The word food brings to mind the act of eating food, but the idea goes much deeper than that. Food is any material consumed to give nutrition to organisms. Food is generally of animal, plant or fungi origin, and normally contains vital nutrients, including proteins, carbohydrates, vitamins, minerals or both, in the form of nutrients required by the organism to carry out its activities. It is the source of energy and nutrients and a reserve of last resort.
Plants are the primary food source of animals, while animal derives nourishment from plants. Animal food is further subdivided into flesh, milk and meat products. Fruits, vegetables, nuts and whole grains are the principal vegetable food sources. Milk is the most important animal food, containing essential fatty acids and other valuable nutrition. Protein, iron, sulphur, salt, calcium and other micronutrients are contained in meat.
It is interesting to note that the amount of carbohydrates that an individual consumes determines his level of energy and stature. On the other hand, it is observed that those who consume less carbohydrates are more active and have greater stamina. Generally speaking, carbohydrate-free diets can be very useful in athletes and weight lifters, since they require relatively lesser amounts of carbohydrates than normal individuals do. They have greater quantities of water and retain electrolytes better.
Virtually all animals and insects can be eaten as food. Herbivores eat plants, whereas omnivores eat animal or plant-based foods. A wide variety of foods are available as food for a carnivore or plant-eating herbivore. Carnivores or meat-eating creatures need protein sources, fat sources and carbohydrates. Herbivores and omnivores need similar but differing sources of fats, oils and vegetables.
Plants contain very few nutrients of which proteins, carbohydrates and vitamins are essential. This fact has been recognised since the beginning of agriculture. However, since the days of the caveman, people have enjoyed the benefits of plant-based foods such as fruits, vegetables, grains, seeds and nuts. Plants contain almost no fat but are high in carbohydrates and vitamins.
The best type of food is a healthy balanced diet containing all the necessary food groups. Some fruits and vegetables are easier to digest and absorb than others. Fruits have a low glycemic index compared to some other food types. Vegetables are rich in vitamins, fibre and minerals, but should be cooked before eating, as pesticides and chemicals can cause digestive problems. When followed in a proper manner, a balanced diet can provide a healthy and long life.