This images below are summary of the report “A study on the mineral depletion of the foods available to us as a nation over the period 1940 to 1991.” see the PDF is here. It shows the decrease of the mineral content of fruit and vegetables over a 31 year period.
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The reduction in mineral content undoubtedly continued after 1991 as intensive farming practices continue to dominate food production. The way crops are grown is linked to the state of soils, in particular the poor state of farmland due to the lack of organic matter. “Healthy soil is the foundation of the food system. It produces healthy crops that in turn nourish people.” From the FAO publication: The importance of soil organic matter
We are constantly urged to eat more fruit and vegetables yet they are becoming less nutritious. It is time to move away from high input agrochemical farming and grow more nutritious food that really does feed people in every way.
Successive governments have been locked into promoting a type of agriculture that does not work. It is time for change and the first steps should be to increase the amount of land available for allotments, community gardens and small scale commercial growing provided that they practice sustainable growing.