Why Grain Is Getting Less Nutritious
When you think of climate change, you probably think of rising temperatures and sea levels, not nutrition. However, as NPR reports, the increase in carbon dioxide brought on by climate change will most likely have a significant impact on the world’s food supply. Not all of the effects will be bad, either. With more CO2 present, crops seem to grow faster and bigger, thereby providing more food for an increasing population.
Before you get too excited, though, there’s a major caveat: the same food that is grown in these conditions is less nutritious. Is it really beneficial to produce more wheat, rice and other grains if these staples simultaneously provide less nourishment for the people eating them?
The School of Public Health at Harvard led a series of experiments throughout the world to see how crops might change in atmospheres with higher concentrations of carbon dioxide. Researchers replicated conditions they anticipate 50 years from now (an increase to over 500 parts carbon dioxide per million from today’s 400) by using carbon dioxide jets.
In addition to noting the larger crop output, the researchers also made sure to examine the quality of the produce. “What we found were 5 to 10 percent reductions in nutrients like iron, zinc, and protein,” said Samuel Myers, one of the lead researchers affiliated with Harvard.
Why are the nutrients decreasing in environments with higher carbon dioxide? The researchers were unable to reach a conclusion based on their research, but the leading theory is that the larger plants are stretching the available nutrients thinner, thus making them less potent.
Nearly a third of the planet’s population already lacks sufficient zinc and iron in their food supply; humanity’s collective health suffers significantly as a result. Experts estimate that current nutrient deficiencies cost the world population a total of 63 million years of life each year.
One of the main reasons for widespread malnutrition is access to and affordability of foods with substantial nutritional value. Since grain and rice crops are all some people can realistically eat, having these particular foods lose some of its nutritional content is troubling since, with fewer nutrients to go around, the malnutrition problem will only be compounded.
From a big picture perspective, this could legitimately be global warming’s most devastating consequence for humanity that we know of yet. Scientists expect that climate change will also decrease biodiversity and the number of plant species available, meaning that an even greater number of people will depend on grains as their main source of food.