Increasing Carbon Dioxide lowers nutrient content of many plants. Plants require proteins in order to grow, in the course of sucking up those, greens also take in nutritious minerals like zinc and iron.
Agronomists have recorded a steady decline in some of those minerals, proteins and vitamins for half a century. USDA data shows that kale from 1999 had 23 percent less iron than 1950s greens did. But now the blame is shifting to include CO2 from industrialization.
In 2002, mathematician Irakli Loladze theorized that photosynthesis requires fewer proteins as CO2 climbs, which means plants acquire fewer incidental micronutrients while sucking them up. He recorded an 8 percent nutrient drop, on average, in certain kinds of crops, including rice and wheat.
The two studies drew upon more than a decade of data from agronomists, who had planted 41 varieties of six food crops include wheat, maize, sorghum, field peas, soybeans, and rice and surrounded part of each field with nozzles blasting enough CO2 to warm any greenhouse.
Analysis of the harvests showed maize and sorghum fared fine, but rice lost about 3 percent of its zinc. It could put hundreds of thousands of people at risk of deficiency, leaving them more vulnerable to respiratory diseases, diarrhea, and malaria.
Researchers estimate that mostly pregnant women and children living in poverty could end up short on essentials such as iron, protein, and zinc. Plus, there’s a chance these extra-sugary plants will contribute to an increase in diabetes.