The Health and Environmental Impacts, Safety, and Affordability of the EAT-Lancet Planetary Health Diet: A Multidisciplinary Systematic Review and Meta-Analysis

In 2019, the EAT-Lancet Commission proposed transition to the planetary health diet, whereas the health and environmental benefits, safety, and affordability of the diet have recently been challenged. This systematic review and meta-analysis aimed to provide a quantitative summary of the EAT-Lancet diet and population health and environmental sustainability; and to review safety (nutrient deficiencies) and affordability of the diet. We searched PubMed, Embase, Web of Science, CINAHL, Cochrane Library, and ClinicalTrials.gov from 1 January 2019 to 19 June 2025 for quantitative studies. Of the eligible studies, epidemiological studies on population health or environmental sustainability were further used for meta-analysis. The risk of bias of the included studies was assessed using the Newcastle–Ottawa Scale tool. A total of 227 studies were included in the systematic review and 79 of them were used for the meta-analysis. Most prospective cohort studies and half the cross-sectional studies were of high quality. The EAT-Lancet diet was associated with lower risks of all-cause mortality [pooled hazard ratio = 0.80, 95% confidence interval (CI): 0.76, 0.85; n = 17, 1,063,289 participants], cardiovascular disease (0.83, 95% CI: 0.74, 0.94; n = 10, 1,027,822 participants), and type 2 diabetes, but not risks of all cancers or dementia. The EAT-Lancet diet was associated with a reduction of 1.55 (0.22, 2.89) kg CO 2 eq/d/person of greenhouse gas emission ( n = 12, 882,673 participants), whereas no strong evidence supported the benefits to water or land use. On a global average, the EAT-Lancet diet would induce deficiencies in vitamin B 12 , calcium, iron, and zinc in adults, especially in pregnant women. Globally, 1.6–3.0 billion people were not able to afford the diet. In conclusion, adoption of the EAT-Lancet diet may modestly reduce global chronic disease and environmental burden, whereas nutrient deficiencies and economic inequality across regions should be addressed before dietary transition. Trial registration number This study was registered at PROSPERO as CRD42024540867 (URL of registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD42024540867 ).