Food justice: cultivating the field

This article provides an evidence-based review of the growing field of food justice, which seeks to understand how inequalities of race, class and gender are reproduced and contested within food systems. Analyzing a database of peer-reviewed articles and books related to food justice in the US context (n = 200), we find that food justice is a highly interdisciplinary research area organized around three central axes: social movement activism, the development of alternative food practices, and analyses of inequalities in conventional and alternative food systems. Especially since 2011, the rate of new scholarship has increased, along with increased attention from policymakers and the public to the issues of inequality in the food system. This field has developed somewhat independently of work in the physical sciences quantifying and evaluating the sustainability of local food systems, instead focusing more on social science concepts such as historic and present-day inequalities and the role of policy. However, there is room for convergence, especially as our analysis points to agro-ecology and land tenure as areas of growing interest. Considering this recent growth and potential for collaboration with physical scientists, we reflect on the development of the field to date by characterizing the field of food justice research, asking what is missing, and suggesting new directions.


Introduction
The growing field of food justice seeks to understand how inequalities of race, class and gender are reproduced and contested within food systems. Activists and researchers have brought together concepts from environmental justice, alternative agriculture, and food studies to develop the field of food justice in the last two decades (Alkon and Agyeman 2011). While there are competing understandings of food justice, we adopt Hislop's (2014) definition of the term as 'the struggle against racism, exploitation, and oppression taking place within the food system that addresses inequality's root causes both within and beyond the food chain.' Food justice encompasses many issues, including the opportunity to grow or purchase healthy food, dietrelated health disparities, access to land, and wages and working conditions in agriculture, food processing and restaurant work. But despite these varying topical areas, food justice scholarship is united by a focus on what Julian Agyeman (2013) calls 'just sustainability,' meaning the fusion of concerns for ecological sustainability and social justice.
Inequalities are present throughout the food system. White farmers have long been beneficiaries of loans and subsidies from the USDA designed to discourage over-production and enable access to new technologies. This support was historically denied to black farmers, Native American farmers, Latino/a farmers and women farmers, and all four of these groups are in various stages of the process of suing the USDA for redress (Gilbert et al 2002, Minkoff-Zern andSloat 2016). Even today, because of generational wealth, white individuals are more likely to be able to leverage social networks to access capital investments to start green food businesses (Fairlie and Robb 2008). Moreover, white farmers are more likely to be seen as the face of the food movement, and benefit from increased publicity (Reynolds and Cohen 2016). Lowly paid farm and food workers, on the other hand, are predominantly people of color, and often have little room for advancement. Many labor laws even explicitly exempt farmworkers, and the minimum wage for tipped workers has been frozen at $2.13 per hour −1 since the early 1990s. Meanwhile, communities of color are four times less likely to have a full service grocery store in the neighborhood (Hilmers et al 2012).
In response, an array of activists, community members, planners and policy makers have been working to address many of these inequalities under the banner of food justice. Non-profit organizations and social enterprises have opened farmers markets, grocery stores and community gardens in neighborhoods that formerly lacked access. Sometimes these are supported by federal policy such as the Healthy Food Financing Initiative, though at other times local groups operate independently. One of the most successful campaigns was to enable the use of food assistance like SNAP (food stamps) at farmers markets, and many states have funded programs that increase the value of food assistance spent on fresh foods. Organizations of workers throughout the food system have campaigned for increased wages and improved working conditions, often working in coalition with groups of consumers, students and others to convince the public that our notion of which foods are sustainably produced must also include the treatment of workers.
Scholars have begun to document the conditions that gave rise to the food justice movement as well as analyze its responses. Especially since 2011, the rate of new scholarship has increased, along with increased attention from policymakers and the public to the issues of inequality in the food system. Considering this recent growth and rising prominence, we reflect on the development of the field to date by characterizing the field of food justice research, asking what is missing, and suggesting new directions. The term 'food justice' originated in the United States, and for this reason, we limit our review to this context. In the global south, activists and scholars more often use the related term of 'food sovereignty,' which is rooted in the struggles of peasant farmers in the global south to resist the dominance of global agribusiness and maintain access to land and traditional farming practices.
