Vanessa Peña-Garcia, Matthias Ojo, Sherin Lajevardi, Ethan Lawrence, Naima Batson, Selom Stacey Gbewonyo, Esinam Attipoe, Darrin S. Ward, Denise Willoughby, Eric Gomez

About the Community

Los Angeles is an economically diverse city where extreme wealth and financial hardship coexist. Los Angeles County is divided into eight service planning areas (SPAs), which are geographic regions that are used for healthcare planning and resource distribution. Due to years of systemic racism and resource misallocation, significant inequities exist across the various SPAs. South Los Angeles, specifically service planning area 6 (SPA-6), is home to predominantly Black and Latinx communities and has been marginalized and historically disinvested in, facing significant health inequities.

Data from the 2017 LA County Key Indicators of Health Report showed concerning trends in SPA-6, including the second-highest rate of food insecurity among low-income households participating in the Supplemental Nutrition Assistance Program (SNAP), the highest prevalence of daily soda consumption among adults, the lowest consumption of fruits and vegetables, and the highest percentage of adults at risk for major depression within LA County.

These findings may suggest a potential relationship between dietary practices and mental health in this community. One mechanism by which diet is linked with mental health is through the gut-brain axis. For example, research suggests a healthy gut microbiome, cultivated through a balanced diet, is linked to a positive mental well-being and robust immune system (Appleton, 2018). Part of our immune system resides in the gut, and inflammation due to an unhealthy diet can lead to a disruption and imbalance of our normal, healthy bacteria, which studies have shown to be associated with mental health disorders (Clapp, 2017). However, the biological mechanism of the gut-brain axis happens in a broader context, with social, political, and economic factors shaping people’s diets.

Currently, food systems in the United States fail to provide equitable access to healthy food across all communities. This systemic inequity disproportionately affects low-income and often overlooked neighborhoods like SPA-6. SPA-6 residents face a food swamp environment, an area with an abundance of unhealthy fast-food outlets and convenience stores, and food deserts, which have limited access to supermarkets and fresh produce vendors. This lack of access to healthy food, coupled with social determinants of health (SDOH) like racism, poverty, and redlining, has historically produced segregated communities, making it difficult to increase healthy food options for residents (Smith et al., 2021).

The goal of our project was to explore, through interviewing diverse community representatives, the multiple factors influencing the relationship between food and mental health. As medical students, we were also interested in the role of the gut-brain axis, given our biomedical training; however, based on our lived experiences and commitment to address the social determinants of health, our guiding framework is the biopsychosocial model. The gut-brain axis is defined as the two-way, complex connection between gut bacteria and the brain that is vital for the homeostasis of the gastrointestinal and central nervous systems through biological networks of chemical transmitters and neuronal pathways (Morais, Schreiber IV, & Mazmanian, 2021). There is a significant relationship between food insecurity, malnutrition, and imbalance of the gut microbiome, which is associated with negative impacts on the gut-brain axis and thereby our mental health (Christian, 2020).

As future physicians committed to health equity, we wanted to explore the connection between biological processes, such as the gut-brain axis and mental health, in the context of our local communities and the inequities they face. Therefore, we applied the biopsychosocial model (Papadimitriou, 2017) to guide our approach, allowing us to explore the connections among biological processes, psychological health, and social determinants of health, such as access to healthy food. Figure 1 below illustrates a social ecological model, including the components of the biopsychosocial framework, with individual biology/gut-microbiome and mental health interconnected with multiple community and structural systems. This model highlights the micro and macro-level factors in the ecology of food and mental health (i.e., depression), resonating with the ecological model of community psychology.

The project focused on adults (ages 18-45) in SPA-6, in recognition of the need for further research on the impact of food insecurity on their mental health. At the root of food insecurity is often the inability to access healthy foods. “Food swamps” are defined as neighborhoods with a prevalence of unhealthy food establishments selling ultra-processed foods, compared to food establishments with healthier choices, including grocery stores with fresh produce (De França et al., 2024). South LA’s food swamp environment is a potential risk factor for negative mental health, such as depression.

Biological Level

Current scientific literature suggests psychological and physiological connections to the food we eat and the biological foundations of the gut-brain axis (Berding et al., 2020; Doenyas et al., 2025; Patil & Mehdi, 2025). Unhealthy eating habits have direct negative consequences, affecting the gut microbiome, our stomach and natural intestinal environment, consisting of a delicate balance between different types of bacteria, and potentially leading to other chronic diseases that may further deteriorate mental health (Vijay & Valdes, 2022). On the other hand, sustaining a healthy diet can do the opposite – stimulating several physiological and immunological mechanisms linked to increasing positive mental well-being.

