Climate Change’s Effect on the Nutritional Density of Food

Various studies have come to show that increased levels of CO2 in the atmosphere are likely to have an immense impact on plants and food all over the world, one of which being significant nutrient reduction.

In one study published in the American Association for The Advancement of Science, different varieties of rice plants were exposed to high levels of CO2 to simulate amounts similar to what is expected to be in our atmosphere at the end of the century. To mimic environmental conditions, researchers performing the study installed pipes into small open-air growing plots to distribute the elevated levels of CO2.

As many of us have learned, CO2 is a required component for photosynthesis in plants, which is why it seems trivial to think that heightened levels of CO2 would be harmful to plants. However, scientists have found that plants’ absorption of nutrients from the soil and air are integral to its chemical makeup. When the balance is shifted, the plants can have adverse reactions, thus causing nutrient levels to fluctuate. 

According to Brad Plumer of the New York Times, “Most of the 18 varieties [exposed to CO2] of rice that were grown and harvested contained significantly less protein, iron and zinc than rice that is grown today. All of the rice varieties saw dramatic declines in vitamins B1, B2, B5 and B9, though they contained higher levels of vitamin E.” Some genotypes were affected nutritionally more than others, and scientists are having a difficult time dissecting this matter since each variety had shown declining numbers of vitamin B. Rice was chosen as a subject of interest for the study predominantly because more than 2 billion people worldwide rely on rice as their primary food source.

To counteract the changes that we will likely see from heightened CO2, scientists may work to engineer plants that will be less sensitive and capable of maintaining nutritional value with higher-than-normal CO2 exposure. Another potential counteraction would be limiting the amounts of CO2 that we as humans consume, of which the root is burning fossil fuels.

Dr. Myers, a research scientist at Harvard University Center for the Environment and active player in leading studies, says it best, “…I think we should continue to expect surprises. We are completely altering the biophysical conditions that underpin our food system, and we still have very little understanding of how those disruptions will ripple through ecosystems and affect human health.”

You can find more information on these studies at the New York Times and Science Advances.