Recent reviews of the food justice literature (Alkon 2018, Dixon 2014, Alkon 2013a) have described the scope of research and noted the field's multiple foci, which include analyzing inequalities in agriculture, processing, distribution and consumption of food; documenting the social movements and alternative practices seeking to ameliorate these inequalities; and situating the concept of food justice in broader areas of activism and scholarship. However, none of the recent reviews are evidence-based, and therefore do not provide a comprehensive analysis of trends in food justice research. Given the interdisciplinary nature and multiple emphases of the food justice literature, we must ask questions about the field's relative representation of different topics, changes in focus over time, and use of various research methods. Which disciplines are engaged in food justice research, and what methodologies are most prevalent? Is empirical food justice scholarship more focused on inequalities themselves, or the efforts to reduce them? Has the focus of food justice research shifted over time? Are there topics or methodologies which warrant greater attention in future scholarship? While existing reviews point to these questions, an evidence-based review is needed to delineate the field's existing priorities, and to identify topics and methods that warrant greater attention. Food justice scholarship can have a greater impact on policy and public discourse by filling in its methodological and topical gaps.
To provide an evidence-based review of food justice research, we analyze a body of 200 peer-reviewed articles and books related to food justice in the United States. We map the main areas of research in food justice scholarship, document trends over time, and point to promising future directions. Food justice is a highly interdisciplinary research topic, with contributions from scholars in at least 20 disciplines, and the largest share published in geography journals. The most common methodological approach is the case study of individual organizations. Three themes emerged as the central axes of food justice research: social movement activism, the development of alternative food practices like farmers markets and urban farms, and analyses of inequalities in conventional and alternative food systems.

Methods
We compiled a database of scholarship related to food justice. A search of Web of Science and Google Scholar for the phrase 'food justice' generated 271 scholarly articles and books, excluding law review articles, book reviews and non-peer reviewed publications. Based on the authors' experience, the searches were found to capture all of the seminal food justice publications as well as many related works. Using this strategy, we assume that research related to inequalities in the food system will include the term 'food justice' in a searchable format. Works that did not explicitly reference food justice, therefore, may be excluded from our sample. This is a limitation of the findings, discussed more in the conclusion. We chose to eliminate articles and books with a non-US focus, because research internationally has proceeded at a different pace, and with a different emphasis, than the field of food justice in the United States. The resulting US sample (N = 200) included scholarly articles and books published between 2000 and 2017.
We coded the works for their author(s), year of publication, journal discipline (for articles), and several factors related to the methodology and content. Examining key sections including the abstract (for articles), table of contents (for books), introduction, and conclusion, we coded the works on several dimensions: whether the works reported on original empirical research (meaning gathering and analyzing data as opposed to theoretical or descriptive work); what research methods were used (if empirical); unit of analysis (if empirical); and topics addressed. Drawing from the authors' experiences and earlier literature reviews, we hypothesized that the body of research would likely focus on major topics related to inequality in the food system: race/ethnicity, class, gender, labor/work, food access, policy, land use, social movements, and alternative practices. Upon examining the articles, we added urban agriculture and youth as additional dimensions. We created binary variables for each of these dimensions, and coded publications with a 1 for each if they included discussion of the topic as an independent or dependent variable, or as the unit of analysis. Based on questions arising from earlier reviews, we also noted whether empirical research addressed practices in agricultural production, processing, distribution, and/or consumption of food, and whether the research related to rural and/or urban issues. We also noted the research method(s) used for the empirically-driven journal articles (N = 113). Because many of the articles employed multiple methods, we created binary variables for each research method that appeared in the sample 4 rather than creating one categorical variable for research method.
After coding the sample, we used Stata to describe the data and analyze trends over time. We acquired summary statistics for each binary variable to determine what percent of the publications related to each topic or employed each research method. Using logistic regression of each binary variable on publication year, we assessed the trends in topics and methods over time.

Results
Characterizing the field Food justice is a highly interdisciplinary research field. Our sample included 49 articles published in interdisciplinary journals (24.5% of the sample), and an additional 28 articles (14%) published in journals dedicated to specific interdisciplinary topics (food studies, urban studies, social justice, and agricultural studies). Geography appears to be the discipline most engaged in food justice research, publishing 40 articles or 20% of our sample. Sociology journals are also a common site for food justice scholarship, with 11 articles or 5.5% of our sample. Journals in more than a dozen other disciplines have published food justice research, including disciplines as varied as urban planning, anthropology, public health, management, philosophy, and theology.
