home economics form 3 vitamins€¦ · home economics form 3 a deficiency in the b-group vitamins...

Home Economics Form 3

Vitamins

The word vitamins is derived from the word “vita” which means life, hence one can conclude

that vitamins are essential for good health and growth. Although needed in small amounts, their

intake is crucial. Sometimes an RDA (Recommended Dietary Allowance) or RNI (Reference

Nutrient Intake) is given for vitamins, which is a quantity of nutrient intake that is required to

maintain good health in almost all people.

Vitamins are divided into TWO groups:

Water Soluble Vitamins:

When consuming foods that are rich in

water-soluble vitamins, these

vitamins are not easily stored in our

body. They travel directly through our

bloodstream. Any excess of such

vitamins are lost from the body in the

form of urine. Therefore water-

soluble vitamins need to be replaced

often. Deficiency rarely occurs and

excess is difficult to happen since they

are not stored in the body.

Fat Soluble Vitamins:

When we consume foods that are rich

in fat-soluble vitamins, these are

stored in the fat tissues of the body

and liver. They are stored in our body

fat until our body needs them and

special carriers in our body take them

to where they are needed. Some of

these vitamins are stored for a few

days only, while some are stored for

up to 6 months, hence frequent intake

is not necessary. Deficiency and

excess are both feasible to happen. B*

C A

D E

K


Water Soluble Vitamins

• The water-soluble vitamins include vitamin C and the B-group vitamins.

• They dissolve in water, and therefore can be dissolved (leached out) in cooking water

when fruits and vegetables are boiled, and also during processing.

• They are regularly excreted in urine so foods rich in these vitamins need to be eaten

frequently since they cannot be stored in the body.

Functions:

✓ Helps to prevent colds,

✓ Prevents scurvy (gums become swollen and red and they bleed easily and teeth are lost),

✓ Helps with the healing of wounds,

✓ Helps the body absorb iron,

✓ Is an important antioxidant, together with Vitamin A (in the form of beta-carotene) and

Vitamin E.

Sources of Vitamin C:

✓ Citrus fruits such as lemons and oranges,

✓ A variety of fruits including papaya and blackcurrants,

✓ Tomatoes,

✓ Red and green peppers and chilli peppers,

✓ Green vegetables especially kale and broccoli.

Vitamin C (Ascorbic Acid)


Deficiency of Vitamin C in the Body:

✓ Scurvy: mouth and gums become sore and teeth loosen,

✓ Bones heal very slowly,

✓ Walls of blood vessels weaken and break in some places, this causes red spots

(haemorrhages) under the skin,

✓ General weakness: fatigue, irritability, muscle pain, weight loss,

✓ Iron-deficiency anaemia (caused by lack of iron) since iron is not absorbed properly

without vitamin C.

Suggestions to include Vitamin C in the Diet:

✓ Eat plenty of fresh fruits and vegetables. Try to eat at least 5 portions of fruit and

vegetables every day,

✓ Have a glass of orange or other home-made juice for breakfast,

✓ Have plenty of salads.

Vitamin C is very easily destroyed by heat,water, exposure to air and alkali e.g. bicarbonate of soda. Use fruit and vegetables uncooked where possible, and when you cook them, follow these rules:

1. Use them as soon as possible after they have been packed and do not store them for too long unless you freeze them; the fresher the fruit/vegetables is, the higher the vitamin C content.

2. Cut with a sharp knife to reduce damage to cell walls. 3. Do not leave them to soak, otherwise the Vitamin C will leach out into the water. 4. Avoid boiling to cook vegetables, opt for steaming instead. If you do boil them, put

vegetables in a small amount of boiling water and use the cooking water for gravy or home-made stock.

5. Do not keep vegetables hot for a long time; eat as soon as possible when they are cooked.


The B-Group Vitamins are also water soluable, which means that they cannot be stored in the

body, and so, needed on a daily basis. The B-Group Vitamins are needed for many body

processes and requirements increase during pregnancy and lactation.

The main functions of B-Vitamins are:

1. They are needed to make use of the energy in foods (they help convert food into energy).

2. They are needed for nerve, brain and muscle function.

3. They are needed for the formation of red blood cells.

B Vitamins

Vitamin B1: Thiamine

Vitamin B2: Riboflavin

Vitamin B3: Niacin

Vitamin B6: Pyridoxine

Vitamin B12: Cobalamin

Folate or Folic Acid

(B9)

The B Group Vitamins


A deficiency in the B-Group Vitamins is very rare, especially if people eat a varied diet. This is

because they are found in small amounts in a variety of foods, e.g. potatoes, wholemeal flour,

cereals, bread, yeast, pork, bacon, liver, kidney and nuts.

Stability in Food Preparation:

Most of the B-Vitamins, except Niacin, are sensitive to heat so can be easily lost by cooking and

processing, they can also be easily lost by dissolving in cooking water. Thiamin (B1) and Vitamin

C are the most easily lost of all vitamins.

