Food Nutrients, Vitamins : Controls our Body`s Physical Harmony and Growth

Food Pyramid

Pictures of all types of food Soures

FOOD NUTRIENTS:
A nutrient is any substance that is digested, absorbed and used to promote body function.These substances are:
CARBOHYDRATES
PROTEINS
FATS
VITAMINS
MINERAL SALTS
WATER

Many foods contain a number of nutrients, e.g. potaotes and bread are mainly carbohydrate, but both contain proteins
and some vitamins.Foods are described as carbohydrate and protein because they contain a higher proportion of one or the other.Fibre more correctly known as non starch polysaccharide (NSP), consist of indigestable material.It is not a nutrient , as it is not digested or absorbed, but it has may beneficial effects on digestive tract.

BALANCE DIET:

The diet is the selection of foods eaten by an individual. A balance diet is essential for health. It provide the appropriate amount of all nutrients in the correct proportions to meet the body requirements. An essential nutrient is a substance that cannot be made by the body and must therefore be included in the diet. The balance diet contains all nutrients required for health in appropriate proportions and is normally achieved by eating a variety of foods. If any nutrient is eaten excess, or is defiecient, health may be adversely affected. For example, a high energy diet can lead to obesity, and an iron-deficient one to anaemia.

A balance diet is important in maintaining a healthy body weight and can be assessed by calculating Body Mass Index (BMI).

Body Mass Index:
Calculation:
                                              Weight (Kg)
Body Mass Index (BMI) = -------------------------------
                                              Height (m2)

Interpretation of BMI:

<16          Severely Underweight

16- 19       Underweight

20 - 25      Normal range

26 -30       Overweight

31 -41       Obese

>41          Severely Obese

Daily energy requirements depend on several factors including basal metabolic rate, age , gender and activity level.

Dietry Carbohydrates, fats and proteins are the principal energy sources and fat is the most cencentrated form. Dietary energy is correcly expressed in Joules and Kilojoules(kj) although the older terms calories and kilocalories (kcal or cal) are also still widely used in UK.

Recommendations for daily food intake sort foods or similar origins and nutritional values into food groups and advise that a certain number of serving from each group be eaten daily. If This plan is followed, the resulting dietry intake is likely to be well balanced. The Five main groups are:

Bread , Rice , Cereal and pasta.
Fruit and vegetables.
Meat and Fish
Dairy Products, e.g. milk and cheese
Fats oils and sweets.

Bread , Rice , Cereal and pasta.
Most ( 50 - 60%) of the daily energy requirements should come from these sources. In practice this means eating 6-11 servings from this food group  every day. These food contain large amounts of complex carbohydrates, which provide sustined energy release, as well as fibre.

One Serving = One Slice of bread, one small bread roll, Two Large crakers, 25 g cereal.
Fruit and Vegetables:
It is recommended that at least five portions should be eaten daily.Fruit and vegetables are high in vitamins,minerals
and fibre,and (provided they have not been, for example fried) are low in fat.
  
One serving = A medium apple, orange and banana; 100g cooked/raw vegetables or tinned/fresh/cooked fruit;
                       one wedge of melon; 125 ml fruit or vegetable juice.

 

 

Dairy Products:
These group includes milk, cheese and yoghurt, and is high in calcium and vitamins. 2-3 servings per day are recommended dairy foods are often high in fat.



1 Serving = 250 ml milk or yoghurt ; 50 g cheese.

Meat fish and alternatives:
Current dietary habits in developed countries mean that too much of the daily energy requirements are met from this group of foods (Which includes eggs and nuts) and from high fat foods. although these foods are high in protein and some vitamins and minerals only 2-3 servings daily are recommended because they have a high fat content.

One serving = One egg, 30 g peanut butter, 80 g lean cooked meat.

