Q: What is the sustainable diet index?

A: The Sustainable Diet Index (SDI) is used to assess the environmental, health, and social impacts of dietary choices. It helps measure how well a diet aligns with sustainability principles, balancing nutrition with ecological responsibility.

The SDI evaluates diets based on factors such as carbon footprint, water usage, biodiversity impact, and nutritional adequacy. A high SDI score indicates a diet that supports human health and environmental sustain- ability. Plant-based diets, for example, tend to rank higher due to their lower greenhouse gas emissions and reduced land and water use. Conversely, diets high in red meat and processed foods score lower because of their significant environmental impact.

The SDI aims to guide individuals, organizations, and governments in making informed dietary choices that contribute to global food security and climate change mitigation. By adopting diets with a higher SDI, people can help promote a more sustainable food system while improving personal health.

Incorporating more plant-based foods, reducing waste, and choosing local, seasonal ingredients are simple steps to improve one’s SDI score and contribute to a healthier planet.

(Environmental Nutrition is the award-winning independent newsletter written by nutrition experts dedicated to providing readers up-to-date, accurate information about health and nutrition in clear, concise English. For more information, visit www.environmentalnutrition.com.)

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