CO2 output is damaging the nutritional value of staple crops like wheat.
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According to recent scientific research, rising carbon dioxide emissions are set to make the world’s largest staple food crops less nutritious. Field trials of wheat, rice, maize and soybeans showed that higher CO2 levels significantly reduced the levels of the essential nutrients iron and zinc, and also cut protein levels.

“We found rising levels of CO2 are affecting human nutrition by reducing levels of very important nutrients in very important food crops,” said Professor Samuel Myers, an environmental health expert at Harvard University and lead author of the study. “From a health viewpoint, iron and zinc are hugely important.”

Already around the world there are billions of malnourished people and this could worsen the already seriously endangered and declining health of these individuals. The study was conducted at seven sites in Japan, Australia and the United States. The scientists tested rice, wheat, maize, soybeans, field peas and sorghum over several growing seasons.

Although in the modernized world wheat, rice, maize and soybeans may seem relatively low in iron and zinc, in poorer or vegetarian societies where meat is rarely eaten, these foods are a major source of nutrients. About 2.4 billion people currently get at least 60 percent of their zinc and iron from these staples. In countries like Bangladesh, Iraq and Algeria, that percentage leaps up to over 75 percent. Carbon dioxide in the atmosphere is expected to reach 550 ppm in the next four to six decades.

When asked for solutions, Myers noted that iron and zinc fortification and supplementation programs have existed for years and not solved the problems. Alternatively, work is underway to develop biofortified crops and to develop new cultivars that are less sensitive to the elevated carbon dioxide levels, Myers said.