Sustainability assessment of Indian diets: a modelling study

Background: Transitioning from current to sustainable diets that have low environmental impacts and high nutrition and are culturally acceptable can contribute greatly towards the achievement of several national Sustainable Development Goals (SDGs). With a population of 1·3 billion, widely prevalent malnutrition and increasing incomes, India's per capita consumption patterns will also play a key role over next decade in deciding the fate of United Nations 2030 global SDGs. Methods: Here we assess how the intake amounts of different food items in Indian diets must change in order to the meet the daily-recommended levels for 29 macro and micro nutrients while maintaining environmental footprints below the five food-related per capita planetary boundaries (carbon emissions, water, land, nitrogen and phosphorus use). We also put several cultural acceptability constraints to avoid obtaining an unrealistic diet. Findings: A considerable departure from current dietary behaviour is needed to transition from current to sustainable diets in India. While the daily per capita environmental footprints of current Indian diets are well below the respective planetary boundaries, the daily recommended levels for vitamins B12, E, and K, fibre, potassium, and choline are not being met currently, suggesting the need to pay special attention to them. The required changes include high increases (>200 g per capita per day) in fruits and vegetable intake, moderate increases in the intake of other grains (eg, millet, sorghum, rye), pulses, roots and tubers, fish and meat (about 30 g each) and a high reduction in intake of rice and dairy products (>100 g each). Interpretation: Future research should assess the potential of different leverage points from both the production side (eg, reducing food loss, filling yield gaps, improving technologies, biofortification) and the consumption side (eg, taxes, subsidies, campaigns, changes in physical microenvironment) to help transition towards sustainable diets. Funding: Initiation Grant of IIT Kanpur, India (number 2018386).