Overall, 63% of the articles and books in our sample report on original empirical research. Of the 126 empirical works we examined, 38 (or 30.2%) featured one or more organizations as the unit of analysis (see figure 1). Typical organizations studied included activist organizations (advocating for food justice, worker rights, or related issues), urban agriculture organizations, farmers markets, and food banks. Another 27 of the empirical works (or 21.4%) featured entire movements as the unit of analysis, for example using content analysis of social movement framing to assess the potential for food movements in the United States to fundamentally transform the food system (Fairbairn 2012), or analyzing the influence of the global food movement on community food security policies sought by social movements in the United States (Bellows and Hamm 2002). Other common units of analysis included household or individual behaviors related to food acquisition (eight articles or 6.3%); social or educational programs (seven articles or 5.6%); community food access, typically analyzed with spatial techniques (seven articles or 5.6%); academic articles (seven articles or 5.6%); specific policies or planning efforts (six articles or 4.8%); and worker experiences (five articles or 4.0%).
The methodologies employed to study these aspects of food justice were largely qualitative (such as interviews, ethnography and case studies), but varied greatly across the sample. Because many of the scholarly books on food justice are edited volumes with chapters about different research projects, we opted to analyze the research methods only for empirical journal articles (N = 113). Analyzing the methodological choices for edited volumes would have required a different coding strategy, involving a search through individual chapters and separate database notation to indicate methods for each chapter. By far the most common method reported was case-study research: 43 of the articles (38.1%) reported on either single case studies or very small-N comparative case studies (three or fewer cases). Researchers used case studies to answer a wide range of questions about food justice, for instance analyzing the individual and community impacts of social programs ( Other common qualitative methods included interviews (18 articles or 15.9%); participant observation (nine articles or 8.0%); meta-analysis of existing literature (eight articles or 7.1%); ethnography (seven articles or 6.2%); and historical analysis (six articles or 5.3%) 5 . Quantitative methods were less commonly employed, reported in only 22 articles or 19.5% of the sample. Eleven of the articles (9.7%) described conducting surveys of individuals or groups, while another six (5.3%) used GIS, and 5 (4.4%) used statistical methods of content analysis. Additionally, 22 articles (19.5%) reported using multiple methods-typically a combination of interviews and participant observation, or statistical analysis of survey results in combination with another method.
The articles and books which did not report on empirical research were primarily theoretical contributions: situating food justice alongside related concepts such as food security and food sovereignty; elaborating the value of food justice and related concepts to a particular community; encouraging further incorporation of food justice into an academic or professional discipline; contributing to debates within the food justice movement; and/or highlighting new ideas that could be of value to the food justice movement. Of the 74 non-empirical works in our database, about half (32) were focused primarily on social movements. Some of these works described the value of the food justice movement for other practices such as environmental education and social work (Crosley 2014, Kaiser 2011, Conway and Lassiter 2011) or for related movements such as environmental justice (Gottlieb 2009). Others mapped various orientations within the broader food movement 6 to assess persistent tensions and different potentials ( (Guthman 2014, Loo 2014, Gilson 2015, Timmerman and Felix 2015. Other theoretical works synthesized existing research to provide a broad perspective on the social problems related to food justice, untangling their roots in particular political and economic policies (for example Magdoff et al 2000, Albritton 2009, Guthman 2011. Through these theoretical contributions, much has been said about the role of food justice in broader social movements and its relationship to other principles for food system change.

