"What then is that precious something contained in our food which keeps usfrom death? That is easily answered. Every process, event, happening -- callit what you will; in a word, everything that is going on in Nature means anincrease of the entropy of the part of the world where it is going on. Thusa living organism continually increases its entropy -- or, as you may say,produces positive entropy -- and thus tends to approach the dangerous stateof maximum entropy, which is death. It can only keep aloof from it, i.e.alive, by continually drawing from its environment negative entropy -- whichis something very positive as we shall immediately see. What an organismfeeds upon is negative entropy. Or, to put it less paradoxically, theessential thing in metabolism is that the organism succeeds in freeingitself from all the entropy it cannot help producing while alive."

WHAT IS LIFE? by Erwin Shrödinger
First published in 1944.
http://www.dieoff.com/page150.htm