Classified of Nutrition
It is broadly classified into two main categories i.e. macronutrients and micronutrients.
The macronutrients are carbohydrates, fiber, fats, protein, and water. The macronutrients (excluding fiber and water) provide structural material (amino acids from which proteins are built, and lipids from which cell membranes and some signaling molecules are built) and energy. Some of the structural material can be used to generate energy internally, and in either case it is measured in Joules or kilocalories (often called “Calories” and written with a capital C to distinguish them from little ‘c’ calories). Carbohydrates and proteins provide 17 kJ approximately (4 kcal) of energy per gram, while fats provide 37 kJ (9 kcal) per gram, though the net energy from either depends on such factors as absorption and digestive effort, which vary substantially from instance to instance. Vitamins, minerals, fiber, and water do not provide energy, but are required for other reasons. Some are following :-
Proteins are complex organic molecules made up of carbon , hydrogen , oxygen and nitrogen. Most proteins also contain sulphur and phosphrous along with traces of other elements. They are not only essential for life but also play an important role in food preparation. The final quality of many food products is influenced by how the proteins are treated while food is being prepared. They are used to build , repair tissues and help to fight infection. A generous intake of high quality proteins is necessary for increase in muscles mass and skeletal development. A deficiency of calories and proteins can affect one’s optimum height increase and resistance to infections.
The Fats consumed in the diet need to be broken down into their constituent components namely glycerol and fatty acids before they can be utilized by the body. No chemical digestion of fat takes place in the mouth. Fat is broken into smaller particles by chewing and mixed with saliva. It give you energy and helps to absorb certain vitamins. Some foods naturally contain fats for example is dairy products , meats , seafood , seeds , nuts and coconuts. They are a concentrated source of energy in out diet. One gram of fat/oil gives 9 kcal when it is oxidized in the body. All tissues , except those of the central nervous system and brain can utilize fat as a source of energy. The kilocalories from fat spare dietary proteins from being oxidized for energy. An adequate intake of fat in the diet allows proteins to perform their main functions of growth and maintenance. It provides a protective padding to vial organs from mechanical shock and keeps them in place. It is necessary for the absorption of fat-soluble Vit. A, D, E and K.
Carbohydrates are present in various forms in the food we cook and processed food which we purchase and form the bulk of our diet. They are available in the market in the natural form , processed form or modified form as an additive in many different products. They are the body’s main source of energy. They provide calories and spare proteins from being oxidized for energy. Refined carbohydrates and poor dental hygiene are the reasons for dental caries in children. The consumption of fruits and vegetables, both cooked and uncooked , should be encouraged. Junk food and acrated beverages should be discouraged.
The micronutrients are Vitamin A,Vit. B1,Vit. B2,Vit. B12,Vit. C,Vit. D,Vit. E,Vit. K , Omega-3 fats,Omega-6 fatty acids and Cholesterol