Stability and trends over time
Our analysis of food justice scholarship in the US demonstrates that this body of research is quite diverse, yet has remained relatively stable as it has grown over time. Despite the general stability in research topics however, food justice research appears to be moving 6 The modern food movement encompasses a range of critiques of the food system, as well as calls for (and efforts to implement) alternatives. The concept of 'food justice' overlaps with related goals of 'food security' and 'food sovereignty,' all of which are understood differently in the US and internationally. These distinctions have been thoroughly parsed in earlier scholarship (  away from the study of labor issues (such as the prevalence of low-wage and hazardous jobs in the food system, the labor challenges involved in scaling up alternative food production, and the nature of occupational roles in food justice movements). Additionally, the food justice literature is increasingly concerned with research sites and questions specific to the urban context. We found that food justice scholarship has been generally balanced in its attention to different aspects of the food system, although food processing has received less attention than other areas. In addition to the disciplinary and methodological diversity described above, the field of food justice is diverse in the range of topics it addresses. Food justice research assesses inequalities produced and maintained by the conventional food system, which includes industrial agriculture, food processing, distribution, and consumption practices, each of which can be the locus of research. Food justice research focused on conventional agricultural practices has tended to highlight negative health outcomes (Harrison 2008, Harrison 2011, Holt-Giménez and Patel 2012, Lawrence et al 2013, labor exploitation and farmworker food insecurity (Lo and Jacobson 2011, Wald 2011, Liu and Apollon 2011, Minkoff-Zern 2014a, and policy or technology changes that can improve nutrition and sustainability (Lawrence et al 2013). The bulk of this research draws evidence from grain, fruit, and vegetable agriculture. Conventional animal agriculture is not well represented in the food justice literature, with a few notable exceptions (Gottlieb and Joshi 2010). Similarly, the research investigating justice impacts of food processing systems is fairly sparse. Researchers have noted the low wages and hazards experienced by food processing workers (Lo and Jacobson 2011, Yen Liu and Apollon 2011), and analyzed the effects of food safety policies on local food entrepreneurs' market access (Morales andDay-Farnsworth 2011, Slocum andSaldhana 2016). Food justice research focusing on distribution and/or consumption largely pertains to unequal food access or to alternative food practices, topics to be discussed in more detail below.
Additional entry points for the study of food justice are the social movements seeking to mitigate food system inequalities, policies implemented as a result of food justice advocacy, and the entrepreneurial or social practices developed to offer more equitable alternatives. Because the conventional food system, the food movement, and the alternative food system involve so many actors across a range of sectors and settings, the field of food justice is understandably broad.
For all research, the most common topic addressed was one or more social movements. Social movements were the primary topic of 74 articles and books (see figure 2). These works analyzed food movement goals, framing, and strategies, sometimes contrasting multiple geographically, temporally or conceptually distinct movements or movement organizations. For example, Block et al (2012) compare the trajectories of two social movement organizations using different strategies to improve food access in Chicago. Sbicca (2012) reports on an organization in Oakland which mobilized the local activist base around food justice with broadly resonant framing. In other works, even when social movements were not the primary focus of research, they were often still relevant to the analysis. In total, 137 publications (68.5% of the sample) mentioned social movements or movement organizations as a variable or unit of analysis. The focus on social movements has endured over time, with no statistically significant association between year of pub-lication and incorporation of social movements as a key factor of study.
In addition to social movements, food justice scholarship also examines the development of alternative practices and their social and ecological effects. Alternative practices were the primary focus of 46 publications (23% of the sample) and were noted as an important factor in a total of 108 publications (or 54% of the sample). Food justice research examines alternative entrepreneurial and social practices at all points in the food system. For example, Kremen et al (2012) explain how whole-systems agroecological farming practices help generate ecosystem services as well as social justice benefits, and then outline the socio-institutional conditions that support such farming practices. Brown and Getz (2008) critique the practice of voluntary social-equity certification for California farm products, which they argue fails to adequately represent farm worker interests and relies on neoliberal principles such as privatization and market mechanisms. Goodman et al (2012) introduce the concept of 'reflexive localism' to describe alternative food networks that not only foster local food systems, but also consciously integrate diverse communities into the supply chain, ensuring that people of color and low income people are not marginalized or priced out. Similarly, Vitiello et al (2015) survey food banks nationwide, highlighting innovations such as gleaning, gardening and farming programs that may increase the capacity for low-income communities to meet some of their own food needs. In the same vein, Shamasunder et al (2015) offer a case study of a program in which families in a low-income predominantly Latino neighborhood were given supplies and training to engage in home gardening, finding that the gardens not only increased food access but also community involvement. Galt et al (2014) develop the concept of 'subversive and interstitial food spaces' to describe a range of alternative production and foraging practices, from informal to organized, that challenge or bypass the conventional food system. Works such as these have expanded the field of food justice beyond the study of inequality and social movements, to include critical assessment of practices that diverge from the conventional food system.
