 DE FICI E NCY



B3(Niacin,Nicotinamide,Nicotinic acid)

xidation-

reductionreactions incellular respiration

Functionalpart of NA D and NA D P.

Pellagra (skin

andgastrointestinaldisorders,nerveinflammation,mentaldisorders)

Flushing due

to vasodilationoccurs withintravenousinjection (rare).

Abnormal liver function;cramps;

nausea

6.6 mg/1000

caloriesconsumed.

18 mg (male)13 mg

(female)

iver, lean

meats,poultry, fish,whole andenrichedgrainproducts,legumes



B5(Pantothenic

Acid)

E nergymetabolismneeded to form

coenzyme-A(CoA), and iscritical in themetabolism andsynthesis of carbohydrates,proteins , andfats.

For pyruvateoxidation andbiologicalacetylations

Fatigue, loss of coordination

Noneknown

0.5-10.0 mg for both adults andchildren isadequate

Milk products,liver, kidney,eggs, wholegrains,legumes; alsomade byintestinalbacteria.



B6(Pyridoxine,Pyridoxal,Pyridoxamine)

Aids in aminoacid metabolism,absorption; aidsin red blood cellformation; helpsbody use fats.

Coenzyme for decarboxylaseandtransaminasesystems

Convulsions,irritability, kidneystones

Glossitis;blepharitis;dermatitis;cheilosis;peripheralneuropathy;sideroblasticanemia.

Transientparesthesias

0.2mg/100mg

C N

1.8 mg(male)

1.5 mg(female)

Whole-graincereals,vegetables,meats



B12(Cyanocobalamin)

Nucleicacidproduction

Megaloblasticanemia (Perniciousanemia);

Subacutecombineddegeneration of spinal cord;peripheralneuropathy.

None. 3 mcg for adultsR ed meats,

iver, eggs,dairy products

and fish



C(Ascorbic Acid)

Collagenformation inteeth, bone, andconnective tissueof blood vessels

may help inresisting infection

absorption of iron , calcium,folacin

Ascorbic acid isa greatantioxidant

works withvitamin E as afree-radicalscavenger.

Scurvy(breakdown

of skin, blood

vessels, andteeth)impaired

woundhealing.*Vitamin C deficiency-

often resultssecondary tohyperparathy-roidism

None knownMinimal-

possibly urinary

calculi,gastrointestinalcomplaintsincludingdiarrhea,nausea andabdominalcramps

40-60 mg200 - 500

mg

per day(mostbeneficial)

Citrusfruits,green leafyvegetables, tomatoes



FolicAcid(Folacin)

Nucleic acidmetabolism

Megaloblasticanemia

(Perniciousanemia)

None.400 mcg for

adults

Whole-wheatfoods, green

vegetables,legumes, organmeats, fish,citrus fruits.



FAT-S UB E VITAMINS

Vitamins A, D , E , and KBecause they are stored in liver and adiposetissue, Vitamins A, D , E , and K do not need to be

consumed dailyVitamins A and D are toxic when consumed inlarge quantities over a long period



WAT ER -S UB E VITAMINS

B-complex vitamins and Vitamin Cnot generally stored in the body so a dailyintake is necessaryare considered nontoxic

adverse side effects, however, can occur from taking megadoses of certain water-soluble vitamins over a prolonged period



VITAMINS, D IE T AN D E A T

Although diets rich in fruits and vegetablesappear to be protective against chronicdiseases such as heart disease, cancer, andhypertension, it is not known what

components in them are responsible for thehealth benefits Antioxidant vitamins in foods are suspected of being beneficial



FREE R AD ICA S Are produced continuously in cells as they burnoxygen during normal metabolismProblem - they oxidize body cells and D NA in their quest to gain an electron and become stableThese structurally and functionally damaged cellsare believed to contribute to aging and varioushealth problems such as cancer, heart disease,and cataracts



ANTI XID ANTS AN D FREE R AD ICA S Antioxidants - substances that donate

electrons to free radicals to prevent oxidation Antioxidants protect body cells from beingoxidized (destroyed) by free radicals byundergoing oxidization themselves, which

renders free radicals harmlessVitamin C, Vitamin E , and beta-carotene aremajor antioxidants



VITAMINS AN D SUPP E ME NTS: M RE IS N TBE TTER

igh-dose supplements have not been proven to prevent disease andmay disrupt nutrient balances

Megadoses: amounts at least ten times greater than the RD A

In megadoses vitamins function like drugs, not nutrientsong-term safety has not been established

Some reports indicate that single-nutrient supplements may actuallyincrease, not decrease, health risks



FACTS AB UT F R UIT AN D VE GE TAB E INTAKE AM NG AM ER ICANS

When French fries and potato chips are excluded, Americans eat only about 3.6 servings of fruits andvegetables daily9 out of 10 teenage girls do not eat five servings of fruit and vegetables daily

Fruit and vegetable intake is declining--romainelettuce and bag lettuce are the only vegetables Americans are eating more of.

besity levels are lowest for people who eat themost fruit and vegetables



T B ST INTAK E F V E GE TAB E S AN D FR UITS:

E at at least five servings of fruits and vegetablesevery dayChoose wholesome, nutrient-dense foods over refined or processed foodsConcentrate on variety and color Make an effort to preserve the vitamin content of foods during storage and preparation

Avoid overcooking vegetablesMicrowave vegetables instead of boiling



T B ST INTAK E F V E GE TAB E S AN D FR UITS:

rder a vegetable when you eat outChoose 100% fruit juice at breakfast and instead of drinks, cocktails, ades, and/or carbonatedbeverages during the day

E at fruit for dessertMake fruits and vegetables more visible ± eave a bowl of fruit on the center of your table ± Keep fresh vegetables on the top shelf of the

refrigerator in plain view



BL I ESS



XEROPHTHALMIA



BITOT¶S SPOT



RICK ETS

.



BERIBERI



C HEILOSIS



G LOSSITIS



G LO SS IT IS



VIT. B2 DEFI C IENCY



NIAC IN DEFI C IENCY



PELLA G RA



VIT. B12 DEFI C IENCY



FOLI C AC ID DEFI C IENCY



S C URV Y



enough sir,Finish soon

your lecture !



Thank youFor your kind attention

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