More CO2 also means less nutritious food

Jun 06, 2014

Rice, maize, soybeans and wheat are the main source of nutrients for over 2 billion people living in poor countries. But with climate change and the rising amount of CO2 in the air we breathe, their already low nutrient value compared to meat, for instance, is set to decrease.

According to a study published this week in Nature, are slowly making the world's staple food crops less nutritious. Wheat, maize, soybeans and rice will see their levels of and zinc, as well as proteins, go down between now and 2050.

'We found that rising levels of CO2 are affecting human nutrition by reducing levels of very important nutrients in very important ," said Prof Samuel Myers from Harvard University, United States, and lead author of the study. "From a health viewpoint, iron and zinc are hugely important.' Close to one third of the world's population already suffers from iron and zinc deficiencies, and according to this new study the rising levels of CO2 would only make things worse.

To obtain these results, the team compared in field crops grown in ambient CO2 levels, about 380-390 parts per milliion (ppm) at the time of the work, with those grown in the elevated CO2 levels expected by 2050. In order to take account of variable growing conditions, the researchers analysed 41 different strains grown in seven locations on three different continents.

Due to an unknown biological mechanism, wheat grown in high CO2 levels had 9% less zinc and 5% less iron, as well as 6% less protein, while rice had 3% less zinc, 5% less iron and 8% less protein. Maize and soybeans saw similar falls but, the latter being a legume it did not see lower protein.

The impact on human health resulting from the drop in the level of is less clear than for the zinc and iron loss. Myers said this could eventually increase the rate of metabolic syndrome, diabetes, heart disease and stroke.

Could concerned populations just eat more staple foods to meet zinc and iron requirements? Not according to Myers, who points at the need for food production to already double by 2050 in order to meet the demand of rising populations. And while some of the varieties used in the research performed better than others, breeding programmes focused on these traits 'will not be a panacea for many reasons including the affordability of improved seeds and the numerous criteria used by farmers in making planting decisions that include taste, tradition, marketability, growing requirements and yield,' he said.

Some have already mentioned how the study contradicts previous findings that increased CO2 levels can improve crop yields on some circumstances, to which Myers answered: 'There may be a little positive effect, but the people who work in this area would not want to hang their hat on that in the face of the many other negative effects of , including heatwaves, droughts and floods.'

Explore further: Rising carbon dioxide may compromise human nutrition, study says

More information: "Increasing CO2 threatens human nutrition." Samuel S. Myers, et al. Nature 510, 139–142 (05 June 2014) DOI: 10.1038/nature13179. Received 25 November 2013 Accepted 24 February 2014 Published online 07 May 2014

add to favorites email to friend print save as pdf

Related Stories

Findings may advance iron-rich, cadmium-free crops

May 29, 2014

With news reports of toxic cadmium-tainted rice in China, a new study describes a protein that transports metals in Arabidopsis plants and holds promise for developing iron-rich but cadmium-free crops.

Recommended for you

Obama readies climate change push at UN summit

2 hours ago

President Barack Obama will seek to galvanize international support in the fight against climate change on Tuesday when he addresses the United Nations, with time running out on his hopes of leaving a lasting ...

New toxic spill traced to Mexico mine

2 hours ago

Civil protection authorities have confirmed new toxic spills in northwestern Mexico, where a massive acid spill from a copper mine contaminated waterways.

World greenhouse emissions threaten warming goal

17 hours ago

Emissions of greenhouse gases are rising so fast that within one generation the world will have used up its margin of safety for limiting global warming to 2°C (3.6°F), an international team of scientists ...

Tens of thousands join London climate march

17 hours ago

Tens of thousands of people in London joined a global day of protest Sunday to demand action on climate change, among them British actress Emma Thompson who said the challenge to save the planet was like ...

User comments : 15

Adjust slider to filter visible comments by rank

Display comments: newest first

antigoracle
1.9 / 5 (9) Jun 06, 2014
Due to an unknown biological mechanism

So, let's blame CO2. That's what the AGW Cult calls science.
Now where's my millions in funding.
Maggnus
4 / 5 (8) Jun 06, 2014
ya that's some plant food!

Then there's the psycho loony-tunes brigade. Guess in somebody's cartoon world the truth of things like science are negotiable.
rockwolf1000
3.5 / 5 (8) Jun 06, 2014
Due to an unknown biological mechanism

So, let's blame CO2. That's what the AGW Cult calls science.
Now where's my millions in funding.


The biological mechanism is unknown.

The root cause IS known.

