190 R. A. McCance and E. M. Widdowson 



development may be limited and fast orowth essential for 

 survival. Some of the mi<^Tant l)irds illustrate this very 

 elearly but a little pig like ours Avould almost certainly fall 

 by the wayside in its natural surroundings long before it had 

 reached maturity even if it has three or even ten times the 

 normal expectation of a pig's life in our little sty. Methuselah, 

 you will recollect, died at the age of nine hundred and sixty- 

 nine years. We do not know the age at which he married 

 but he appears to have been one hundred and eighty-seven 

 when his first child was born. Unless the writer of the book 

 of Genesis forgot to put in the decimal points one may surmise 

 that Methuselah must have had a very sheltered upbringing 

 and not quite enough to eat for his first hundred years or so. 

 Unlimited food of the right kind leads to rapid development, as 

 you can see from the growth curve of our big pig who was only 

 just over seven months old, yet she weighed 350 lbs. and had 

 ovulated three times by this age. Rapid growth and develop- 

 ment must be an advantage in the world at large but once 

 the vulnerable early stages of an animal's life have passed, 

 too much food of any kind is probably a serious handicap to 

 survival in natural surroundings, and we know that it is a 

 modest one for a man even in the cloistered world of modern 

 civilisation. We clearly want to provide for rapid development 

 in early life, followed by a prolonged period of productive 

 adult life, yet the duration of life as a whole appears to be 

 closely related to the rate at which an animal approaches its 

 mature weight (Brody, 1945). How to break this natural 

 law appears to be one of the little problems waiting to be 

 solved. 



These ideas have a bearing on pathology much wider than 

 might at first be supposed. If the principle be accepted that 

 the capacity of a cell to reproduce itself is reduced and that 

 its demise is hastened by the accumulation of food materials 

 or calorific reserves within it, certain diseases become more 

 understandable. Take kwashiorkor, for example. This is now 

 thought to be a state of extreme undernutrition in a weanling 

 child due to a deficiency of protein, an essential requirement 



