Food is any material consumed to supply nutrition to the organisms. Food consists of any organic material from plants, animals or fungi, and includes required nutrients, including vitamins, proteins, carbohydrates, and minerals. It is the main energy supply and most of the living organisms depend on food. A wide range of different kinds of food are available in the markets. These include milk, meat, fish, vegetables, fruits, cereals, legumes and pulses.
Most of the food is categorized according to nutrient content, which is the proportion of one or more essential nutrients in comparison with the total calories of that food group. Commonly, the classification of food is into three main groups: foods containing carbohydrates, proteins or fats, foods containing a fiber content, and foods containing a small amount of both carbohydrate and protein. Foods that fall in one of these categories are termed as low-fat foods, low-carbohydrate foods and high-fiber foods. The food groups can be further classified into “food groups” based on the types of carbohydrates they contain, which is further subdivided into “sugar,” “sugar sweetened” and “sugar-free.” Generally, carbohydrate-rich foods are rich in protein and good for the human body, whereas carbohydrate-free food is devoid of protein but have a high level of calories. Foods that fall in a large number of categories under the “sugar” heading are called “refined sugars,” while foods with a high level of fiber content are called” soluble fibers.”
Fats, oils, nuts and fruits constitute the “oils” category. Fats are mainly obtained from animal products (beef, pork, lamb), nuts (oil from cashews, walnuts, almonds), fruits (apples, cherries, mangoes, oranges), and vegetables (peas, beans). Fats are used in place of other sources of nutrients in order to preserve the texture of food. Fats also add flavor to food and thus they are consumed even in place of sugar or salt. Vegetables are low in calories but provide an excellent source of nutrition and are also easily digested by the body.