From DT Online
|Vitamins are needed by the body in small amounts, The body cannot make vitamins and so they must be supplied by food. Two Groups of vitamins exist classified according to the substance in which they dissolve.
Bacteria in the intestine can produce some of the vitamins in the B complex but not enough to meet the body's needs.
|Vitamin A is necessary for growth and the maintenance of healthy skin. It prevents infection and dryness of mucous membranes in the throat, bronchial, digestive and excretory systems. It is also needed to make 'visual purple', helping the eye to see in dim light.
Good food sources include oily fish, dairy foods and margarine. Vitamin D can also be supplied by fruit and vegetables.
|Vitamin B complex
Good sources of Vitamin B include wholegrain cereals, yeast, yeast extract, milk and eggs.
|Vitamin C helps bind body cells together, helps the body absorb iron. It helps keep teeth and bones strong, maintains the lining of the digestive system and also helps in production of blood.
Good sources of vitamin C include rosehips and blackcurrants. Other sources include citrus fruits and beansprouts.
|Vitamin D is essential for healthy bones and teeth. It promotes the absorption of minerals which prevent soft bones.
Good sources of Vitamin D include liver, fish oil and oily fish. Other sources include egg yolks, dairy produce and margarine.
|The function of vitamin E remains unclear, and deficiency diseases are virtually unknown as the vitamin is so widely available.
Good sources of vitamin E are abundant and include lettuce, peanuts, seeds, wheatgerm oil, milk and egg yolk.
|Minerals are elements needed by the body other than carbon, hydrogen and oxygen.
|Carbohydrates are produced mainly by plants during photosynthesis. They fall into two categories:
Carbohydrates contain the 3 elements: carbon, oxygen and hydrogen.
Carbohydrates are an important energy source, acting as a protein sparer. Allowing protein to be used for body growth and repair and maintenance. Sugar is, however, a source of empty energy providing no other nutrients and it is better to gain energy from other foods. Excess carbohydrate is converted into fat and stored under the skin - snack foods in the diet may cause obesity if eaten in large amounts. Starch is a good energy source, containing other nutrients and dietary fibre. It also serves to prevent over eating - starchy foods are bulky and therefore filling.
|Protein must be obtained from foods as the body cannot make the essential amino acids.
The molecules of protein join to form amino acids which are linked together in a chain.
There are at least 22 different amino acids.
|Fat is available as hard or soft fat. Animal fats are normally hard. Vegetable fats or plant fats are usually soft and sold in the form of oil. Fats are composed of the elements carbon, hydrogen and oxygen which combine to form fat molecules. Fatty acids are both saturated (predominantly solid at room temperature) and unsaturated (existing in oils).
N.B. fats in food serve many functions but too much fat in the diet can increase the risk of heart disease.
|Dietry Fibre comprises the indigestible parts of food which remain in the large intestine after digestion. Fibre makes up the plant cell walls of food. Tthe fibrous wrapping surrounds the nutrients contained in the food.
Sources of dietry fibre include bran in breakfast cereals, wholemeal flour, wholegrain cereals, root vegetables, peas, beans and dried fruit.