J. F. BROCK 
to the ordinary man. This technological sophistication has 
entailed some potentially dangerous trends which will need to 
be carefully watched. These include certain vitamin 
deficiencies; caries of teeth and orthodontic problems; un- 
favourable morbidity and mortality experience from ischaemic 
heart disease, resulting from changes in quality and quantity 
of dietary fat; similar adverse trends in the incidence or 
prevalence of other diseases of multiple causation such as 
diabetes, peptic ulcer, appendicitis etc. ; and the possibility 
of chronic poisoning and even cancer from food additives 
and chemical residues in food. 
The claims of back-to-nature and other food faddists are 
found, when critically examined, to have few substantial bases. 
Finally, the non-physical advantages resulting from the 
increased productivity and leisure of urban development have 
been made possible by twentieth-century food technology, 
which is inevitably sophisticated in the sense defined. 
