GENERAL CONCEPTS IN NUTRITION
In the last decades, nutrition has been taking a predominant role in the scope of health, basic research and daily clinical practice. The crucial position nutrition holds in society makes it necessary to adopt a multidisciplinary approach consisting of an array of different social, economical and healthcare aspects.
Nutrition has been defined in many different ways and is understood to consist of a “series of complex phenomena whereby food is consumed, metabolised and used to carry out all body functions correctly and then eliminated or excreted by the body in the form of non reusable waste products". Diet and nutrition are two words used to define a scientific discipline that studies, analyses and puts into practice these processes by means of an adequate diet. The term “diet" means the amount and quality of foods that must be taken each day to meet the nutritional needs of our body.
The term “feeding" is understood to be the act whereby the body is “fed" the nutrients it needs. Feeding is thus a conscious voluntary and consequently “educable" action, as opposed to nutrition (involuntary, unconscious and non educable, as it depends on body processes such as digestion, absorption or transport of the nutrients contained in the foods to the target tissues).
These two definitions are important and it should not be forgotten that nourishing the body is more important than feeding it. We should always try to nourish ourselves correctly through the process of feeding. An individual´s state of health depends largely on the nutritional quality provided to tissue cells, in which the universal axiom “we are what we eat" becomes true. Because it is difficult to act upon involuntary nutritional processes, improving our nutritional quality has to be done through the quality of our feeding.
One of the characteristics of human beings is their omnivorous nature, that is, capable of benefitting nutrients from all sorts of sources thanks to the particularities of our digestive system. Moreover, daily life presents human beings with an array of opportunities that make it possible to receive a proper nutrition if such possibilities are known and correctly managed.