Notes
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Topics to be learn :
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Nutrition and nutrients :
Living things need nutrition for the following purposes :
- To obtain energy
- For the growth of the body
- To carry out day to day functions of the body
- To develop resistance against diseases.
For this nutrition, nutrients are required which are obtained through the food stuffs. Therefore food is required for the body for above purposes.
Carbohydrates, fats, proteins, vitamins and minerals are the main nutrients in the food.
Nutrients-Sources-Functions : 1-Carbohydrates : Our main need is of energy.. 2-Proteins : 3-Fats : 4-Vitamins : 5-Minerals :
Kilocalorie : Energy obtained from food is measured in the unit called kilocalorie. Growing children need about 2000 to 2500 kilocalories of energy.
Minerals : 1-Iron : 2- Calcium and Phosphorus : 3- Iodine : 4-Sodium and potassium :
Vitamins : There are two major types of Vitamins, i.e. water soluble vitamins and fat soluble vitamins.
Water soluble vitamins :
- Vitamin B complex (B1, B2, B3, B6, B9, B12) and Vitamin C dissolve easily in water. So they are called water soluble vitamins.
- Excess of these vitamins will not be stored in the body, but will be thrown out of the body. Hence, a regular supply of these vitamins is essential.
Fat soluble vitamins :
- These vitamins are insoluble in water but are soluble in fatty substances.
- Vitamins A, D, E and K are fat soluble vitamins.
- Excess of these vitamins will be stored in the body and will not be thrown out of the body.
Vitamins, their sources, functions and deficiency diseases : potatoes, deep yellow fruits and vegetables (inability to see in dim light), Xeroderma (dry skin) Muscle weakness / inefficiency growth, forgetfulness, slow movements and other citrus fruits, cabbage, tomatoes, green leafy vegetables. collagen, Health of gums, teeth, bones and skin meat, eggs, butter of the bones, causing pain and fractures) reproduction, skin disorders
Vitamins
Sources
Functions
Deficiency diseases
A
Carrot, milk, butter, dark green vegetables, sweet
Protects eyes. Helps to keep skin, bones and teeth healthy.
Night blindness
B1
Milk, fish, meat, cereals, nuts, pulses
Helps in proper functions of nerves and heart.
Beriberi (Nerve disorder),
B9
Deep green vegetables, papayas and kiwi
Growth of the body.
Anaemia, improper
B12
Meat, milk products
Formation of red blood cells
Anaemia
C
Amla, kiwi, oranges
Protection of body tissues. Formation of
Scurvy (bleeding of gums), thyroid malfunction, delay in healing of wounds.
D
Sunlight, milk, fish
Absorption of calcium and phosphorus, Health of bones and teeth
Rickets (softening
E
Wheat germ, green leafy vegetables, tender leaves, vegetable oils
Smooth functioning of Metabolism inside the cells, reproduction, maintaining efficiency of muscle cells.
Weak muscles, obstruction in
K
Green leafy vegetables, sprouted pulses, egg yolk. broccoli
Essential in blood clotting.
Excessive bleeding after an injury
Deficiency diseases :
- Scurvy, beriberi, pellagra, rickets are different types of diseases that are caused due to deficiency of vitamins in the diet.
- Casimir Funk was the scientist who discovered that beriberi is caused due to eating fully milled rice. He proposed the term vitamin.
- Some vitamins like vitamin C get destroyed during cooking as it is highly sensitive to heat and light. Therefore, certain food stuffs have to be eaten raw.
Probiotics :
- Useful microorganisms like those converting milk into yoghurt are called probiotics
- In the intestine too there are lakhs of such microorganisms which synthesise vitamins
Balanced diet : All that is consumed during a day is called diet. A diet with all the nutrients in adequate and balanced proportion is called balanced diet.
Importance of fibre in our daily diet :
If fibres are not in proper proportion in the diet, then there is a problem of constipation. The obesity is also caused due to lack of fibres in the diet. In order to keep the fibres in the food stuffs, they should not be overcooked. The peeling of fruits and vegetables should not be done. The flour should not be sieved. The husk in the flour gives lots of vitamins and fibre.
Significance of balanced diet :
Sources of balanced diet : The daily diet, including lunch and dinner should contain all the nutrients in the proper proportion. All these nutrients should be included as per the data shown in the food pyramid. Apart from having a balanced diet, we also need to exercise regularly to keep ourselves fit and healthy.
Fibre :
There should be sufficient amount of fibre in the daily diet. This helps to keep health in good condition.
Water :
Water is essential to run all the functions of the body. Therefore, adequate supply of water is needed. We get Water through milk, buttermilk, juices, sherbet, fruit juices and plenty of drinking water.
Malnutrition :
When the nutrients required for the proper functioning of the body are not obtained in desirable proportion, then malnutrition takes place. Imbalance or faulty diet or lack of food causes malnutrition. Similarly if over-intake of food is done, it causes over-nutrition. This is also a type of malnutrition. '
Junk food : Food which does not supply necessary nutrients but gives only unwanted calories is a junk food.
- The junk food is tasty, attractively packaged, oily, sweet and fried.
- This food does not supply us with any essential nutrients and thus it also causes malnutrition.
- Excess eating of junk food causes obesity. Chocolates, noodles, burgers, pizzas, chips, bottled soft drinks, snacks, fried foods like wadas and pakodas are all favourite and tasty items but they are not good for health as they do not supply any nutrients.
Avoiding obesity :
Adulteration of food :
Cheaper substances of low quality are added to the food to gain more profits.
Such substances are called adulterants and the mixing of adulterants is called food adulteration.
Adulterants can be poisonous and harmful to health. Adulterated food is unfit for consumption. Adulteration of food is an offence.
Food items Adulterants :