(Inspired and developed from a programme broadcast on BBC Radio 4)
It is not uncommon to hear people of our parents’ generation say that the quality of food we eat has deteriorated. Our grandparents’ generation lived a long life and had a strong immune system because arguably they had an active life style. It could be true that their rice grain was heavier than ours.
Increasing use of chemical fertilizers to enhance crop productivity is perceived to have decreased the fertility of the soils world over. We are aware of NPK fertilizers, which have become indispensable these days. Occasionally, we have seen farmers adding elements such as boron (especially for fruit cultivation) if the soil is diagnosed to be deficient in that.
Elements such as boron, iron, and magnesium are essential for plant growth however are required in very low amounts. Hence, they are called the micro nutrients (minerals). To meet the ever increasing demand, we have generated many high yielding hybrid varieties of crop plants. Often, the yield is estimated as the number of grains per plant (more the better), area utilized to grow (lesser the better) and in some cases the sugar and protein content of the food grain. Indirectly, this is believed to have led to a “micro nutrient dilution” in the food we eat today. Researchers have reliably quantified the average decrease in mineral content in food grains (since early 20th century) to be around 20%, which is staggering.
The use of chemical fertilizers may have played a role however, the selection of hybrids is also proving to be equally critical. 100 years ago, 100 g of rice may have taken more land to cultivate and may have had less amount of carbohydrates. However, it was rich in all the minerals essential for a healthy human body.
More and more evidences in support of worsening food quality are accumulating everyday and they should make both scientists and farmers to re-think their current breeding and cultivation strategies.