All organisms have a number of requirements to survive, grow and remain active.0 They include air, water and food. No organisms can survive for long without ,One of the several things that are common to all living beings is that they all need food to survive, remain healthy and to carry out various activities. Humans are no exception to this.
Food contributes to our physique ,effectiveness and emotional stability.
FUNCTIONS OF FOOD
- Every organisms including humans needs energy. Energy enables us to move, ,and reproduce.
- Food promotes growth ,supplies energy furnishes nutrients for the repair of body parts.
- Every breath, every thought ,every movements wears out some portion of our body.
- Various vital processes remove the worn out and useless cells.
- our body has to carry different functions. Different functions require different materials.
- Even if we get enough food to fill our stomach .We can be unhealthy .This is because we don’t get all essential elements from just one type of food. Hence ,we need to eat different kinds of food to get all the nutrients required for our body.
Constituents Of Food
- ⦁ Food constituents nourishing substances called nutrients.
⦁ They keep our body fit and active.
⦁ Different types of food contain different nutrients essential for our body.
Major constituents of food
⦁ Carbohydrates and lipids [Energy food].
⦁ Proteins [Body building food].
⦁ Vitamins and minerals [Protective food].
Carbohydrates and lipids:
⦁ All our activities require energy.
Our energy supply comes mainly from cereals.
⦁ Sugar, jaggery, whole grains, nuts kinds of fruits and potatoes contain large quantity of carbohydrates.
⦁ They are the compounds made of carbon, hydrogen and oxygen.
⦁ We also get energy from oils, butter and ghee.
⦁ Nuts and meat also contain fair quantity of oils and fats.
⦁ We can say oils and fats as lipids.
⦁ They serve as concentrated energy food.
⦁ Carbohydrates on digestion turn into glucose. Glucose gets into blood.
⦁ We should take carbohydrates in moderate quantity.
Functions and principal sources of carbohydrates
⦁ The regulation of sugar in the blood stream ensures supply of carbohydrates to every .
⦁ Complex carbohydrates such a cellulose are excellent source of fibre.
⦁ Fruits, dairy products, jaggery, sugar and vegetable provide simple carbohydrates.
⦁ A person with more Physical activity needs more carbohydrates.
⦁ Unused carbohydrates in the body are stored up as fats.
⦁ Excessive collection of fats in the body may result in overweight and obesity.
⦁ It is necessary to include carbohydrates in our diet.
Functions and principals sources of lipids
⦁ Lipids consists of made of carbon, hydrogen and oxygen.
⦁ They are insoluble in water.
⦁ There are several types of lipids including oils and fats.
⦁ Lipids help in brain functioning, smooth movement of joints, clotting of blood and energy production.
⦁ Some lipids helps to bring down inflammation within the body and lubricate the joints.
⦁ Our body makes some lipids some we get from our diet.
⦁ Fat helps the body to absorb and to move the vitamins A, D, E, and K through the bloodstream.
⦁ Lipids store energy and hence help in energy production.
⦁ More fats are not good for health.
⦁ Most fats come from animal sources like cheese, butter, whole milk, ice cream, cream, fatty means, coconut and palm oils.
Functions and principal sources of proteins
⦁ Proteins are large, complex molecules that play many critical roles in the body.
They are involved in all functions.
⦁ There are varieties of proteins, which are typically formed from a set
Of 20 simple compounds called Amino Acids .
⦁ Amino acids must be a part of our diet as they are not synthesized in ou body.
⦁ Most amino acid molecules include atoms of carbon(C), hydrogen (H), a carboxyl group(-COOH) and an amino group (-NH2).
⦁ Some proteins are involved in structural support, some in body .
⦁ There is an enzyme called pepsin. It plays an important role in digestion. It works in the stomach to break down proteins in food.
⦁ Another enzyme called lactase. It breaks down the sugar present in the milk.
⦁ These are Messenger proteins.
⦁ Insuline helps in the metabolism of carbohydrates.
⦁ It is one such messenger protein.
⦁ Haemoglobin is a protein and it is present in our bood.
⦁ Hemoglobin plays a crucial role in the transport of oxygen in our body.
⦁ Some proteins like keratin ad collagen are fibrous and tough.
⦁ They provide support to tendons and ligaments.
Vitamins and minerals
Functions of principal sources of vitamin and minerals
Vitamins and minerals are required in smaller quantities for maintaining health . They are called micronutrients.
⦁ Vitamins are essentially organic compounds.
⦁ There are several well-recognised vitamins.
⦁ Some of them like vitamin C and vitamin B are water-soluble.
⦁ Other vitamins A,D,K and E are fat-soluble.
⦁ Certain substances like beta-carotene and folic acid, which get converted into vitamins in our body called pro-vitamins.
Minerals in our diet
Our diet should essentially contain several minerals including calcium, iron, sodium, phosphorus, zinc and iodine. Each of these minerals plays various roles in the functioning of our body.
⦁ Calcium helps to build bones and teeth.
⦁ It helps in the proper functioning of muscles.
⦁ It helps in the functioning of heart and nerves .
⦁ It relieves pain and cramps.
⦁ It helps in clotting of blood.
⦁ Dairy products, soyabeans, rahi, sunflower seeds and legumes are rich in calcium.
Sodium: Sodium helps to control blood pressure.
⦁ It regulates the functioning of muscles and nerves.
⦁ Our food invariably contain the required amount of sodium.
Phosphorous: It is required for the formation of bones and teeth.
⦁ It is involved in metabolism of carbohydrates, fats and proteins.
⦁ Phosphorus is abundant in milk, milk products, whole grains, etc
Iodine: It helps in the secretion of thyroxine from thyroid gland.
⦁ It prevents goitre.
⦁ It helps to burn fat.
⦁ It converts beta-carotene into vitamin A.
⦁ It regulates energy production in our body.
⦁ It maintain hair, nails, skin and teeth.
⦁ Seafoods and vegetables are good source of iodine.
Zinc: Zinc in our diet helps to reduce cholesterol deposit.
⦁ It helps in making enzyme and insulin.
⦁ It supports metabolism of carbohydrates.
⦁ It facilitates the proper functioning of prostate gland.
⦁ Eggs, cheese, beef, pork, wheat germ, brewers yeast and pumpkin seeds are some of the good sources of zinc.
Potassium: It is a mineral that helps to regulate fluid balance in our body.
⦁ We also need it for the proper functioning of nerves and muscles.
⦁ Peanuts, bananas, green beans, mushrooms and oranges are a few good sources of potassium.