Global warming reduces protein in key crops: study

Indian farmers plant paddy seedlings in a rice field on the outskirts of Amritsar
Indian farmers plant paddy seedlings in a rice field on the outskirts of Amritsar

Rising carbon dioxide levels from global warming will drastically reduce the amount of protein in staple crops like rice and wheat, leaving vulnerable populations at risk of growth stunting and early death, experts warned on Wednesday.

Researchers say they still don't understand how or why carbon dioxide emissions sap protein and other nutrients from plants, but the mystery is one that could have devastating consequences across the globe.

An additional 150 million people globally may be at risk of protein deficiency by 2050 because of rising levels of carbon dioxide in the atmosphere said the report in the journal Environmental Research Letters.

The study, led by Harvard University researchers, is the first to quantify the impacts of global warming on the protein levels of crops.

It relies on data from open field experiments in which plants were exposed to high concentrations of CO2.

Global dietary information from the United Nations was used to calculate the impact on people who live dangerously close to the edge when it comes to getting enough protein. Without it, growth is stunted, diseases are more common and early mortality is far more likely.

Carbon dioxide is a byproduct of fossil-fuel burning that helps trap heat around the Earth. Without stark action, these emissions are expected to climb in the decades to come, resulting in rising seas, hotter temperatures and more extreme weather events.

A leading hypothesis was that CO2 might increase the amount of starch in plants, thereby decreasing protein and other nutrients.

But lead author Samuel Myers, a senior research scientist in Harvard University's T. H. Chan School of Public Health, said that experiments did not back up the theory.

"The short answer is we really have no idea," he told AFP.

A leading hypothesis is that carbon dioxide might increase the amount of starch in plants (including wheat), thereby decreasing
A leading hypothesis is that carbon dioxide might increase the amount of starch in plants (including wheat), thereby decreasing protein and other nutrients

"We've looked into it pretty extensively."

Protein was not the only nutrient to take a major hit.

Other research has shown that rising CO2 will cut key minerals like iron and zinc in staple crops, leading to further nutritional deficiencies worldwide.

Africa, Asia hardest hit

Researchers calculated that by 2050, higher CO2 concentrations will sap the protein contents of barley by 14.6 percent, rice by 7.6 percent, wheat by 7.8 percent, and potatoes by 6.4 percent.

"If CO2 levels continue to rise as projected, the populations of 18 countries may lose more than 5 percent of their dietary protein by 2050 due to a decline in the nutritional value of rice, wheat, and other staple crops," said the report.

A full 76 percent of the people on Earth rely on plants for most of their daily protein, particularly in poor areas of the globe.

The hardest hit areas are expected to be Sub-Saharan Africa, where millions already don't get enough protein in their diets, and South Asia where rice and wheat are common staples.

India alone may lose 5.3 percent of protein from a standard diet, putting a predicted 53 million people at new risk of protein deficiency.

Researchers said solutions may include cutting carbon emissions, supporting more diverse diets, enriching the nutritional content of staple crops, and breeding crops that are less sensitive to the harmful effects of CO2.


Explore further

Rising carbon dioxide may compromise human nutrition, study says

More information: "Estimated Effects of Future Atmospheric CO2 Concentrations on Protein Intake and the Risk of Protein Deficiency by Country and Region," Danielle E. Medek, Joel Schwartz, and Samuel S. Myers, Environmental Health Perspectives, online August 2, 2017, DOI: 10.1289/EHP41

"Potential rise in iron deficiency due to future anthropogenic carbon dioxide emissions," M. R. Smith, C. D. Golden, and S. S. Myers, GeoHealth, Early View article, August 2, 2017, DOI: 10.1002/2016GH000018

© 2017 AFP

Citation: Global warming reduces protein in key crops: study (2017, August 2) retrieved 22 September 2019 from https://phys.org/news/2017-08-millions-protein-deficiency-result-human-caused.html
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Aug 02, 2017
Yet another gloom and doom study by those seeking to increase government funds toward their area of doctorate study. My ten year old granddaughter could teach them how to grow potatoes in a box or could teach them how to fish. More people in this world should leave the table hungry (specifically you fatties).
If humans need to adapt to rising co2 then we will.

Aug 02, 2017
The article is about the effect of CO2 on staple crops, however the Pys.org writer needs to insert the root of all evil:

"Carbon dioxide is a byproduct of fossil-fuel burning that helps trap heat around the Earth. Without stark action, these emissions are expected to climb in the decades to come, resulting in rising seas, hotter temperatures and more extreme weather events."

I hope they can figure this out and that GMO can help those effected.

Aug 03, 2017
Anything bad that has ever happened, or will happen, or is happening is attributed to global warming?

Aug 03, 2017
I'LL BELIEVE IT'S A CRISIS WHEN THE PEOPLE WHO KEEP TELLING ME IT'S A CRISIS START ACTING LIKE IT'S A CRISIS:
Al Gore's Home Devours 34 Times More Electricity Than Average U.S. Household. "Last September alone, Gore devoured 30,993 kWh of electricity. That's enough to power 34 average American homes for a month. Over the last 12 months, Gore used more electricity just heating his outdoor swimming pool than six typical homes use in a year."

I don't want to hear another goddamn thing about my carbon footprint" -- Glenn Harlon Reynolds

http://dailycalle...usehold/

Aug 07, 2017
The nimrod @shootist pulls a quote out of his ass and says 30,993 kWh. is 34 times the Average US House hold. I call BS! The US household is ~3000 Kwh. Your math doesn't jive. That is what happens when you listen to Fox all day, with Rush Limpalls on the radio when you don't have some rightwing horse turd blossom on the telly.

Aug 07, 2017
It's kind of a waste, actually. Most of these conspiracy bots couldn't even pass a Turing test.

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