Functions :

✓ Helps release energy from nutrients into every cell of the body,

✓ It is required for normal growth of children,

✓ Required for nerves to function properly.

Deficiency:

✓ Depression, irritability, loss of memory, anxiety,

✓ Retarded growth in children,

✓ Beri-beri: weight loss, exhaustion, and weak muscles.

Recipe Ideas:

Lentils Soup, Weetabix with Milk and Fruit, Sunflower Seed Bread, Lentil Patties

Vitamin B1 (Thiamin)


Functions:

✓ For normal growth,

✓ Helps release energy from food to cells,

✓ Required in the body’s use of carbohydrate.

Deficiency:

✓ Retarded growth,

✓ Skin wounds, dermatitis (skin disorder, eye problems),

✓ Tongue, mouth, and lips become sore.

Recipe Ideas:

Stuffed Eggs, Pork with Mushroom Sauce, Stuffed Mushrooms, Egg Salad

Functions:

✓ Release of energy from food especially carbohydrate food.

Apart from the Dietary sources of the B-Group Vitamins, Niacin can be made in the body from the

amino-acid tryptophan.

Vitamin B2 (Riboflavin)

Vitamin B3 (Niacin or Nicotinic Acid)


Deficiency:

✓ Pellagra: this condition causes dermatitis, dementia (memory loss, confusion and

depression), and diarrohea (abdominal discomfort, loss of appetite, loose and

frequent stools).

Recipe Ideas:

Tuna Salad, Sheperd’s Pie, Potato Soup, Date Pie

Functions:

✓ Helps produce other body chemicals like insulin, haemoglobin, and antibodies,

✓ Helps maintain brain function and form red blood cells,

✓ Vital in chemical reactions of proteins and amino acids.

Functions:

✓ Helps prevent certain forms of anaemia,

✓ Helps in cell division,

✓ Important for nervous system,

✓ Works closely with Folate to form red cells.

Vitamin B6 (Pyrodoxine)

Vitamin B12 (Cobalamin/Cyancobalamin)


Unlike other B-Vitamins which are found mostly in plant-based foods, Vitamin B12 sources are

found in useful amounts in animal foods such as liver, fish, meat, eggs, milk and dairy products,

and fortified breakfast cereals. Hence vegans may have an insufficient intake, and therefore,

Vitamin B12 deficiency is common among vegetarians and even more in vegans.

Deficiency:

1. Megaloblastic anaemia, where the red blood cells become enlarged and cannot give up

their oxygen properly to the body cells,

2. Neurological problems: epilepsy, Alzheimer disease and other dementias.

Recipe Ideas:

Marinara Pasta, Grilled Beef Liver with Onion Sauce, Custard, Bread Pudding

Functions:

✓ For normal growth,

✓ For the formation of red blood cells,

✓ For the release of energy from food,

✓ Helps prevent Neural Tube Defects.

Vitamin B9 (Folic Acid/Folate)


Neural tube defects are birth defects of the brain, spine, or spinal cord. This happens in

the first month of pregnancy, often before a woman even knows she is pregnant. The two

most common neural tube defects are spina bifida and anencephaly.

Apart from B-group common food sources, Folate is found in green leafy vegetables, brussels

sprouts, peas, bananas, grapefruit, oranges, and pulses.

Pregnant women and those planning a pregnancy are advised to take sufficient amounts of

Folate; doctors may in fact prescribe Folate supplements. This is because since Folic acid helps

prevent Neural Tube Defects (NTD), it may reduce the possibility of a child being born with

NTD.

Deficiency:

✓ Retarded growth,

✓ Megaloblastic anaemia,

✓ In pregnancy, insufficient intake may lead to a baby with Spina Bifida (spinal cord defect)

causing permanent disability.

Recipe Ideas:

Spinach Pie, Broccoli Soup, Broccoli Lemon Pasta, Bean Soup


Fat Soluble Vitamins

The fat-soluble vitamins are Vitamins A, D, E and K. They are fat-soluble which means that

they are found in fatty foods rather than watery foods. They dissolve in fat and can be stored

in the body, usually in the fat tissue (or adipose tissue) and liver.

Vitamin A found in plant foods is called beta-carotene. This gives plants their yellow/orange

colour. In the body beta-carotene is converted to retinol. Vitamin A found in animal foods is in

retinol form and hence does not require conversion.

Functions:

1. Vitamin A is needed for the retina of the eye to be able to see in dim light- for night

vision,

2. For the normal growth of children,

3. For good, healthy skin and eyes.

Sources:

✓ In plant foods: e.g. carrots, spinach, cabbage,apricots and peaches (beta-carotene),

✓ In animal foods: e.g. milk, cheese, eggs, margarine, and oily fish such as herrings and

sardines (retinol).

Deficiency:

✓ Night-blindness and in severe cases even total blindness,

✓ Retarded growth in children, especially in poor countries,

✓ Skin and body tissues become dry and infected, and resistance to disease is reduced.

