Food is any material consumed to provide nutrition to an organisms for life. Food is generally of animal, plant or fungi origin, and has necessary nutrients, including vitamins, proteins, carbohydrates, and fats. The human body requires approximately 4500 calories a day, of which about 3500 are completely required by the five major organs of the body – the brain, the heart, the lungs, the stomach, and the skin.
Among the major sources of food are the foods that we eat; food can be categorized into three main categories: vegetables (which include beans, peas, carrots, corn, sweet potatoes, squash), fruits (which include berries, citrus fruits, grapes, apples, melons, cantaloupe, honey, orange juice, and raw vegetables), grains (which include millet, wheat, cereals, corn, rice), and meat. Some of the most important sources of food are added sugars, such as those in chocolate and baked products, legumes (beans, peas, lentils, mushrooms, etc. ), and fats (present in butter, margarine, mayonnaise, etc. ).
In recent years, with the advent of processed food, junk food, and foods that are preserved with high temperatures and chemically agents, the nutrient value of food has declined significantly. This problem is particularly pronounced in developing countries where more families rely on packaged and processed foods for their daily meals. With less nutrient-rich food available to them at every meal, more people are resorting to more natural food alternatives, including fresh fruits and vegetables, home prepared diets, and even taking vitamin and mineral supplements. Although the overall quality of the food produced is not significantly affected, people generally report feeling less hungry and full after eating less food.