FAT SOLUBLE VITAMINS Vitamins A D E K

FAT SOLUBLE VITAMINS Vitamins A, D, E, K • Functions • Effects of deficiency • Sources • Properties • RDA 1 © PDST Home Economics

VITAMINS • “VITAMIN” means “vital for life” * Nutrients required in very small amounts - mg or µg • VITAMINS are *Micronutrients which are necessary for everyday healthy functioning of the body 2

VITAMINS Two main categories Water soluble Fat Soluble B C A D E K

Water soluble Fat Soluble • Cannot be stored in body - • Can be stored in body regular supply needed regular supply not needed • Excess is excreted in • Can accumulate to toxic urine - no danger of toxic levels if large amounts levels ingested • Unstable to heat and light, leach into cooking liquids • Fairly stable at normal cooking temperatures

Vitamin A - Retinol and Beta. Carotene Retinol Beta-Carotene Named because of its concern with retina of eye Only found in animal foods Present with chlorophyll in plants, converted to Vitamin A in gut wall

Vitamin A – Retinol and Beta-Carotene Functions Effects of deficiency • Regulates growth • Retarded growth, malformed bones • Promotes healthy skin • Dry mucous membranes • Maintenance of • Xeropthalmia - dry eye healthy epithelial membrane tissues The moisturising vitamin! • Night blindness • Necessary for production of • Susceptibility to Rhodopsin - pigment infection in retina, helps eye adapt to dim light

Go for Color! • Vitamin A is what your body needs It gives you healthy bones and good strong teeth Beautiful hair that shines bright in the daylight Healthy eyes so you can see at night. . . • © 1999 Dole Food Company, Inc Now carotenes are real big news They give fruits and veggies colourful hues Eat yellow, orange, red and deep green 'Cause they're rich and loaded if you know what I mean

Vitamin A - Retinol and Beta. Carotene Sources Retinol - Cod liver oil, liver, dairy products, herring, egg yolk Beta-Carotene Dark green leafy vegetables, broccoli, carrots, deep orange fruits and vegetables Go for Color! Think Yellow, Orange, Red, Deep Green Now carotenes are real big news They give fruits and veggies colourful hues. .

Vitamin A - Retinol and Beta. Carotene Properties • Yellow fat soluble alcohol • Insoluble in water • Can be destroyed by oxygen, light and air • Some reduction in dehydration • Powerful antioxidant RDA 600 µg per day 90% of Vitamin A in the body is stored in the liver

Vitamin D - Calciferols Cholecalciferol The sunshine Vitamin! The sun activates Provitamin 7 dehydro cholesterol present in fat under skin Provitamin 7 dehydro cholesterol Cholecalciferol Ergocalciferol Formed by action of ultra violet light on fungi and yeasts Manufactured synthetically for use as vitamin supplement

Vitamin D -Calciferols Functions • Absorption and laying down of calcium and phosphorous in bones and teeth • Regulates calcium balance between bones and blood • Prevents rickets Effects of deficiency • *Rickets in children and *osteomalacia in adults * Conditions where bones are soft and cannot take weight of the body • **Osteoporosis **Bones become light, less dense and prone to fractures • Dental caries

Vitamin D -Calciferols Sources Sunlight conversion Fish liver oils Dairy products Oily fish Margarine

Vitamin D -Calciferols Probably the most stable of the vitamins Properties • Fat soluble • Insoluble in water • Stable to heat, acids, alkalis, oxygen • Unaffected by cooking or preservation RDA 7 -10µg per day

Vitamin E -Tocopherols Anti coagulants and anti oxidants Functions • Powerful antioxidant • May reduce risk of heart disease, stroke, cancer • Improves absorption of vitamin A Effects of deficiency • Deficiency is rare • Linked to conditions associated with malabsorption of fat • Nerve damage, loss of balance, lowered immune system

Vitamin E -Tocopherols Sources Wheatgerm Oatmeal Oils and animal fats Leafy greens Eggs

Vitamin E -Tocopherols Properties • Fat soluble • Insoluble in water • Stable to heat, unaffected by cooking or preservation • Acts as antioxidant, delays rancidity and oxidation • Damaged by alkalis and UV light RDA Based on polyunsaturated fatty acid intake

Sometimes called “Coagulation” vitamin Vitamin K - Napthoquinones Functions Effects of deficiency • Constituent of prothrombin which is necessary in blood clotting • Abnormal clotting, bleeding. • Deficiency is rare

Vitamin K - Napthoquinones Sources Dark green vegetables Liver Lean meat Eggs Manufactured by bacteria in intestine

Vitamin K - Napthoquinones Properties • Fat soluble • Insoluble in water • Stable to heat, unaffected by cooking • Destroyed by light, strong acids, alkalis RDA No established recommendation

Hypervitaminosis Excess vitamins A and D • Hypervitaminosis A - Excess Vitamin A is stored in the liver. In extreme cases can cause dry skin, enlarged liver, fatigue, hair loss, headaches, appetite loss, vomiting, risk of birth defects and miscarriage. • Hypervitaminosis D - More common in young children than adults. Results in high concentration of calcium in blood. Symptoms - nausea, mental confusion, vomiting and thirst.

Hand in Hand – How vitamins help each other • Vitamin E keeps Vitamin A from being destroyed in the intestines • Vitamin D enables the body to absorb calcium and phosphorous • Vitamin C helps folate build proteins • Vitamin B 1 works in the digestive system with niacin, pantothenic acid and magnesium