Increasing levels of dioxide reduce the nutritional value of rice

Increasing concentrations of carbon dioxide in the atmosphere due to climate change gradually reduce the nutritional value of rice, a basic feed for more than two billion people, especially in the poorest countries, thus threatening their health, according to a new international scientific research.

The study shows for the first time that rice grown under conditions of increased atmospheric dioxide has reduced four important vitamins B (B1, B2, B5, B9), less protein and also fewer other nutrients such as iron and zinc.

Researchers from the United States, Japan, Australia and China, who carried out research with 18 common varieties of rice, made the relevant publication in the journal Science Advances. Experimental rice crops were made with artificially elevated levels of dioxide (568 to 590 ppm), as expected in the second half of our century.

It was found that when there is increased airborne dioxide, mean levels of vitamin B1 (thiamine) in rice are reduced by 17%, 1, B2 (riboflavin) by 16.6%, B5 (pantothenic acid) by 12.7% and B9 (folate) by 30.3%. Climate change does not change levels of vitamin B6 (pyridoxine) and calcium while increasing levels of vitamin E.

Also, increased dioxide reduces by about 10% the level of protein, 8% of iron and 5% of zinc, containing the rice.

“Rice has been the basis of nutrition for many populations in Asia for thousands of years and is the fastest growing food in Africa. Reducing nutritional quality of rice will affect maternal and child health for millions of people, “said researcher Christy Ebi, a professor at the University of Washington.

Approximately 600 million people, mostly in Southeast Asia (Bangladesh, Cambodia, Indonesia, Myanmar, Vietnam, etc.), take over half of their daily calories and protein from rice, the physiology of which is affected by climate change. The research has shown, however, that not all rice varieties respond to the increased dioxide, and therefore – through further research – those that can better preserve their nutritional value.