The goal of the study was to increase the levels of zinc, iodine, iron, and selenium in rice grains to combat malnutrition. Researchers tested a method of spraying a mix of these micronutrients on rice plants in five countries. They found that the spray increased zinc, iodine, and selenium levels in the rice grains significantly. However, iron levels only increased at two sites. This method did not affect rice yield, showing promise as a sustainable solution to hidden hunger.