Food is any material eaten to give nutrition to organisms. Generally, food is of animal, plant or fungi origin, and typically contains necessary nutrients, including proteins, carbohydrates, vitamins, minerals or fats. Food is the number one necessity, and without it we could not survive. We need protein in the form of protein-containing foods, which come from meats, poultry, fish, cheese and legumes, grains that are made into bread, cereals, pasta, potatoes and some fruits. Fruits and vegetables also have significant amounts of vitamin and mineral content.
The most important criterion in determining nourishment is how well an organism has been nourished in the past. If humans eat too many calories per day, it would defeat the purpose of eating, because we only live so long as the food we consume is good for us. It is interesting to note that human beings have consumed food from Stone Age to the present period with great success, and food can still be found in the sites that ancient people left behind.
In fact, food is a major factor in whether or not we feel good or bad. It is difficult to judge what is nourishment and what is junk, and most of the time a balanced diet is the key to healthy living. Food nutrition is an art as much as a science, because there are many factors that determine the healthfulness or otherwise of food. A balanced diet consists of at least a 3 food pyramid. These include a vegetable, a fruit and a dairy product.