One of the great discoveries in Nutrition was that of Justus von Liebig in the 19th century. He showed that crop production is limited by the nutrient in shortest supply. His law of the minimum.
Plants require carbon, hydrogen and oxygen from atmospheric gases and water. And of course trace elements.
The work of Liebig has transformed agriculture and taken some of the worry of Malthus and his theory of population from us, at least for a while.
The ready provision of food has enabled the human population to grow in an unfettered manner. However the excess of nitrates and phosphorous added to the land and the seepage into the overall system especially water has had dire consequences. Including a proliferation of algal bloom. This has had consequences for fish stock and available oxygen in the water.
Elser and colleagues in Ecology Letters have made a meta analysis of the effects of these two elements on the biomass. The effect of adding nitrogen and phosphorous to growing plants is profound. At the same time there is a synergistic effect and both are required. The effect is to alter complex metabolic relationships within the plant which have yet to be fully understood
Nevertheless we have here an important nutritional point of relevance to human nutrition. There are limiting elements in our diet.
The concept of a balanced diet is not a platitude but central to good nutrition.
Davidson and Howarth 2007 Nutrients in synergy Nature vol 449, 1000-1001
- Martin Eastwood