Psychological Level

Ultimately, the complex relationship between biological mechanisms and diet goes beyond individual health choices. For example, the stress of living in a food desert, an area with a lack of access to fresh and healthy foods, struggling to obtain healthy food for oneself and one’s family, can negatively impact mental health. This stress can also lead to a variety of unhealthy coping mechanisms, such as relying on fast and available, processed foods, which exacerbate the existing biological and psychological problems – creating a vicious cycle of stress, unhealthy food choices, an imbalanced gut microbiome, and negative mental health outcomes. Mental health is often influenced by numerous factors, including diet, access to healthcare, and environmental stressors. Recent research efforts have suggested that the gut-brain axis dysfunction may be involved in the pathophysiology of several mental health disorders, such as depression, anxiety, schizophrenia, addiction, neurodegenerative diseases, as well as age-related cognitive decline (Rogers et al., 2016; Sherwin et al., 2018). By recognizing that mental health cannot be separated from physical health, and viewing health through the lens of a biopsychosocial model, we can develop a more holistic approach to the prevention and treatment of mental health.

Social Level

In addition to the biological and psychological levels of the biopsychosocial model, we must address the social level of the model and address the challenges of accessing not just healthy food but mental health services in South LA. Limited services, especially culturally responsive services, a lack of understanding about mental health, and stigma surrounding mental health create significant barriers for individuals seeking and accessing support. Research shows concerning inequities in mental health access for Black and Latinx communities, highlighting the need for culturally and community-responsive interventions (Alegría, Alvarez, Ishikawa, DiMarzio, & McPeck, 2016). Our project seeks to illuminate the impact of the flawed food system on mental health in South LA.

How We Came to Work with this Community

As current medical students at Charles R. Drew University of Medicine and Science (CDU) located in South LA, some of us grew up in South LA, have family in the area, or grew up with lived experiences very similar to the neighborhoods in South LA. Our experiences with inequities further drive us to serve and address gaps impacting the communities in South LA. For example, one of our group members’ experiences with health inequities like the ones the community of South LA faces, motivates them to practice as a physician in these communities. Due to growing up without medical insurance, they remember having to wait long hours at their local community clinic, along with what felt like ‘the entire city’ because of the high volume of clients frequenting the clinic. Experiencing a lack of access to medical care, financial hardship, and knowing that many other members of their community face the same struggles, they are motivated to address these societal issues as future physicians.

Project Description

Our project is part of a larger medicine and society course that focuses on the social issues and inequities in medicine.  Our team was composed of ten medical students, who combined their passion for nutrition, cooking, mental health, research, and commitment to health equity with our communities, to engage diverse local representatives in learning more about the biopsychosocial factors influencing the relationship between healthy food access and mental health.

Methodology

To capture a variety of perspectives within the communities of SPA-6, we interviewed the following categories of community representatives:

(1) patients, family members, and community-based organizations/advocates,

(2) healthcare providers and team members, and

(3) government officials, researchers, and policy experts.

Subsequently, this led to discussions on what organizations and/or individuals would best represent our topic and the communities of SPA-6. The community representatives included:

(a) a staff member from the Community Healing Center of the Los Angeles County Department of Public Health,

(b) a staff member from the Compton Community Garden,

(c) a university professor and community advocate,

(d) a manager from a community-based farmers market,

(e) a community member with a history of depression,

(f) a family medicine physician,

(g) a psychiatrist,

(h) a nutritionist,

(i) a government representative at CalFresh- California’s Supplemental Nutrition Assistance Program,

(j) a California State Assembly representative, and

(k) a gut microbiome researcher.

Our questions addressed the following key areas:

1. Perspectives or experiences with inequities in healthy food access and mental health,

2. Awareness or experiences with policies or interventions addressing healthy food access and mental health, and

3. Perspectives or experiences with solutions to inequities in healthy food access and mental health.

Additionally, we structured our questions to be relevant to the specific interviewee – community member, community advocate, policy maker, researcher, or healthcare professional. After conducting all interviews, we met as a team to analyze the transcripts of the interviews for key themes.

Community Needs

Access to healthy food options in South LA is hindered by large “food deserts,” in which there is a significant lack of access to fresh, nutritious foods. Lack of access, on the other hand, can contribute notably to poor general well-being of the community, due to stress, anxiety, or depression. Furthermore, limited access to mental health resources in communities such as SPA-6 adds even more to the problem.

This factor further crystallized the urgency to bridge the gap between healthy food access and mental well-being. As future physicians, we are conscious of how health care providers have a significant role and responsibility to advocate for policies and programs that assure better access to healthy foods and mental health for particularly under-resourced communities, such as in South LA. Addressing community needs in South LA goes beyond increased food access. Increased funding of culturally responsive mental health services and embedding them within existing primary care clinics may decrease the stigma and barriers to patients seeking and obtaining mental health support.

In other words, what is needed is collaboration between health professional groups, community organizations, and policymakers. Such interdisciplinary teams to help find solutions to this issue and provide healthy meals could include Chefs to End Hunger and programs offered through food reclamation under Senate Bill 1383. California Senate Bill 1383 is a climate law increasing statewide organic waste recycling and mandating businesses to donate surplus food instead of tossing it (Harrison et al., 2024). It is through such investments that communities experiencing food deserts will be in a better position to collaborate with health systems and organizations to address these complex needs.