One alternative practice has received significant attention in the food justice literature: urban agriculture. Urban agriculture was the primary topic of 21 out of the 46 works focused on alternative practices (46% of the research on alternative practices, and 10.5% of the entire sample). Among all 200 publications, 47 (23.5% of the sample) included urban agriculture as one analytical dimension, if not the primary focus.  (Tornaghi 2014, Walker 2016 or for overlooking race, class and cultural dynamics that tend to limit participation and reinforce existing inequalities (Guthman 2008b, Kato 2013, Hoover 2013, Reynolds 2015. In keeping with its broad scope and interdisciplinary character, food justice research does not often narrow in on specific solutions; even urban agriculture is generally assessed in the context of wider social, political, and economic processes. Indeed, individual food justice studies often assess social movements and alternative practices, since many organizations are involved both in political efforts to highlight and challenge food insecurity and in social or entrepreneurial efforts to implement alternatives. Food justice scholarship appears to focus slightly more on documenting efforts to fight inequality in the food system than on the inequalities themselves, yet unequal food access in particular is still widely discussed. Food access, or the ability of households to obtain healthy, affordable and culturally appropriate food in their communities, was the primary focus of 17 works (8.5% of the sample) and a key element in a total of 74 (37% of the sample). Researchers measured food access spatially, using surveys or GIS techniques to assess entire neighborhoods ( Food justice research also engages with the negative impacts that food access inequalities have on work and health in the US. Health impacts were the primary topic of only two works (1% of the sample), but were included as a key dimension in 27 (13.5% of the sample). For example, Bellows and Hamm (2002) analyze the influence of global food movement discourse on local policy initiatives, emphasizing the impact that policy specifics have on health outcomes and highlighting the importance of structural critique. To this end, other scholars (Albritton 2009, Guthman 2011, Akram-Lodhi 2013) trace the connections between capitalist agri-food systems, hunger, and widespread health problems such as obesity. The relatively low attention to health impacts in the sample surprised the authors, however it is likely an artifact of our sampling strategy rather than evidence of a true lacuna in the literature.
A greater share of the food justice scholarship engages with labor outcomes in the food system. Labor or work was the primary focus of six publications (3% of the sample) and was identified as a key factor in 62 (31% of the sample). Researchers have touted the importance of worker-led movements for justice in the food system (Minkoff-Zern 2014b, Hunt 2015), noted the disproportionate rates of women and peo- The concept of food justice emphasizes how inequalities in the food system are patterned by race, class, and gender, a fact which is borne out in the food justice literature, especially in the attention played to race. While race or ethnicity was the primary focus of only six publications (3% of the sample; see figure 2), race, ethnicity or racism were mentioned as key variables in a total of 104 works (52.5% of the sample; see figure 3). Dozens of the books and articles that focused primarily on a social movement or alternative practice also stressed the role of race and ethnicity in these activities. For instance, researchers have analyzed social movements working to make racial inequalities more visible (Anguelovski 2015, Ramirez 2015, White 2011a) and alternative practices centered on overcoming systematic oppression in the food system (Alkon 2007, White 2011b, Bonacich and Alimahomed-Wilson 2011, Trinidad 2012, Alkon 2012, White 2017). In addition to highlighting efforts to overcome racial inequality, researchers have repeatedly critiqued food movement activists and academics for overlooking the role of exclusionary whiteness within the movement itself (Guthman 2008a, Slocum 2011, Alkon and McCullen 2011, Passidomo 2013, Anguelovski 2015, Ramirez 2015, Bradley and Herrera 2016. To this end, researchers have also documented cases where alternative food initiatives-especially farmers markets and community gardens-have fallen short of achieving social justice goals because of their failure to engage meaningfully with racial inequality and legacies of institutional oppression (Alkon and Mares 2011, Kato 2013, Hoover 2013, Passidomo 2014, Reynolds 2015.
