Climate Change Could Affect Our Nutrition Due to Carbon Dioxide Concentrations

A new study published on Wednesday examined how increasing carbon dioxide levels could endanger human nutrition in the future, including dietary deficiencies of zinc and iron which claim 63 million lives each year.

Crops are threatened by the growing presence of CO2, and scientists predict that not only can climate change decrease crop output, but it can also alter their nutritional value. The Harvard School of Public Health study, "Increasing CO2 Threatens Human Nutrition," was published in the journal Nature.

The researchers found that C3 grains and legumes - the primary dietary source of zinc and iron for humans - will have lower concentrations of these nutrients when grown under field conditions that have elevated atmospheric carbon dioxide concentration, which is projected to occur around 2050. As a result, carbon dioxide could potentially affect global health within the next 30-plus years.

"The public health implications of global climate change are difficult to predict, and we expect many surprises," the researchers articulated via this NBC News article. "The finding that raising atmospheric carbon dioxide lowers the nutritional value of (certain) food crops is one such surprise that we can now better predict and prepare for."

According to the United Nations, between 2 billion and 3 billion people rely on the crops in danger for zinc and iron. These nutrients are important for sustaining a healthy immune system, which is important since the World Health Organization recently reported that many bacteria are becoming resistant to their treatments.

This is the largest study to date that examined the subject. The researchers also found that protein in wheat, rice, and peas will decline in the second half of this century. The study arrived at these results after recording data from six growth years on field sites in Japan Australia, and the United States.

The bottom line: crops are losing nutrients as atmospheric levels of CO2 increase. However, the United States and China - two of the world's largest emitters of greenhouse gases - amended their environmental laws to reduce their emissions to help improve air quality. These new regulations could have a beneficial effect on the negative results unearthed in the Harvard study.