The importance of healthy diets is woven into the fabric of the Sustainable Development Goals, although there is no clear metric to define it. Employing a simulation model (MAGNET), this study examines the sustainability implications arising from the adoption of recommended daily nutrition requirements inspired by the ‘Lancet’ reference diet. To measure sustainability, changes in ‘virtual’ requirements and associated tier footprints for irrigation (blue) water, agricultural land and greenhouse gas emissions (GHG) are calculated. Assuming business-as-usual food consumption trends, between 2015 and 2050 blue water, agricultural land and emissions rise 34%, 9% and 44%, respectively, whilst corresponding increases in Sub-Saharan Africa are much higher. By 2050, the switch to the reference diet decreases agricultural land use by -8% and emissions by -9%. Global blue water and cropland requirements increase by 5%, whilst significant concomitant savings in permanent pastureland (-21%) are expected. By region, the diet switch drives rising blue water consumption in Oceania and the EU and agricultural land savings in Latin America and Oceania, accompanied by cropland increases in the EU and North Africa. The reference diet generates substantial reductions in GHG emissions, particularly in Latin America. Interestingly, Sub-Saharan Africa which abstains from the reference diet due to affordability considerations, benefits from a ‘rebound’ effect from falling meat and dairy prices. Finally, the diet shift could result in marginal per capita food expenditure rises arising from demand driven fish price, particularly in more vulnerable world regions. This estimate does not capture, however, second-round economic growth effects arising from increased labour productivity and reduced public health expenditures.

尽管没有明确的衡量标准，健康饮食的重要性已融入可持续发展目标的结构中。本研究使用模拟模型（MAGNET），研究了从“柳叶刀”参考饮食的启发中采纳建议的每日营养需求所产生的可持续性影响。为了衡量可持续性，计算了灌溉（蓝色），农业用地和温室气体排放量（GHG）的“虚拟”要求和相关层级足迹的变化。假设日常食品消费趋势保持不变，2015年至2050年期间，蓝色水，农业用地和排放量分别增加34％，9％和44％，而撒哈拉以南非洲的相应增加量要高得多。到2050年，改用参考饮食可以减少-8％的农业土地使用量和-9％的排放量。全球蓝色水和农田的需求量增加了5％，与此同时，预计永久草场也将大量节省下来（-21％）。按地区划分，饮食结构的变化促使大洋洲和欧盟的蓝色水消耗量增加，拉丁美洲和大洋洲的农业土地节省量增加，同时欧盟和北非的耕地增加。参考饮食可显着减少温室气体排放，特别是在拉丁美洲。有趣的是，出于负担能力的考虑，撒哈拉以南非洲国家放弃了参考饮食，但受益于肉类和奶制品价格下跌的“反弹”效应。最后，饮食结构的变化可能会导致由需求驱动的鱼价引起的人均粮食支出的增加，特别是在世界上较脆弱的地区。但是，该估计数并未反映出劳动生产率提高和公共卫生支出减少所带来的第二轮经济增长影响。