Measurement of diets that are healthy, environmentally sustainable, affordable, and equitable: A scoping review of metrics, findings, and research gaps

Abstract

IntroductionResearch on the impacts of dietary patterns on human and planetary health is a rapidly growing field. A wide range of metrics, datasets, and analytical techniques has been used to explore the role of dietary choices/constraints in driving greenhouse gas (GHG) emissions, environmental degradation, health and disease outcomes, and the affordability of food baskets. Many argue that each domain is important, but few have tackled all simultaneously in analyzing diet-outcome relationships.MethodsThis paper reviews studies published between January 2015 and December 2021 (inclusive) that examined dietary patterns in relation to at least two of the following four thematic pillars: (i) planetary health, including, climate change, environmental quality, and natural resource impacts, (ii) human health and disease, (iii) economic outcomes, including diet cost/affordability, and (iv) social outcomes, e.g., wages, working conditions, and culturally relevant diets. We systematically screened 2,425 publications by title and abstract and included data from 42 eligible publications in this review.ResultsMost dietary patterns used were statistically estimated or simulated rather than observed. A rising number of studies consider the cost/affordability of dietary scenarios in relation to optimized environmental and health outcomes. However, only six publications incorporate social sustainability outcomes, which represents an under-explored dimension of food system concerns.DiscussionThis review suggests a need for (i) transparency and clarity in datasets used and analytical methods; (ii) explicit integration of indicators and metrics linking social and economic issues to the commonly assessed diet-climate-planetary ecology relationships; (iii) inclusion of data and researchers from low- and middle-income countries; (iv) inclusion of processed food products to reflect the reality of consumer choices globally; and (v) attention to the implications of findings for policymakers. Better understanding is urgently needed on dietary impacts on all relevant human and planetary domains simultaneously.

Augmenting the National Nutrition Data System to Promote Diet Sustainability Analyses

“…The United States food system also accounts for over one-quarter of freshwater withdrawals and land use, and over 10% of fossil fuel use [ 9 ]. Concerns about safe working environments are also emerging [ 11 ], as well as other indicators of social sustainability such as food availability and cultural acceptability [ 12 ]. These impacts vary tremendously by which commodities are produced for human consumption [ 11 , 13 , 14 ] and dietary shifts are urgently needed to bring the United States and global food systems within planetary boundaries [ 15 , 16 ].…”

“…Yet recent studies have pointed to a lack of sustainability metrics and methods that are hindering further research and policy progress [ 12 , 22 , 23 ]. The National Strategy on Hunger, Nutrition, and Health (hereafter, the National Strategy), released by the White House in September 2022, aims to fill this gap.…”

“…Social sustainability is concerned with measuring impacts on people, such as equity, social well-being, ethics, inter-individual interactions, and societal functions [ 96 ], and remains 1 of the most understudied domains of sustainability [ 12 ]. This domain can be measured using exposure metrics such as demographic and behavioral characteristics as well as outcome metrics such as forced labor [ 97 ] and animal welfare [ 98 ].…”

“…This domain can be measured using exposure metrics such as demographic and behavioral characteristics as well as outcome metrics such as forced labor [ 97 ] and animal welfare [ 98 ]. Demographic and behavioral characteristics are important exposure variables that can provide information on disparities in outcomes such as food access, food availability, and social risk that would otherwise be hidden by population averages [ 12 ]. Others have used FCID in conjunction with NHANES and other dietary surveys to evaluate these exposure metrics, including differences in food and nutrient intake by demographic characteristics such as age, sex, income, race, ethnicity, educational attainment, and others [ 59 , 60 , 62 , 64 , 65 , [68] , [69] , [70] , [71] , [72] , [73] , [74] , 82 , 84 ], as well as behavioral characteristics such as smoking, exercise, and diet knowledge and behaviors [ 62 , 66 ].…”