chapters 10 & 11 the vitamins vitamins vitamins – organic nutrients required in trace amounts...

Chapters 10 & 11

THE VITAMINS

Vitamins

• Vitamins – organic nutrients required in trace amounts

• Essential to the regulation of body processes

• Noncaloric• Divided into 2 groups based on

solubility: Fat-soluble & Water-soluble

The Fat-Soluble Vitamins

Copyright 2005 Wadsworth Group, a division of Thomson LearningCopyright 2005 Wadsworth Group, a division of Thomson Learning

Vitamin A• Other names

– Retinol– Retinal– Retinoic acid– Precursors are carotenoids such

as beta-carotene made by plants


Vitamin A & Beta-Carotene


Vitamin A• Chief functions in the body

– Vision– Maintenance of cornea, epithelial

cells, mucous membranes, skin– Bone and tooth growth– Reproduction – Immunity– Beta-carotene as an antioxidant

(may help prevent cancer & heart disease)


Beta-CaroteneThe color of Vitamin

A foods - spinach and other dark leafy greens; broccoli, deep orange fruits (apricots, cantaloupe) and vegetables (squash, carrots, sweet potatoes, pumpkin)


Vitamin A• Significant sources

– Retinol: fortified milk, cheese, cream, butter, fortified margarine, eggs, liver

• 2001 RDA– Men: 900 g/day– Women: 700 g/day


Vitamin ADeficiency symptoms

– Night blindness - leading cause of childhood blindness in world

– corneal drying (xerosis) – triangular gray spots on eye (Bitot’s spots)– softening of the cornea (keratomalacia)– corneal degeneration and blindness

(xerophthalmia)– Impaired immunity (infections)– Plugging of hair follicles with keratin, forming

white lumps (hyperkeratosis)


Vitamin A• Upper level for adults: 3000 g/day Excess preformed may be toxic but

excess beta-carotene is not toxic• Acute toxicity symptoms

– Blurred vision– Nausea, vomiting, vertigo– Increase of pressure inside skull, mimicking

brain tumor– Headaches

• Chronic toxicity symptoms– Increased activity of osteoclasts causing

reduced bone density– Liver abnormalities– Birth defects


Vitamin D• Other names – the “sunshine”

vitamin– Calciferol– 1,25-dihydroxy vitamin D

(calcitriol)– Animal version: vitamin D3 or

cholecalciferol– Plant version: vitamin D2 or

ergocalciferol– Precursor is the body’s own

cholesterolCopyright 2005 Wadsworth Group, a division of Thomson Learning

Copyright 2005 Wadsworth Group, a division of Thomson Learning

Vitamin D

• Chief functions in the body– Mineralization of bones (raises

blood calcium and phosphorus by increasing absorption from digestive tract, withdrawing calcium from bones, stimulating retention by kidneys)


Vitamin D

• Significant sources– Synthesized in the body with the

help of sunlight– Fortified milk, margarine, butter,

cereals, and chocolate mixes– Veal, beef, egg yolks, liver, fatty

fish (herring, salmon, sardines) and their oils


Vitamin D

• 1997 adequate intake (AI)– 19-50 years: 5 g/day– 51-70 years: 10 g/day– more than 70 years: 15 g/day

• Upper level for adults:50 g/day


Vitamin D• Deficiency symptoms: rickets in

children– Inadequate calcification, resulting in

misshapen bones (bowing of legs)– Enlargement of ends of long bones

(knees, wrists)– Deformities of ribs (bowed, with

beads or knobs)– Delayed closing of fontanel, resulting

in rapid enlargement of head


Vitamin D

• Deficiency disease in children– Rickets


Vitamin D

• Deficiency symptoms in adults: -Osteomalacia

-Loss of calcium, resulting in soft, flexible, brittle , and deformed bones

– Progressive weakness– Pain in pelvis, lower back, and

legs


Vitamin D

• Toxicity symptoms– Elevated blood calcium– Calcification of soft tissues

(blood vessels, kidneys, heart, lungs, tissues around joints)

– Frequent urination


Vitamin E• Other name: alpha-tocopherol• Chief function in the body

– Antioxidant (stabilization of cell membranes, regulation of oxidation reactions, protection of polyunsaturated fatty acids and vitamin A) effect in lungs, protection against heart disease, helps relieve fibrocystic breast disease


Vitamin E


Vitamin E

• 2000 RDA–Adults: 15 mg/day

• Upper level for adults:1000 mg/day

Vitamin E

• Significant sources– Polyunsaturated

plant oils (margarine, salad dressings, shortenings)

– Leafy green vegetables, wheat germ, whole grains, liver, egg yolks, nuts, seeds


Vitamin E• Easily destroyed by heat and

oxygen• Deficiency symptoms

– Red blood cell breakage (erythrocyte hemolysis)

– Nerve damage

• Toxicity symptoms– Interfers with blood clotting &

augments the effects of anticoagulants


Vitamin K

• Other names– Phylloquinone– Menaquinone– Menadione– Naphthoquinone


Vitamin K• Chief functions in the body

– Synthesis of blood-clotting proteins and bone proteins that regulate blood calcium


Vitamin K

• 2001 AI–Men: 120 g/day–Women: 90 g/day

Vitamin K• Significant

sources– Bacterial

synthesis in the digestive tract

– Liver– Leafy green

vegetables, cabbage-type vegetables

– MilkCopyright 2005 Wadsworth Group, a division of Thomson Learning

Copyright 2005 Wadsworth Group, a division of Thomson Learning

Vitamin K• Deficiency symptoms:

- Hemorrhagic disease (blood fails to clot)

- Can occur with long-term use of antibiotics & newborns (Vit. K usually given at birth)

• Toxicity symptoms:- Causes RBC hemolysis & jaundice

- Interferes with effectiveness of anticoagulants


chapters 10 & 11 the vitamins vitamins vitamins – organic nutrients required in trace amounts...

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betacarotene copyright

color of vitamin

gday copyright

vitamin d chief functions

vitamin d significant

cholesterol copyright

pumpkin copyright