By Alan Dangour, MSc PhD RNutr, London School of Hygiene & Tropical Medicine; Francesca Harris, MSc, London School of Hygiene & Tropical Medicine; Benjamin Kayatz, MSc, University of Aberdeen; and Jon Hiller, PhD, University of Edinburgh
With a population of 1.2 billion people and rapidly changing dietary habits, the health and environmental impacts of diets in India is a major area for research. In 2015 our research team, began studying diets in India by using the Cool Farm Tool to calculate greenhouse gas emissions of sixteen plant-based foods and four foods of animal origin. We used these to estimate the carbon footprint of diverse diets and compared them among different population groups. We found that rice-based diets (typically consumed in the South of India) generally had higher greenhouse gas emissions than wheat-based diets (consumed in the North). Younger adults living in cities consumed more animal products, such as milk and mutton, and had higher dietary carbon footprints than older populations living in rural areas and typically consuming more pulses and grains.
To this GHG analysis, we then added an analysis of water footprints of Indian diets. We worked with others to develop the new Cool Farm Tool Water module, that calculates on-farm water footprints of crops and are now applying this module to estimate state level water “foodprints” in India. Our current estimates for the five major cereal crops (rice, wheat, maize, millet and sorghum) compare well to previous estimates from the Water Footprint Network. Our estimates allow us to understand the water requirements of the major cereal crops in the 32 States of India and review intra and inter-annual trends. We will expand this work to include other major crops in the near future.
Since 2015, researchers from the London School of Hygiene & Tropical Medicine and University of Aberdeen have partnered on the Sustainable and Healthy Diets in India (SAHDI) funded by the Wellcome Trust. With a growing population and a rapidly developing economy, Indian food production is under significant pressure to meet changing and increasing dietary needs. However, agricultural land is already reaching its upper limits, rainfall is becoming erratic and groundwater resources are depleted. The SAHDI project set out to estimate the environmental impacts of diverse diets in India, and identify whether realistic dietary changes might support both human health and the environment.
The production of food for human diets creates roughly 25% of global greenhouse gas emissions and accounts for approximately 70% of total water use. To achieve global environment goals, such as those set by the Paris Climate Agreement, agricultural practices need to become more sustainable but significant changes are also needed in how we consume food: wasting less, and eating more environmentally sustainable and healthy diets. Globally diets are changing rapidly and now typically contain more dietary energy, saturated fat, sugar and salt, and increasing amounts of foods of animal origin. Current research suggests that improved diets would improve health and simultaneously benefits the environment.
Thanks to the Cool Farm Tool, the SAHDI project has been able to provide important and timely research on environmental “foodprints” in India. Improving agricultural practices is critical to reducing environmental impacts of the global food systems, but food consumption is just as important.