Many food justice scholars are deeply engaged with racial inequality in the food system, and the literature also attends well to class-based inequality. Similar to the pattern for race and ethnicity, many articles and books engaged with class without holding it as the primary focus. In fact, only one article in our sample was primarily focused on class (Alkon et al 2013). However, 68 works (or 34% of the sample) included class and/or income either as a measured variable or primary dimension around which the argument was organized. Scholarship investigating inequalities in food access often notes that the barriers to healthy eating for low-income families (and for communities of color) have more to do with economic and structural factors rather than with knowledge about nutrition (Allen 2004, Kato and McKinney 2015, Krokowski 2016, Lambert-Pennington and Hicks 2016. Other articles document the ways that marginalized classes, such as prisoners and sub-minimum wage food workers, push back against oppressive systems through alternative practices (Sbicca 2016, Hunt 2015. We did not code 'youth' as a specific class, but the food justice literature engages with youth in a similar way. For example, Delgado and Delgado (2016) and Agnelli et al (2016) report on social programs for teens that promote youth empowerment and service through the lens of food justice. Overall, ten articles and books (5% of our sample) included youth as a key factor, with only one focusing on youth as the primary topic. We hope that food justice activists can find more ways to involve youth in their efforts, and that scholars will consider the importance of youth for food-related social movements.
While race and class appear to be widely considered in food justice scholarship, gender-like youthis receiving far less attention. In our sample, only one book was primarily focused on gender (Porter and Redmond 2014) and only 30 works (15% of the sample) included gender as a key factor. Some researchers have noted gender inequalities related to the impacts of food insecurity (Carney 2012) or within the food movement itself, which is largely comprised of women but still tends to promote men to leadership roles (Porter andRedmond 2014, Bradley andHerrera 2016). Other scholars have highlighted the value of feminist methodologies for food justice research (Gilson 2015, Sachs and Patel-Campillo 2014, Alkon 2011.
Two other topics common in food justice literature are policy and land use. Policy (local, state, or national) was the primary topic of ten articles and books (5% of the sample) and was a key factor in a total of 70 (35% of the sample). Most articles examining policy assessed the work of food system planners or food policy councils (Eckert and Shetty 2011, Warshawsky 2010, Scherb et al 2016 or social movement campaigns for worker rights or anti-hunger policies (Brown and Getz 2008, Lo and Jacobson 2011, Hunt 2015, Myers and Sbicca 2015, Shannon 2016. Land use was the primary topic of five publications (2.5% of the sample) and was a key factor in 66 (33% of the sample). Land use is most often the focus of food justice scholarship for its role in global agriculture (Magdoff et al 2000, Bullard 2007, Jarosz 2009, Harrison 2011, Holt-Giménez and Altieri 2013 or the creation of food deserts (Childs and Lewis 2012, Vitiello and Brinkley 2013, Donald 2013, McClintock 2008, and for the study of urban agriculture as a real or potential land use (Kremer and DeLiberty 2011, McClintock 2012, Shamasunder et al 2015, Cohen and Reynolds 2015. The field of food justice has remained relatively stable in its attention to the diverse topics described above; however, the focus on labor and work appears to be decreasing. Logistic regression results indicate that a food justice publication's odds of incorporating labor as a key factor decreased over time. Specifically, each additional year corresponded to a 10.8% decrease in the odds of a food justice publication incorporating labor as a key factor (p = 0.024). Some of the earliest calls to incorporate justice frames into food scholarship and activism stressed the invisibility of food system workers (Allen 2004, Vallianatos et al 2004, Harrison 2008), yet food scholars appear to be turning away from this issue. This finding was surprising, given that popular food writers such as Mark Bittman are increasingly attending to labor in their writings, and because of the increasing visibility of farm and food system worker organizing campaigns such as the Coalition of Immokalee Workers and the Restaurant Opportunity Center (ROC). In addition to the increase in popular attention, two recent scholarly books on farm labor have been well received (Holmes 2013, Gray 2013, the latter of which deals directly with alternative food systems. However, these volumes, as well as two books by ROC founder Saru Jayaraman (2016, 2013), do not use the term 'food justice' (though Jayaraman does discuss food justice in her many public talks).
