Environmentally sustainable diets and human health - Nutritional adequacy, disease risk, and mortality

Introduction: Food systems strongly influence both human and planetary health. Unhealthy diets aremajor risk factors for chronic disease and mortality, while food production contributes substantially togreenhouse gas emissions (GHGE), and other negative environmental impacts. Adopting moresustainable dietary patterns, such as the EAT-Lancet diet, has been proposed as part of the solution, butuncertainties remain regarding their long-term health effects, nutri-tional adequacy, and optimal methodsfor assessment.Aim: The aim of this thesis was to examine associations between environmentally sustainable diets,nutritional adequacy, and major health outcomes, with a focus on mortality, cardiovascular disease,diabetes, and micronutrient intake and status.Methods: The analyses were mainly based on the Malmö Diet and Cancer Study, including about 26,000adults followed for up to 30 years. Dietary intake was assessed using a validated diet history methodcombining a 7-day food diary, questionnaire, and interview. Health outcomes were retrieved from nationalregisters. Nutrient adequacy was evaluated using both dietary data and blood biomarkers. Life cycleassessment (LCA) was used to estimate dietary GHGE, and adherence to the EAT-Lancet diet wasassessed using dietary scores.Results: Higher adherence to the EAT-Lancet diet was associated with lower risks of mortality, reducedstroke risk, and lower GHGE. Lower dietary GHGE were most consistently associated with decreasedrisk of diabetes, while associations with mortality were weaker and partly non-linear. Diets with lowerenvironmental impact were generally compatible with adequate micronutrient intake and status and weresometimes linked to nutritional benefits, such as a reduced risk of folate deficiency, though a slightlyhigher risk of anaemia was observed.Conclusion: Environmentally sustainable diets can promote health, reduce mor-tality, and do notsubstantially increase the risk of micronutrient deficiencies. These findings underscore the co-benefits ofaligning nutrition and climate poli-cies and support the integration of sustainability into dietary guidelines.