Rising CO2 levels will make crops less nutritious

Higher levels of carbon dioxide are known to contribute to global climate change and scientists often discuss how crop production may be affected by it. New research is now going a step beyond and looking at the effect of carbon dioxide on the nutritional value of food crops. The findings show that at the current rate of growth of CO2 emissions, hundreds of millions of people will be at risk of significant nutritional deficiencies by 2050.

The new study, led by the Harvard TH Chan School of Public Health, builds on previous research that linked rising CO2 to protein, iron and zinc deficiencies and focused on crops such as rice and wheat. Global hunger rates are alarmingly high and over two billion people are estimated to already have some type and level of nutritional deficiency.

The study shows that higher levels of carbon dioxide will result in a 3-17% reduction of said nutrients and could result in 175 and 122 million people becoming zinc and protein deficient respectively. “This is another demonstration of how higher CO₂ could affect global health that may not be as well recognised,” Dr Matthew Smith, co-author of the study, told the Guardian. “Continuing to keep up our vigilance around reducing CO₂ emissions becomes all the more important because of this research.”

Climate change is expected to exacerbate issues such as famine and hunger in some regions, while growing seasons may be extended in other parts of the world. It is often cited that those communities that will experience these negative effects of climate change the worst are in poorer countries.

So is the case of lower nutritional values, as North Africa, South and Southeast Asia and the Middle East are expected to see the biggest drop in nutrition in crops. The Americas, much of Europe and Australia will see little effect on nutritional levels due to higher CO2 emissions.