COLIN CLARK 
protein, in the form of quantities of cereals required. One 
kilogram of wheat or similar grain, which in the hands even of 
the poorest cultivator must be milled down to goo grams, will 
then yield 3,150 calories. It follows that a community living 
entirely on grain, with a few wild plants or pills or other source 
to supply vitamins and minerals, will require, at the rates of 
daily requirements shown in the table, anything from 630 to 
750 grams per person per day, or 230-274 kilograms per person 
per year. These figures might be reduced by about 5 per cent 
for people consuming certain millets, which have higher calorie 
values than other grains. 
The protein content of grain is very variable, but it averages 
over eleven per cent. People consuming grain at this rate, 
therefore, would obtain sufficient protein. 
Studies by FAO (1960) show that even the poorest com- 
munities require about 1-5 kilograms per person per year of 
textile fibres!!, representing about 10 kilograms of grain, if we 
base our equivalent on the quantity of agricultural resources 
needed to produce it. Allowing for this, and also for the grain 
equivalent of small quantities of animal protein, green vege- 
tables, etc., required, we can estimate subsistence as 250-300 
kilograms of grain equivalent per person per year. We can 
define this as a “‘subsistence unit”’. 
It must be added that the diets to which we have become 
accustomed in North America, Western Europe and Australasia 
represent about ten times subsistence requirements. This does 
not, of course, mean that we eat more cereal; in fact we eat 
much less. The rest is made up of the meat, milk, eggs, bacon, 
fruit, etc., which have required large quantities of cereals to be 
fed to livestock in order that they might be produced, or have 
used up the grain equivalent of substantial quantities of agri- 
cultural land and labour. Many doctors tell us that we would 
be healthier if we ate less. 
We will consider the agricultural resources, both labour and 
land, required to produce one unit of subsistence, that is to say, 
the amount of agricultural production which would provide a 
necessary minimum of food and clothing for one person for a 
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