Fats oil and sweets:
These high energy foods contain little other nutritional value and should be used sparingly, if at all. Certain groups of people may require a diet different from the principles outlined above.For example, pregnant and lactating women have



higher energy requirements to support the growing baby and milk production.Menstruating women need more iron in their diet than non-mentruating women need more iron in their diet than non menstruating women to compensate for blood loss during menstruation.Babies and growing children have higher energy requirments than adults because they

have higher growth and metabolic rates. In some gastrointestinal disorders their is intolerance of certain
foods, which restricts that person`s dietary choices

FUNCTIONS OF CARBOHYDRATES:
Provision of rapidly available energy and heat glucose is the main fuel molecule for energy production.
Protein sparing; i.e. when there is an adequate supply of carbohydrate in the diet, protein does not need to be used
            to provide energy and heat.
Provision of a store of energy when carbohydrate is eaten in excess of the body`s needs as it is converted to:
            Glycogen- as a short term energy store in the liver and skeletal muscle.
            Fat and deposited- in the fat depots, e.g. under the skin.

Carbohydrate Sources

FUNCTIONS OF PROTEINS:
Amino acids are used for growth and repair of body cells and tissues.
Synthesis of enzymes, plasma proteins, antibodies and some hormones.
Provision of energy.Normally a secondery function, this becomes important only when there is not enough carbohydrate in the diet and fat stores are depleted.

Protein Sources

Protein Sources

FUNCTIONS OF FATS:
Provision of most concentrated source of chemical energy and heat.
Support of certain body organs, e.g. the kidneys, the eyes.
Transport and storage of the fat-soluble vitamins: A,D,E,K.
Constituent of nerve sheaths and sebum, the secretion of sebaceous glands in the skin.
Formation of colesterol and steroid hormones.
Storage of energy as fat in adipose tissue under the skin and in the mesentery, especially when eaten in excess of requirements.
Insulation- as a subcutenous layer it reduces heat loss through the skin

Sources of Fat

Vitamins: 

Vitamins are chemical compounds, required in very small quantities, which are essential for normal metabolism and health. They are found widely distributed in food and are divided into two main groups :



Fat soluble vitamins: A,D, E and K.

List Of Fat Soluble Vitamins

Water soluble vitamins: B Complex, C

List of Water Soluble Vitamins

CALCIUM:
This is found in milk,cheese, eggs, green vegetables and some fish.An adequate supply should be obtained from a normal,well-balanced diet, although requirements are higher in pregnant women and growing children.99% of body calcium is found in the bones, where it is an essential structural component.Calcium is also involved in coagulation of blood and muscle contraction.

Sources of Calcium Specially In Milk and other Dairy Products

IRON:
Iron as a soluble compound, is found in liver, kidney,beef, egg yolk, wholemeal bread and green vegetables.In normal adults about 1 mg of iron is lost from the body daily.The normal daily diet contents more, i.e. 9 to 15 mgt but only 5-15%
of intake is absorbed.Iron is essential for the formation of haemoglobin in red blood cells. It is also neccessory for oxidation of carbohydrates and the synthesis of some hormones and neurotransmitters.

Sources of Iron

IODINE:
Iodine is found in salt water fish and in vegetables growing soil containing iodine.In some part of the world where iodine is deficient in soil,very small quantities are added to table salt to prevent goitre.Daily iodine requirement depends upon metabolic rate.It is essential for the formation of thyroxine and triiodothyronine, two hormones secreted by the thyroid gland.

Iodized Salt Have Good source of Iodine needed for body

POTASSIUM:
This substance is found widely distributed in all foods especially fruit and vegetables and intake usually exceeds potassium requirements.
Muscle contraction.
Transmission of nerve impulses.
Maintenance of electrolyte balance in the body.


SODIUM:
Sodium is found in most foods, espcially fish, meat, eggs, milk, most processed foods and also added during cooking or as table salt.Intake of sodium chloride usually exceeds requirements and excess is excerted in the urine.

formula of Table Salt Is Nacl  (good Sodium Source)

Muscle contraction.
Transmission of nerve impulses along axons.
Maintenance of electrolyte balance in the body.

POTASSIUM:
This substance is found widely distributed in all foods especially fruit and vegetables and intake usually exceeds potassium requirements.
Muscle contraction.
Transmission of nerve impulses.
Maintenance of electrolyte balance in the body

Fruits and Vegetables are the main source of Potassium

Fruit Juices