Despite the inadequate level of mainstream attention and action taken towards this issue, climate change is arguably the most important global issue of the century. A large body of research exists that provides insight into how climate change impacts food, and public health. This insight provides the relevance of climate change to the profession of nutrition and dietetics, and further, the basis upon which to petition the profession to act now. Below are four things you need to know about climate change and how it affects food, nutrition and health.
Climate change is real, and so are its impacts. In the past century, human activity has contributed to the climate changing in such a way that has warmed the Earth by 1.5°F since 1900. The main contributor of global warming is human-induced greenhouse gas (GHG) emissions, primarily CO2, which have increased from 280ppm to 400ppm during the same time (Romm, 2016). Scenario-based projections estimate that CO2 levels will reach 540ppm – 958ppm by 2100 and will be accompanied by more frequent and intense extreme weather events such as droughts, deluges and storm surges. In addition to environmental disruptions, climate change has demonstrated the ability to disrupt healthcare and food system infrastructures. In the societal backdrop of food and water security, food safety, sustainability, and the chronic disease crisis, it is ever more important to note that climate change and its environmental impacts will only exacerbate these social stressors.
Climate change impacts food insecurity. A paper by Lake et al. offers a pathway demonstrating how climate change affects food security in developed countries. Human-induced GHG emissions such as that contributed by the U.S. food system lead to global warming, sea level rise and extreme weather events. These ecosystem changes have downstream effects exhibited by agricultural and food system changes as seen in production and distribution which ultimately affects food availability, accessibility, and affordability (Lake et al., 2012). In the presence of decreased availability, accessibility and affordability of quality, nutrient-dense foods, individuals will opt for more readily available, highly-processed and calorically-dense foods associated with chronic disease risk and poor health outcomes.
Climate change impacts nutrition and public health. Several studies support the connection between climate change and crop production, nutrient composition, food safety and public health. One study reported a link between climate change impacts and a decrease in global maize and wheat production by 3.8% and 5.5%, respectively, since 1980 (Lobell et. al, 2011 & 2013). Elevated CO2 levels were found to reduce levels of protein and important minerals in plants while increasing the starch content (Loladze et. al, 2014 & Myers et. al, 2014). Food safety is also impacted by climate change as grain quality after harvest may deteriorate as a result of increased temperature and moisture that promote mold and mycotoxin growth (Chakraborty et. al, 2011). An article in the International Journal of Public Health asserts that “climate change will have a negative impact on physiological functions in cardiovascular and kidney diseases” and posits that “chronic disease risks are likely to increase with climate change and related increase in air pollution, malnutrition, and extreme weather events” (Kjellstrom et al., 2010).
Climate change impacts the nutrition and dietetics profession. Decreased nutritional value of crops could potentially have significant public health implications since dietary guidance recommendations promote plant-based eating patterns to combat the chronic disease crisis and improve public health outcomes. Nutrients of public health concern include calcium and iron, both of which have been shown to decrease with elevated CO2 levels. Finally, Loladze argues that “a diet that is deficient in minerals and other nutrients can cause malnutrition, even if a person consumes enough calories” and that “these changes might contribute to the rise in obesity, as people eat increasingly starchy plant-based foods, and eat more to compensate for the lower mineral levels found in crops” (Loladze et. al, 2014). In sum, the direct impacts of climate change on food, nutrition and health underscore the relevance of this issue to our profession and demonstrates the need to increase awareness, advance research and take action to mitigate climate change and promote health.
Chakraborty, S., & Newton, A. C. (2011). Climate change, plant diseases and food security: an overview. Plant Pathology, 60(1), 2-14.
Kjellstrom, T., Butler, A. J., Lucas, R. M., & Bonita, R. (2010). Public health impact of global heating due to climate change: potential effects on chronic non-communicable diseases. International journal of public health, 55(2), 97-103.
Lake, I. R., Hooper, L., Abdelhamid, A., Bentham, G., Boxall, A. B., Draper, A., … & Waldron, K. W. (2012). Climate change and food security: health impacts in developed countries. Environmental Health Perspectives, 120(11), 1520.
Lobell, D. B., Schlenker, W., & Costa-Roberts, J. (2011). Climate trends and global crop production since 1980. Science, 333(6042), 616-620.
Lobell, D. B., Hammer, G. L., McLean, G., Messina, C., Roberts, M. J., & Schlenker, W. (2013). The critical role of extreme heat for maize production in the United States. Nature Climate Change, 3(5), 497.
Loladze, I. (2014). Hidden shift of the ionome of plants exposed to elevated CO2 depletes minerals at the base of human nutrition. Elife, 3.
Myers, S. S., Zanobetti, A., Kloog, I., Huybers, P., Leakey, A. D., Bloom, A. J., … & Holbrook, N. M. (2014). Increasing CO 2 threatens human nutrition. Nature, 510(7503), 139.
Romm, J. (2018). Climate Change: What Everyone Needs to Know®. Oxford University Press.