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56   A Tax on Nutrition
     The Washington Post, Saturday, August 5, 1967

     Amino acid deficiency is the greatest tax on the nutritional
well-being of the world's citizens.  In many diets, food crops furnish
insufficient quantities of lysine, threonine, tryptophan, and perhaps
methionine and some other amino acids.  Each is a specific molecule
with an individual function.  Each must be furnished in adequate
quantity.

     The people of wealthier countries obtain their quota of essential
amino acids from luxury foods like beef, fowl, fish or milk, the so-
called animal proteins, which are not available to impoverished 
populations.  Malnutrition is therefore an economic disease.

     Amino acid deficiency is also a genetic disease to which the 
entire human species (as far as we know) is vulnerable.  Biosynthetic
processes generally are under the control of genes: man's usual
capacity to make his own amino acid, tyrosine, can be impaired by a
mutation in the gene that codes for the essential enzyme,
phenylalanine hydroxylase.

     Some evolutionary ancestor of man and other mammals once had the
biochemical apparatus to make all the amino acids, but because there
was an abundance of them in the diet the genes irretrievably lost
their capacity for internal synthesis.  Green plants, yeasts and many
microbes still make their own.  When we obtain amino acids from our
diet we are in effect relying on the genes that have been preserved
in more autonomous species.

     The solutions proposed for this biochemical shortcoming must be
judged on economic grounds.  The culture and hunting of animals give
the most palatable answers, but on the whole these answers are too
costly to meet the world problem.  We can, however, stretch the
existing supplies many fold, one way is to process fish into a
protein-rich flour.

     Research toward more systematic, thoughtful answers should be a
fundamental part of our foreign policy, but the work that is going on
is a pitiable fraction of what is required to meet the urgent needs of
humanity.  We can, however, point to a scattering of exciting starting
points.

     Genetic modification of existing crop plants, and the
domestication of new ones, are among the most incisive innovations.
For example, in corn we have found mutant genes that greatly increase
the proportion of lysine in the meal.  To extend this observation,
we should have a deeper understanding of how this mutation works.
It appears to involve suppression of the synthesis of one seed protein,
zein.  This lets another nutritionally more favorable protein,
gliadin, take its place.

     Obviously, the more we learn about the control of protein
synthesis in plant cells, the better able we will be to produce crops
with the most desirable composition.  We have hardly begun to use the
many imaginative tricks that are possible in this game.

     Careful technical evaluation of existing resources can be the
most productive approach.  From this we learn that oilseed meals are
an especially useful source of effective proteins.  So far they have
been little exploited in human nutrition.

     Much research is still needed, however, to turn the new flours
made from soybeans, cottonseed and peanuts into a widely accepted
foodstuff.  Little has been done to improve the yield, composition
and palatability of oilseed crops or their adaptability to different
climates.

     Much of this work should be done in the developing countries
where the crops will have to be grown.  America should export the
means for finding out, rather than blindly transplant North American
agricultural science to other habitats.

     The production of "single-cell protein" by the fermentation of
petroleum wastes has attracted much attention.  The process is not
yet practical either in cost or in wide acceptability of the nutrient
product as food.

     It shows, however, that it is possible for an industrial process
to replace the universal genetic defect inherent in humans.

     More direct chemical methods for synthesis of amino acids are
already well known, and there is probably no limit to how cheaply
they can be made once the necessary development work is done.

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