New Delhi: For the first time, an Indian Council of Agricultural Research-led study examines the food value of high-yield varieties of wheat and rice and delivers some dire warnings as the foodgrains that we eat have lost food value, instead, they are accumulating toxins, reports Down To Earth’s latest cover story.

“For the past 50 years, India has been introducing high-yielding rice and wheat varieties at breakneck speed to achieve food security. The ICAR-led study has examined the food value of these modern grains and reports that breeding programmes focused on developing high-yielding varieties have altered the nutrient profiles of rice and wheat -- to the extent that their dietary and nutritional value has gone down,” says the report.

The study has gone ahead to assess the health impact of this “historical shift” in nutrient profiles of rice and wheat and warns that the impoverished staple grains could worsen the country’s growing burden of Non-Communicable Diseases.

Down To Earth and the Centre for Science and Environment organised a webinar recently to discuss the coverage of the new study. Panellists included Sovan Debnath, Soil Scientist, ICAR-Central Agroforestry Research Institute of Jhansi and the lead author of the study; Biswapati Mandal, former Professor, Directorate of Research, Bidhan Chandra Krishi Viswavidyalaya of Kalyani and the study’s co-author; Ishi Khosla, Clinical Nutritionist, Consultant and Writer, and Shagun, Journalist.

When the Green Revolution began in India, the aim was to feed the rapidly growing population and to become self-sufficient in food production. Hence, the main motive of agricultural scientists was to improve yield.

“After the 1980s, the focus of breeders shifted to developing varieties that were resistant to pests and diseases and tolerant to stresses such as salinity, moisture and drought. They did not have the luxury of thinking whether the plants were taking in nutrients from the soil or not. Hence, over some time, what we are seeing is that plants have lost their capacity to take up nutrients from the soil,” said Dr Mandal.

The study is an extension of another study that scientists from ICAR and Bidhan Chandra Krishi Viswavidyalaya conducted in 2021. The study explored the reasons for zinc and iron deficiency in populations dependent on a cereal diet -- high-yielding cultivars of rice and wheat, when tested, revealed a downward trend in grain density of zinc and iron.

“Our experiments showed that modern-bred cultivars of rice and wheat are less efficient in sequestering nutrients like zinc and iron, despite their availability in soil,” says Debnath, who was one of the scientists behind the 2021 study as well.

The 2021 study also showed that the increase in the proportion of the global population suffering from zinc and iron deficiency over the last four decades coincided with the global expansion of high-yielding, input-responsive cereal cultivars released in the post-Green Revolution era. The concentration of essential nutrients like zinc and iron has decreased by 33 per cent and 27 per cent in rice, and by 30 per cent and 19 per cent in wheat, respectively.

What’s worse, the concentration of arsenic, a toxic element, in rice has increased by 1,493 per cent. “In other words, our staple foodgrains are not only less nutritious but also harmful to health. Amid continuous genetic tampering under the modern breeding programme, the plants have also lost their natural evolutionary defence mechanisms against toxins,” says the report.

The depleted concentration of essential nutrients in staple grains could result in a higher prevalence of diseases related to neurological, reproductive and musculoskeletal systems.

Significant efforts are being made in the country to improve the nutritional profile of food grains. Agricultural scientists have turned to landraces and wild species of cultivated varieties for answers. Under a special project on bio-fortification, launched by the Union government, scientists at ICAR and other agriculture universities have undertaken germplasm exploration to find donor varieties that are high in nutritional content. So far, institutes under ICAR have developed 142 bio-fortified varieties. “However,” says Shagun, “these varieties are far from being popularised and adopted by farmers on a large scale.”