The field of food justice increasingly focuses on urban rather than rural research sites. Logistic regression results indicate that work focused solely on urban issues is becoming more common. Specifically, each additional year corresponded to a 15.4% increase in purely urban research (p = 0.013). Possible reasons for the increase in urban research might be greater attention to urban food deserts from policymakers and the public in recent years; an increase in innovative socio-entrepreneurial practice in cities; and/or an uptick in social movement mobilization around urban food systems. However, when the binary (purely urban research or not) was expanded to include research that dealt with both rural and urban issues or neither urban nor rural issues, this finding was no longer statistically significant.

Emerging areas
Researchers are beginning to explore the links between food justice and agroecology. A growing interdisciplinary research area, agroecology brings together the physical and social sciences of agriculture, food systems and health in order to promote sustainable practices and transform the food system at multiple scales. Recently, scholars have emphasized the transformative potential of collaboration between agroecologists and food movement activists (Fernandez et al 2013, Holt-Giménez andAltieri 2013). As an interdisciplinary science focused on whole systems, agroecology can incorporate many elements of food justice, including health impacts for workers and consumers, policy analysis, and critical assessments of practices that diverge from the conventional food system. Debate regarding the mechanisms and potential for bringing alternative agricultural practices to scale, prevalent in the agroecology literature (Holt-Giménez 2001, Rosset et al 2011, Altieri and Nicholls 2012, could also inform the food justice literature. Despite some exploration in the context of urban agriculture (McClintock et al 2013, Biewener 2015, food justice scholars have not engaged with the question of scaling up alternative agricultural systems as deeply as those researching food sovereignty and agroecology in the global south. As others have noted, for its part agroecology focuses primarily on ecological goals and does not inherently point toward social goals such as equity and self-determination (Kremen et al 2012, Holt-Giménez andAltieri 2013). Developing a shared language and setting principles for just, sustainable food system transformation is an important step. We believe that increasing collaboration between agroe-cologists and food justice researchers and activists is a natural direction for the field, since both area offer important tools for advancing food systems toward shared goals of sustainability, justice and global health.
Two additional emerging areas are land and immigration. While these areas were not suggested by our data, scholars are currently working on or have recently released books in these areas, and we believe they will be increasingly prominent in the future. With regard to land, Justine M Williams and Eric Holt-Gimenez's recent edited volume Land Justice brings together prominent academics and food justice activists to discuss the essential nature of land in food activism. The authors argue that movements to make food systems more just and sustainable are limited because land remains unaffordable and inaccessible to most people, and they analyze campaigns for land justice based on redistributive policies and cooperative ownership models. Monica White's current project looks at the role that black agrarian programs played in the US civil rights movement and argues that these can serve as a model for contemporary food justice activism (White 2017). Additionally, a number of scholars have current work either recently published or in the pipeline examining the effect of gentrification on urban food justice activism (Glowa 2017, McClintock 2018, Alkon and Cadji 2015, highlighting the ways that the recapitalization of urban space creates opportunities and barriers for food justice organizations. With regard to immigration, Garcia, DuPuis and Mitchell's recently released Food Across Borders (2018), examines the movements of food, and the bodies that produce it, around the world. In this volume, Laura-Anne Minkoff-Zern analyzes the obstacles and opportunities for Latinx farmworkers who have become farm owners, while Teresa Mares describes the social worlds of undocumented dairy workers in Vermont, who are subject to intense scrutiny by the INS because they reside within 100 miles of a national border. Josh Sbicca's forthcoming Food Justice Now will examine, among other things, the relationship between food activists and immigrant rights organizations on the San Diego/Tijuana border. Land and immigration are essential areas to food justice studies and we hope that these recent contributions will inspire further research on these topics.

Conclusion
Like previous reviews of food justice scholarship, our findings confirm that the field of food justice is diverse and highly interdisciplinary, attending to a range of inequalities in both the conventional and alternative food systems, as well as the social movements and alternative practices designed to address them. This broad, synthesizing scope increases the potential value of food justice research and activism to bridge different communities and serve as a conduit to integrate multiple interests (Holt-Giménez and Wang 2011b, Lo and Jacobson 2011, Agyeman 2013, Aftandilian and Dart 2013, Crosley 2014. The field of scholarship has grown substantially since 2011, but has remained relatively stable as it has grown. Researchers have continued to examine the problem of food justice from multiple perspectives, considering how consumers cope with food insecurity as well as how activists and academics make sense of food justice and related concepts. Food justice scholarship continues to look at race, class, and gender inequalities in all aspects of the food systemproduction, distribution, and consumption-as well as the various efforts to reduce them through social movements, state policies, entrepreneurial initiatives, and social practices.
