Climate change will reduce the nutritional quality of diets from staple crops in Africa and globally

Drought-tolerant beans at a Climate-Smart Village site in Wote, Makueni Kenya. Photo: C. Schubert (CCAFS)
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Release date

Thursday, November 1, 2018

GALWAY, Nov. 1 2018 -- Research conducted by scientists at the National University of Ireland Galway (NUI Galway) in collaboration with the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) has revealed that climate change will reduce the nutritional quality of one of the world’s major staple crops, the common bean.The research, published today in the journal Scientific Reports, indicates that both the nutritional quality and the yields of common bean will be reduced under the climate change-induced drought stresses that will occur in southeastern Africa by 2050.

The scientists conducted crop modelling, combined with field trials and molecular lab experiments, to analyse the yields and the nutritional quality of the crop. The crop modelling analysis revealed that the majority of current common bean growing areas in southeastern Africa will become unsuitable for bean cultivation by the year 2050. They further demonstrated reductions in yields of available common bean varieties in field trial experiments at a climate analogue site representative of future predicted drought conditions.  

The nutritional analysis of the different common bean varieties, grown under the level of drought stress expected under climate change scenarios, revealed that important micronutrients for human health (e.g. iron) were reduced in all of the varieties, while antinutritional compounts such as phytic acid and lead were increased.

The NUI Galway research, funded by Irish Aid, Science Foundation Ireland (SFI) and CCAFS, indicates that under climate change-induced drought scenarios, future bean servings by 2050 will likely have lower nutritional quality, posing challenges for ongoing climate-proofing of bean production for yields, nutritional quality, human health, and food security.

Lead scientist for the study, Prof Charles Spillane (Director of the Ryan Institute at NUI Galway) said of the research, “Our research, and recent research by other groups, is generating an emerging body of evidence that climate change will reduce the nutritional quality of many of the world’s staple crops due to the effects of rising temperatures, reduced rainfall and rising CO2 levels on the nutritional composition of the crop-derived foods that underpin global food security and human health. As it takes decades to develop and disseminate new crop varieties, major investment is needed now to climate-proof our crops and cropping systems so that both their yields and nutritional quality can be resilient to future climate change stresses. Our results highlight the need for accelerated development and seed system dissemination of heat- and drought-tolerant common bean varieties that can maintain yields while also improving nutritional quality (e.g. via biofortification breeding) under future climate change scenarios.”

NUI Galway PhD students Marijke Hummel and Brendan Hallahan indicated that “Dietary deficiencies of micronutrients such as iron constitute major public health problems globally, particularly amongst women and children in sub-Saharan Africa. The FAO’s 2018 State of Food Security & Nutrition in the world has indicated that for the third year in a row there has been a rise in world hunger, where climate climate variability and extremes are now a key force behind the recent rise in global hunger.  In addition to negative impacts on crop yields, our group’s research reveals that the nutritional quality of our crop-derived foods will decline under climate change stresses, which will most heavily impact on the poorest and most nutritionally secure in our societies.”

Dr. Andy Jarvis from CCAFS stressed that “As our diets are wholly dependent on plants, there is major cause for concern if climate change leads to lower levels of essential nutrients such as protein, iron and zinc in our diets by 2050. Such loss of dietary nutrients in foods will further aggravate the nutritional deficiency experienced by hundreds of millions of people, particularly the poorest in developing countries in Asia, the Middle East, and North Africa.”

The research was conducted between Malawi and Ireland as a collaboration between NUI Galway, CCAFS and the International Center for Tropical Agriculture (CIAT). NUI Galway is one of the 13 strategic research partners for CCAFS. 

UPDATE: Paper citation and link - Hummel M, Hallahan B, Brychkova G, Ramirez-Villegas J, Guwela V, Chataika B, Curley E, McKeown P, Morrison L, Talsma E, Beebe S, Jarvis A, Chirwa R, Spillane C. 2018. Decline in nutritional quality of common bean under climate change induced drought stress in Africa. Scientific Reports 8: 16187. https://doi.org/10.1038/s41598-018-33952-4


For more information contact:

Professor Charles Spillane, Director of Ryan Institute, NUI Galway at charles.spillane@nuigalway.ie

For press contact: 

Gwen O’Sullivan, Press & Information Executive, NUI Galway at gwen.osullivan@nuigalway.ie or +353 91 495695.