Summary
This paper, published in Nature in 2014, synthesises data from free-air CO₂ enrichment (FACE) experiments to demonstrate that rising atmospheric CO₂ concentrations reduce the nutritional quality of key staple crops, including wheat, rice, maize, and soybeans. The authors estimate that several hundred million people — predominantly in the Global South — face heightened risk of zinc and iron deficiency as a consequence of these changes. The study represents a significant contribution to understanding how climate change may undermine food security through nutritional pathways, not solely through yield impacts.
UK applicability
Whilst the most acute risks identified apply to populations in South and Southeast Asia and sub-Saharan Africa where dietary reliance on staple grains is highest, the findings are relevant to UK agricultural policy and public health planning insofar as UK wheat quality and global food supply chains are affected by CO₂-driven nutrient dilution.
Key measures
Grain zinc concentration (mg/kg); grain iron concentration (mg/kg); grain protein concentration (%); estimated population at risk of micronutrient deficiency
Outcomes reported
The study examined changes in the concentrations of zinc, iron, and protein in major staple crops grown under elevated CO₂ conditions, finding statistically significant reductions across wheat, rice, and other staples. It estimated the potential population-level nutritional risk, particularly in regions already vulnerable to micronutrient deficiency.
Topic tags
Dig deeper with Pulse AI.
Pulse AI has read the whole catalogue. Ask about this record, its theme, or how the findings apply to UK farming and policy — every answer cites the underlying studies.