components of food
The components of food are certain organic substances and minerals found in food. They are called nutrients. Nutrients provide the body with energy and enable it to grow, repair and maintain itself. Hence it is important that we understand the exact role of nutrients in our food and recognize the various foods that provide these nutrients. There are almost 40 essential nutrients of which carbohydrates, proteins, fats, vitamins, minerals, roughage and water are the most important. The food that we eat contains five main components: Carbohydrates: Carbohydrates provide energy to the body.
Bread , rice, fruits and fruit Juices, honey and corns are some sources of carbohydrates. Fats: Like carbohydrates, fats too provide energy to the body. The excess carbohydrates are converted into fats and stored in the body. Meat, vegetable oil, milk, butter, cheese, ghee, cream and dry fruits are some sources of fats. Proteins: Proteins are essential for growth. Our body needs proteins for muscle-building and for repairing worn-out tissues. Chicken, fish, eggs, milk, cheese, pulses and soyabeans are some sources of proteins.
Vitamins: Vitamiins are needed for the normal functioning of our body. There are 13 vitamins needed by our body, which come from different sources. Fruits, green leafy vegetables and fish are some sources of vitamins. Minerals: Just like vitamins, minerals help in keeping our body heathy. They perform functions in the body such as strengthening the bones and maintaining a normal heartbeat. Milk, meat, fish, eggs, vegetables , fruits and pulses are some sources of minerals. Foods can be grouped on the basis of the nutrients contained in them and their functions in the body.
Based on their functions they can be divided into three groups ??Energy giving foods ???Body building foods ???Protective foods Energy giving food Energy is required by the body to do work and to perform all the physiological functions of the body. Carbohydrates like rice wheat, potato and fats like ghee and oil belong to this group. Body building food Our body needs to grow. Due to constant wear and tear in the body, new cells have to be built to repair the damaged parts. Proteins like milk, eggs, meat, cheese and dal help in body building. Protective foods Vitamins and minerals belong to this group.
Absence of these constituents cause eficiency diseases like rickets, beriberi etc. Vegetables and fruit are rich in vitamins and minerals. The table below shows the three food groups and their sources Food group according to function Major nutrient Food containing the nutrient Energy giving carbohydrate and Fat Body building Protein Milk , Meat-Mutton, chiken, fish, Egg white, Pulses, like dalsgram,soya bean peas Protective Minerals, Vitamins Vegetables specially green leafy vegetables like spinach, cabbage and Dietry fibre such as brinjal, beans and fruits Some Facts Facts about calories:
You need enough calories to maintain your energy level, but no more than you can burn off. This is called an energy balance. ??? If you take in more calories than you burn, you gain weight. ???If you take in fewer calories than you burn, you lose weight. ??? If you balance the two, you maintain your weight. ??? Even when you are dieting, however, calories should not be cut back so much that your energy needs are not met. The number of calories you need depends primarily on age, gender, and activity level. Facts about dietary cholesterol: Remember: “cholesterol-free” does not mean “fat-free.
Dietary cholesterol is a fat-like substance found in all foods of animal origin: egg yolks, meat, poultry, fish, milk, and milk products. ??? Because our bodies make cholesterol, it is not required in our diets. However, because most people eat foods that contain cholesterol, it is important to avoid excessive amounts. The amount of cholesterol you consume can affect your blood cholesterol levels. Types of fats: Fatty acids are the basic chemical units in fat. They may be saturated, polyunsaturated, monounsaturated, or trans fats.
These fatty acids differ in their hemical compositions and structures, and in the way in which they affect your blood cholesterol levels, according to the following: ??? Saturated fat: o is used by the liver to manufacture cholesterol. o has been shown to raise blood cholesterol levels, particularly the LDL or “bad” cholesterol level which can increase your risk of heart attack and stroke. o should comprise no more than 10 percent of your daily calorie intake. o saturated fat can be found in: meats, butter, cocoa butter, coconut, and palm oils. ??? Polyunsaturated fats: o do not appear to raise blood cholesterol levels. xamples include: safflower, sunflower, corn, and vegetable oils, and soybean oils. Monounsaturated fats: o do not seem to increase bad cholesterol levels and may help boost HDL or “good” cholesterol in the blood. Increased HDL levels have been linked to a lower risk of heart disease. o examples include olive and canola oils. Trans fats: by-products of hydrogenation, a chemical process used to change liquid unsaturated fat to a more solid fat. Structurally similar to saturated fat, trans fatty acids may have a great impact on raising total and LDL cholesterol levels.
Trans ats should be avoided as much as possible. o examples include stick margarine and should be no more than 30 percent of your daily calorie intake. Facts about fats: All fats contain about the same number of calories – teaspoon for teaspoon. There is no low-fat fat. ??? Fat is the most concentrated source of calories, supplying more than twice as many calories per gram as either carbohydrates or proteins. ??? Most people tend to get far too much fat in their diet, which contributes to health problems such as obesity, high blood cholesterol, and heart disease.
While coconut nd palm oils contain no cholesterol, they are high in saturated fat and should be avoided. Facts about fiber: Fiber is the indigestible portion of food. There are two types of fiber: soluble and insoluble. o Soluble fiber – found in such foods as oat bran and dried beans, can lower blood cholesterol in some people. o Insoluble fiber – found in foods such as wheat bran and is known to have many health benefits. While this type of fiber has not been found to lower cholesterol, it is useful in weight control because it creates a feeling of fullness. Facts about sodium:
Although salt is the major contributor of sodium in our diets, sodium and salt are not the same, contrary to popular belief. A teaspoon of table salt contains 2,300 milligrams of sodium. ??? Sodium is a mineral needed to maintain body fluids and proper nerve function. It occurs naturally in some foods, but most of the sodium in our diets comes from seasonings and ingredients we add to foods. ??? Although sodium is essential, most of us consume more than we need. In some people, too much sodium in the diet can cause the blood pressure to rise, putting them at risk for heart disease and stroke.