The alleviation of the world protein shortage.

It is difficult to anticipate the steps which will be taken during the next few decades to cope with the problem of providing adequate food for the ever-increasing world population. Curbs on population growth brought about by war and by contraception may play a part in eking out the world resources but the extent of this contribution is impossible to predict. In any event the nutritionist is not concerned with this aspect but only with ensuring that the best use is made of the available foodstuffs. Protein foods may be of plant or animal origin but, because animal protein originates through the coriversion of plants, plant protein must be considered to be of primary importance. Measures aimed at increasing the supply and utilization of plant protein will ultimately benefit the human population of the world whether or not animals are used to convert some of the plant protcin into meat, milk or egg protein. According to a recent United Yations publication (United Nations, 1968) 63 million tons of oilseeds are being at present employed either as crop fertilizers or animal feed. T h e conversion of plant protein into meat is inefficient, 4 tons of vegetable protein yielding approximately I ton of animal protein, and one can envisage the eventuality that even the efforts of modern husbandry research to improve animal productivity will not compensate for a wasteful use of plant protein resources. Mankind will then be compelled to forego the luxury of meat-eating. Before this stage is reached, however, governments must come to grips with the wastage of protein brought about by overproduction in certain protein-rich areas coupled with economic conditions which do not allow the transfer of this surplus protein to areas where it is badly needed. Kot only must waste be eliminated but maximum use must be made of the conventional sources of protein, and search must be continued for new sources. It is the purpose of this paper to mention some of the avenues which appear worthy of study, The primary protein sources available for feeding consist of seeds, leaves and tubers. Seeds in general contain relatively large amounts of protein and constitute the most important class of protein food for man and for non-ruminant livestock. Many, such as cereals, also contain considerable amounts of carbohydrate and can therefore contribute energy as well as protein to the diet. Tubers and leaves contain