V. Ramanatha Rao, C.L. Laxmipathi Gowda, S.V. Raghuram Shetty, M.J. Vasudeva Rao, D.R. Mohan Raj
Given greater awareness of environmental degradation, research in recent years has focussed on how different facets of human activity contribute to climate change and/or biodiversity loss. In that context, some studies have attempted to analyse the biodiversity footprint of various agricultural products, with the aim of potentially reducing the consumption of food products with a high biodiversity footprint. (Note: Biodiversity footprint is a metric used to estimate biodiversity loss; a higher footprint would imply a greater loss of biodiversity.)
A recent study (Cheng et al. 2024, https://doi.org/10.1371/journal.pone.0296492) analyses individual dishes from several countries, and it reports that vegan and vegetarian dishes have a relatively high biodiversity footprints, even though it is less than that caused by dishes containing meat. The Indian press has picked this up, leading to unusually high coverage about vegetarian dishes and Indian staples, such as idly andrajma, as having significant biodiversity footprints. Surely, analysing 151 dishes from across the world for their biodiversity footprint is not a simple matter, and it brings into question the need for such studies, which divert attention from more significant contributors, such as mining and logging (both legal and illegal), that lead to increased deforestation and land-use changes. Of particular concern is the way this one single paper was talked about in the Indian press (we are not aware of any other country where such a coverage was accorded to it).
The findings of the study need to be examined in a wider context.
Issues related to environmental degradation and biodiversity loss have led to several international agreements, whereby countries have been set targets to mitigate the ill-effects of human activities, including food-production systems. While biodiversity, which includes agricultural biodiversity, is the backbone of a healthy food system, numerous studies have identified agricultural production systems (often lumped together with livestock production and food waste) as a major driver of climate change and biodiversity loss. Among other industries seen as causing biodiversity are fossil fuels, the fashion industry, transport, and construction (see https://climatetrade.com/the-worlds-most-polluting-industries/#:~:text=1%20%E2%80%93%20Fossil%20fuels%20%E2%80%93%20It%20is,reaching%2040.5%20gigatons%20of%20CO2).
Although knowledge on which agricultural products negatively impact the environment and/or biodiversity help in making food systems sustainable, care must be taken to differentiate between staples that are essential for human existence and other activities which may not be equally so. When we critically examine food systems, we need to maintain a balanced perspective and avoid drastic measures, based on studies conducted in a hurry, to recommend changes in dietary habits that promote sustainability. Based on the study by Cheng et al, for example, one can infer that dishes such as idly be avoided, ignoring its useful role in human health and nutrition. More than 3.5 billion people globally depend on rice for at least 20% of their daily calory intake. Globally, rice provides 15% of protein and 21% of human energy requirements per capita. Similarly, legumes are the main source of protein for billions of people. Thus, the findings of the study need to be understood in the context of the broader demographic, human, as well as environmental, implications.
Several earlier studies have shown that production of chicken, meat, pork, and beef needs more water and leaves a larger carbon footprint than producing crops such as wheat and maize. In this context, it is likely that lobbyists of the meat industry in the developed world, with vested interests and their own bias, are attacking the traditional food systems of poorer countries, where it is still a subsistence activity to feed the family first, and where only the surplus, if any, is marketed.
While the information provided by Cheng et al. (2024) is useful, any decisions/recommendations regarding dietary changes should be based on comprehensive and repeatable studies that consider the broader environmental and human impacts. The environmental footprint of a product is a science-based measure of its overall environmental performance, encompassing factors such as emissions, resource use, land and water use, and impacts on water, air, and soil. Agriculture certainly plays a role in these environmental aspects, with products like beef and pork, as well as crops like rice, having significant environmental and biodiversity footprints. But since food is an essential commodity, any changes in consumption patterns should be approached thoughtfully and with consideration for food security.
Further studies may be needed to validate the findings of Cheng et al, to ensure that all relevant factors are considered. For example, the variety of ingredients used in traditional dishes, such as sambar and chutney(generally used as side dishes with idly) can contribute not only to biodiversity conservation on-farm of different plant species, but also enhanced nutrition.
In conclusion, we need to approach the findings of Cheng et al. with caution, and to carry out further studies that can provide more informed guidance to policymakers. In addition, we urge the research community to focus more on those human activities that have greater environmental impacts than crop production and consumption. While efforts must continue to make agriculture and food systems more sustainable and resilient, attention must shift also to other human activities, such as mining and logging, which are less essential for human survival than food production and consumption, so as to identify and reduce their role in environmental degradation.