Comparing environmental and personal health impacts of individual food choices.

Dietary choices affect personal health and environmental impacts, but little is known about the relation between these outcomes. Here we examine the intake-related health impacts and the food-production related impacts to ecosystems and human health by applying life cycle impact assessment methods to habitual diet data of 1457 European adults. We measured food production impacts for each individual in terms of Disability Adjusted Life Years (DALYs) as calculated by the Recipe 2016 life cycle impact assessment method using secondary production data, which were then compared with their personal health DALYs predicted from the known relationships between dietary choices and disease risk. Across this population cohort, each individual was estimated to lose on average 2.5 ± 0.9 DALYs per lifetime due to sub-optimal dietary intake (with seed and vegetable under-consumption the greatest contributors) and their food choices caused environmental human health impacts of 2.4 ± 1.3 DALYs (particularly due to the damage associated with production of meats, milk, and vegetables). Overall, there was no relationship between a healthier dietary pattern and the environmental human health impacts associated with production of its constituent foods (i.e. healthier diets did not have lower or higher production impacts). This was due to a combination of decreased meat consumption correlating with increased consumption of other foods, as well as the fact that under-consumption of some low impact foods yielded high personal health consequences. However, for specific food items synergies and tradeoffs could be identified. For example, reduced processed meat consumption benefits both personal and environmental health. Every DALY caused by higher whole grain and vegetable production and consumption would be offset by reduced disease risk that equated to an average of 7.7 (5.7 to 10.4) and 1.4 (0.9 to 2.5) lower personal health DALYs, respectively.