If you weren't so blatantly stupid you would realize they have set up an outdoor lab in a field, added extra CO2, then analyzed the results. They are scientists, and unlike you they look for facts instead of just spewing an never ending supply of garbage out of their mouths all day.

My goodness you are dumb.
Bob Osaka
2.3 / 5 (3) Jun 06, 2014
"41 different strains, seven locations on three continents," one wonders how many of these were GMO's. Genetically modifying organisms to retain more iron and zinc while increasing protein content is well within the realm of possibility given the time frame. There are political and possibly unforeseen medical consequences to using GMO's but these are problems for bioengineers and their agribusiness corporations.
Shootist
1.5 / 5 (8) Jun 06, 2014
"Generally speaking, I'm much more of a conformist, but it happens I have strong views about climate because I think the majority is badly wrong, and you have to make sure if the majority is saying something that they're not talking nonsense." - Freeman Dyson
Maggnus
4 / 5 (8) Jun 07, 2014
"Generally speaking, I'm much more of a conformist, but it happens I have strong views about climate because I think the majority is badly wrong, and you have to make sure if the majority is saying something that they're not talking nonsense." - Freeman Dyson
Hey troll, here's what Freeman also said: " No doubt that warming is happening. I don't think it is correct to say "global," but certainly warming is happening. I have been to Greenland a year ago and saw it for myself. And that's where the warming is most extreme. And it's spectacular, no doubt about it. And glaciers are shrinking and so on."

So why don't you mention that part SHootist? Why be such a creep?
fasturtle
3.7 / 5 (3) Jun 07, 2014
rockwolf1000, they got it all wrong here about reasons. it's not just zinc or iron. much more.
the biggest one: http://x.co/4nYoU

antigoracle
1.6 / 5 (7) Jun 07, 2014
Rice is a primary source of carbohydrates, and of course they discredit the significant increase in that due to increased CO2. Unless the AGW Cult believe carbs is not nutrition.
Wolfie, you should try independent thought sometimes.
thermodynamics
4.3 / 5 (6) Jun 07, 2014
Rice is a primary source of carbohydrates, and of course they discredit the significant increase in that due to increased CO2. Unless the AGW Cult believe carbs is not nutrition.
Wolfie, you should try independent thought sometimes.


AG: Wolf quoted from this article to make his point. Since you are not quoting from the article, you need to point out an article or source (other than Rush) which shows you are not just spouting garbage (as you usually do). For instance, under what conditions does rice become more productive? What happens to rice in south-east Asia if climate change stops the monsoons for a few years? You are a one-dimensional thinker and that one dimension is linked to Fox News.
antigoracle
1.6 / 5 (7) Jun 07, 2014
Some have already mentioned how the study contradicts previous findings that increased CO2 levels can improve crop yields ....

Hey thermomoron, try reading sometime.
thermodynamics
4.3 / 5 (6) Jun 07, 2014
AG: I did read. I read this part:
'There may be a little positive effect, but the people who work in this area would not want to hang their hat on that in the face of the many other negative effects of climate change, including heatwaves, droughts and floods.


That is why I say that you are a one-dimensional thinker. You can't see the bigger picture which includes the other effects. Please supply the links that show that the result is going to be positive for food supplies for the globe? Or, do you just think about your back yard? Or, is it your mother's basement?
antigoracle
1.6 / 5 (7) Jun 07, 2014
Hey thermomoron you obviously don't think, but then with your head up Al Gore, where the sun don't shine, I can't blame you.

http://journals.c...=4801124
Vietvet
4.3 / 5 (6) Jun 07, 2014
Hey thermomoron you obviously don't think, but then with your head up Al Gore, where the sun don't shine, I can't blame you.

http://journals.c...=4801124


Your link from a 1990 paper says nothing about nutrient value.
thermodynamics
4.3 / 5 (6) Jun 07, 2014
Hey thermomoron you obviously don't think, but then with your head up Al Gore, where the sun don't shine, I can't blame you.


Why is it you keep referring to Gore. I have never used him as a reference. You seem to mention him every time you post. Do you have a thing for him? You do know that you can marry him in 11 states now if you really want to. Just man up and ask him. That would get you out of your mom's basement.
antigoracle
1.6 / 5 (7) Jun 08, 2014
Hey thermomoron is carbohydrates not a nutrient?
Experimental evidence show increased CO2, increasing rice yield from 20 to 30 percent.

(So you recommend Gore eh. With your head up his colon, does that mean you come with him?)