Vitamin A (Retinol or Beta Carotene)


Excess of Vitamin A:

✓ Too much vitamin A is harmful as excess may lead to liver and bone damage.

✓ Vitamin A is stored in the liver, Therefore the liver is a rich source of Vitamin A.

✓ Pregnant women are advised NOT to eat liver because it contains high amounts of retinol

which could lead to damage and defects in the unborn baby. Beta-carotene does not

cause harm in this way, so it advisable for pregnant women to eat plenty of fresh fruits

and vegetables, in order to received the extra vitamin A that they need.

Functions:

✓ Vitamin D is needed for the proper formation of bones and teeth,

✓ It helps to promote the absorption of the minerals calcium and phosphorus.

Sources:

✓ Liver and fish-liver oils,

✓ Oily fish such as herrings and sardines,

Vitamin D


✓ Sunlight is also an important source. When the body is exposed to the ultra-violet rays

of the sun, a substance under the skin is converted to cholecalciferol, which is stored in

the liver. Most people make enough vitamin D from the action of sunlight on their skin so

no RNI (Recommended Nutrient Intake) is given.

Deficiency:

✓ Absorption of calcium and phosphorus from the small intestine is reduced, so there is

insufficiency to maintain the strength of teeth and bones. The bones become weak and

the legs may bend, the ends of the limb bones become enlarged and the skull becomes

fragile. This disease is called rickets and mainly effects children.

✓ The adult form of rickets known as osteomalcia may occur, where the bones become very

weak and may fracture easily even after a minor fall.

✓ Growth of children is retarded.

Excess of Vitamin D:

✓ Vitamin D is stored in the body. Most people get enough from sunlight especially in

countries like Malta. Too much Vitamin D, perhaps from Vitamin supplement is

dangerous, because it results in an excess absorption of calcium in the blood. This extra

calium will then be deposited in the lungs and kidneys and may cause death.


Functions:

✓ Vitamin E is a very effective antioxidant. A diet rich in antioxidant vitamins helps to

reduce the risk of heart disease and cancer.

Sources:

✓ From animal sources: milk, dairy products, and egg yolk

✓ From plant sources: mainly found in seeds and vegetable oils particularly that coming

from sunflower.

Deficiency:

✓ Deficiency of Vitamin E is rare, but in premature babies a deficiency may cause an

increased breakdown of red blood cells and also tissue damage.

✓ Like all other fat-soluble vitamins, people who cannot absorb fat properly may have

problems too.

Vitamin E (Tocopherol)


Functions:

✓ Assists in coagulation of blood to enable it to clot properly after an injury.

Sources:

✓ From animal sources: liver and smaller amounts in milk, meats, and eggs,

✓ From plant sources: green leafy vegetables especially spinach and the cabbage family,

✓ Smaller amount are also found in cereals, fruits and vegetables.

Vitamin K (Phylloquinone)


An antioxidant means that the vitamin can reduce the harmful effects of ‘free radicals’ the body

produces . Free radicals are highly reactive molecules that when they accumulate, they can

damage body cells by making our body more prone to cancer and other diseases. People who

eat large amount of fruits and vegetables are less likely to develop some forms of cancer and

CHD (Coronary Heart Disease) since anti-oxidants are mainly found in fruit and vegetables.

Vitamins as Antioxidants

Vitamin A Vitamin C

Vitamin E


Vitamin content in food especially Thiamine (Vitamin B1) and Vitamin C is affected by various

factors such as:

Heat/Cooking:

✓ High temperatures like that during cooking causes water-soluble

vitamins to be destroyed.

Time:

✓ If food is left for a long time, oxidation (effect of oxygen on food)

causes the vitamins to be destroyed.

*Remember! Buy local foods as foreign ones would have a lot of travelling

time, hence vitamin content would be reduced.

Preparation:

✓ Do not cut food in very small pieces as surface area will be increased and so exposure to

air increases (effect of oxidisation).

✓ Do not leave food in water for a long time because water-soluble vitamins will be lost in

water.

Preventing vitamin loss while preparing, cooking and serving food

Effects of Heat (Cooking)

Storage Time


✓ Cut food with a very sharp knife rather than a blunt one as blunt knifes will destroy much

more cells (leafy vegetables should be cut with your hands).

Cooking:

✓ Cook food with the least amount of water such as steaming or shallow frying. If boiling,

use the liquid for soups and gravies as these will contain the water-soluble vitamins lost

from food.

✓ Use a pressure cooker to cook food since it will cook faster and so less vitamins will be

lost.

✓ Keep the lid on while cooking food because this will help food to cook faster and so less

vitamins will be lost.

Serving:

✓ Serve immediately after it is cooked so that the effect of oxidation on food is minimised.

✓ Serve raw if possible.

home economics form 3 vitamins€¦ · home economics form 3 a deficiency in the b-group vitamins...

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