Study suggests significant decline in amounts of zinc, iron as CO2 becomes more abundant in the atmosphere
By Alan Mozes
The new analysis looks at how nutrients found in staple foods, such as wheat, rice, maize, sorghum, soybeans and field peas, hold up when exposed to the amount of carbon dioxide (CO2) that's expected to be in the atmosphere by the year 2050.
"The bottom-line is that our work shows that by 2050 a big chunk of the world's caloric intake will have lost a significant amount of nutrients like zinc and iron that are very important for human nutrition," said lead author Dr. Samuel Myers, a research scientist and instructor in medicine at the Harvard School of Public Health.
"Why this matters is because large vitamin and mineral deficiencies already exist today in about 2 billion people," Myers added. "And the burden of disease associated with these deficiencies is already enormous, particularly in developing countries.
"It's also the case that about 1.9 billion people now receive at least 70 percent of their dietary iron or zinc or both from staple crops like legumes and grains. So we have a major global health problem that's set to get much worse," he said.
Myers and colleagues reported their findings in a research letter published online May 7 in Nature.
Carbon dioxide is a gas that's naturally present in the atmosphere. But, it's also produced as a result of human activities, such as creating electricity and driving cars, according to the U.S. Environmental Protection Agency (EPA). The majority of CO2 now in the atmosphere comes from human activities, according to the EPA. CO2 is one of the heat-trapping gases that's contributing to climate change.
Currently, global carbon dioxide levels hover at around 400 parts per million. This compares with the roughly 280 parts per million level seen during the pre-industrial age, according to Myers.
"But most experts believe that the world will see 550 parts per million by 2050," he said.