Because this review used an evidence-based methodology, we are able to more closely observe these shifts and provide a more nuanced and specific analysis. Our results differed from previous overviews in a number of ways. We expected a greater proportion of scholarship to focus on inequalities in the conventional food system, in particular public health research related to the health impacts of limited food access. The low representation of such research in our sample likely reflects our sampling strategy rather than a true lacuna in the literature. It seems likely that this literature, while relevant to food justice research, does not use the phrase 'food justice' and so was not counted in our sample. In fact, much of the seminal research analyzing inequalities in the conventional (Goldschmidt 1948, Bell 2004, Buttel et al 1990, Gottlieb and Fisher 1996 and alternative food systems (Allen 2004, Allen et al 2003, Guthman 2004, Slocum 2006, some of which is considered a foundational part of food justice research, predated the use of the term 'food justice' and contributed to the emergence of food justice activism. Still, the low representation of empirical research documenting food inequalities points to a need for greater cross-disciplinary communication, and further connection between public health scholars and food justice activists. The limitations of the search term 'food justice' are important because they also suggest future directions for scholarship. As the discourse grows, the term may be increasingly recognized by scholars working on related issues in both the natural and social sciences-issues such as water, teleconnections and the economics of food security. Awareness of the food justice literature may prompt scholars in these areas to engage with it, and to better attend to the ways that inequalities affect the questions they ask and the data they analyze.
The apparent shift away from researching labor and work is concerning, since workers all along the food supply chain continue to suffer exploitation. Indeed, it is somewhat ironic that food justice research is moving away from this issue just as activist groups such as the Restaurant Opportunity Center and the Coalition of Immokalee Workers have put food at the center of a reinvigorated labor movement, and food writers such as Mark Bittman and Eric Schlosser have increasingly recognized their efforts as a part of the food movement. Additionally, many food workers, especially undocumented immigrant workers, are potentially more marginalized in the Trump era than they were previously. Food justice researchers should continue to examine questions of worker exploitation, inequalities of race, class and gender in food system employment, and the ways that the food movement is or is not attending to labor injustices. Research should also attend to the fledgling alliances being developed between the food justice, immigrant rights and labor movements.
Our findings also highlight the prevalence of case study research in food justice scholarship. Considering the rich knowledge of practices, processes and perspectives that this inductive research has developed, we encourage researchers to continue building on this knowledge through deductive methods and participatory research. Scholars can aid the food justice cause by identifying the most effective social movement strategies and alternative social or entrepreneurial practices for different contexts. As others have suggested (Wakefield 2007, Campbell et al 2013, public scholarship that bridges academia and practice/activism may have the greatest impact-especially in the areas of agroecology, social entrepreneurship, and social movements. We also believe the field is ripe for more multi-case research, including qualitative comparisons of several similar cases and quantitative studies of larger samples. One area that we believe has reached saturation is work parsing the transformative potential of particular programs, strategies and organizations. Case studies continue to be essential to food justice research, but we hope that future scholarship can move beyond the practical work of evaluating these alternatives and toward more finely-grained analytic questions. We would particularly like to see qualitative work examining how participating food justice alternatives and/or activism shapes one's sense of self or a community's understanding of its own well-being. Food justice research can also pay greater attention to how communities regard their own food histories and foodways, and how these traditions can fuel social movement work (for example Pena et al 2017). Quantitative work can also be useful in developing larger-scale cross-case comparisons of organizational strategies.
As a final note, while it is important to analyze the movements and practices that are working toward food justice, it is also important to continue documenting inequalities in the food system and their negative impacts to society as a whole. Researchers in the field of food justice seem to favor studying the activists with whom we sympathize and are often allied. However, it is important to also better understand the structural factors that produce the food injustices these activists work to ameliorate. Such research may be particularly useful to activists in that it can guide them toward adopting effective strategies. Moreover, such research is critical for motivating policymakers and the public toward food system transformation.

References
Aftandilian D and Dart L 2013 Using garden-based service-learning to work toward food justice, better educate students, and strengthen campus-community ties J.