Rapid Maturation and Ageing 11)7 



and increased the duration of life from nineteen days up to 

 twenty-nine days; Kopec (1928) reached similar conclusions 

 with Drosophila, caterpillars and tadpoles, and others using 

 protozoa (Rudzinska, 1952), Cladocera (Ingle, 1933), mice 

 (Tannenbaum, 1947) and rats (Riesen, Herbst, Walliker and 

 Elvehjem, 1947; Templeton and Ershoff, 1949; Sherman, 

 Campbell and Ragan, 1949). Carlson and Hoelzel (1946) 

 found that alternate fasting and feeding increased the life- 

 span of rats without influencing the growth rate. The most 

 extensive and important experiments are of course those of 

 McCay upon trout and rats (McCay, Dilley and Crowell, 1929; 

 McCay, Sperling and Barnes, 1943; McCay, 1952). There 

 can be no doubt that in general underfeeding of lower animals 

 during the growing period delays maturation and increases 

 the life-span. 



If this is true of most lower animals it may be true of man 

 in whom indeed there is evidence that overfeeding hastens 

 puberty (Bruch, 1941; Le Marquand, 1951). Further, as 

 Brody (1945) showed, man differs from other animals in 

 spending a relatively long time in reaching maturity which in 

 this context means ability to reproduce. In shortening this 

 period by overfeeding we may well be harming children and 

 shortening their life span. McCance (1953) from Cambridge, 

 England, has supported this possible damage to children by 

 overfeeding: "we may be shortening the lives of the generation 

 now growing up in this country by trying to make them grow 

 faster with school meals and school milk". I concluded much 

 the same in a Cutter Lecture I gave in Cambridge, Mass., a 

 couple of years earlier (Sinclair, 1951): 'T think we should 

 bear in mind that the optimum rate of growth of children is 

 not necessarily the maximum, and that harm may be done bv 

 excessive feeding of children with milk or school meals and 

 now by medication with vitamin Bjg and aureomycin, even 

 though these activities make them grow more quickly and 

 mature earlier". Of course it may be maititaiiicd that tlie 

 children are deficient in vitamin B^g if they grow faster when 

 this vitamin is administered although presumably the same 



