Hidden shift of the ionome of plants exposed to elevated CO2 depletes minerals at the base of human nutrition
Mineral malnutrition stemming from undiversified plant-based diets is a top global challenge. In C3 plants (e.g., rice, wheat), elevated concentrations of atmospheric carbon dioxide (eCO2) reduce protein and nitrogen concentrations, and can increase the total nonstructural carbohydrates (TNC; mainly starch, sugars). However, contradictory findings have obscured the effect of eCO2 on the ionome - the mineral and trace-element composition - of plants. Consequently, CO2-induced shifts in plant quality have been ignored in the estimation of the impact of global change on humans. This study shows that eCO2 reduces the overall mineral concentrations (-8%, 95% confidence interval: -9.1 to -6.9, p<0.00001) and increases TNC:minerals > carbon:minerals in C3 plants. The meta-analysis of 7,761 observations, including 2,264 observations at state of the art FACE centers, covers 130 species/cultivars. The attained statistical power reveals that the shift is systemic and global. Its potential to exacerbate the prevalence of 'hidden hunger' and obesity is discussed.
Article and author information
- Ian T Baldwin, Max Planck Institute for Chemical Ecology, Germany
- Received: January 8, 2014
- Accepted: April 25, 2014
- Accepted Manuscript published: May 7, 2014 (version 1)
- Accepted Manuscript updated: May 13, 2014 (version 2)
- Version of Record published: May 27, 2014 (version 3)
© 2014, Loladze & Baldwin
This article is distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use and redistribution provided that the original author and source are credited.
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