Community Representatives

With support from our course faculty and their networks, we were able to connect with and interview eight [I count 10] community representatives. The community representatives included an NIH researcher, a psychiatrist, a family medicine physician, a dietician, a non-profit organization building sustainable food systems, a community garden representative, a community healing center, an LA County Department of Public Health representative, a California state assembly representative, and a patient who previously received mental health services.

Learning from Community Representatives – Outcomes and Impact

Our thematic analyses of the diverse interviews yielded the following three key themes and associated subthemes:

(1) Food access and security (challenges and approaches to improvement)

The theme of food access and security is highlighted by the area of SPA-6, qualifying as a food desert, lacking readily available fresh produce options.

(2) The impact of food on health (community context and gut-brain axis)

The theme of food’s impact on health is explored through the discussion of community context and the gut-brain axis.

(3) Social determinants of health (structural racism and policy decision-making)

The theme of social determinants of health is related to the first two themes and also highlights the challenges of structural racism and policy decision-making.

Theme 1: Food Access and Security – Challenges and Approaches to Improvement

Challenges: A significant portion of our immune system resides in our gut-microbiome, and inflammation there can lead to an increase of pro-inflammatory cytokines, triggering an immune system response, which has been associated with mental health disorders (Clapp M, 2017).

“Addictions, depression, mental health disorders are serious but treatable conditions, but treatable means having access to treatment”, said the NIH researcher.

As the quote suggests, mental health conditions are treatable, but access to treatment is a significant barrier, especially for under-resourced communities.

“In underserved populations, we know that access to treatment on its own is very challenging. So it really becomes a catch-22 because you can be in an environment that is already exposing you more to that”.This quote highlights the “catch-22” faced by these populations: limited access to mental health treatment coexists with environmental factors that increase the risk of mental health disorders. The NIH researcher emphasizes the first theme of food access and security through the challenges faced by underresourced communities in accessing treatment for mental health challenges. These challenges can then be exacerbated by the negative societal conditions already faced, such as limited healthy food options, creating a vicious cycle of lack of access and depression.

Our research aimed to capture the patient’s perspective for insights into SPA-6 community health experiences. We interviewed a local resident who had completed a two-month therapy program following an assessment for Adverse Childhood Experiences (ACES). The patient emphasized how their neighborhood was considered a food desert, discussing the impact of fast-food availability versus grocery stores and the reliance on liquor stores for essentials. Although research shows a correlation between food insecurity and depression — with greater insecurity correlating with a higher likelihood of depression (Reeder et al., 2021) — the interviewed patient did not perceive a personal connection between their mental health and their dietary choices. However, the patient recognized how unhealthy food options contribute to higher health costs:

“A lot of our community members rely on little markets… It’s a reason why we don’t have grocery stores. It contributes to paying higher medical bills.”

This interview emphasizes the theme of challenges with food access and security through discussing the prevalence of fast food and liquor stores over grocery stores.

Approaches to Improvement: Many of the barriers to connecting the community to these resources are partly due to the bureaucracy of either applying to federal financial support programs, like CalFresh, or signing up to be a vendor at the local Farmers’ Markets. Their efforts have helped to alleviate much of this burden by aiding both parties with their respective applications. Additionally, Food Access LA has been working with the community by offering healthy cooking classes and delivery to community members who are physically unable to make it to the market, highlighting the theme of food access and security.

Collaborating with the Department of Public Social Services (DPSS) revealed the importance of community collaboration in tackling issues like food insecurity. The work DPSS does with its partner organizations demonstrates that addressing social challenges requires not just government efforts, but a broad, community-engaged approach that includes local agencies, educational institutions, and community organizations. DPSS has implemented collaborations with over 300 community-based organizations, colleges, food banks, and homeless shelters to further improve access and ensure that people in need are connected to the resources available to them. By working together, these groups create a network of support that ensures that vulnerable populations—such as low-income families, students, and the unhoused—can access resources like food assistance, underscoring the theme of food access and security as well.

Theme 2: The Impact of Food on Health – Community Context and Gut-Brain Axis

Community Context: The CDU professor spoke about her current battle against food insecurity in SPA-6 by partnering with local churches. She strives to make food access more participant-driven through the creation of community gardens where residents can grow produce for themselves, thus combating the food desert that many residents in SPA-6 experience. She explains:

“Community gardens empower the community; they let them know that they can make a difference in terms of the health challenges they face. Communities that are medically underserved and face barriers to them living healthy lives, like structural racism.”

Further reiterating,

“If you don’t have access to good foods to improve your diet, your health won’t improve. Lots of grocery store vegetables have mold on them in these communities: how can you change your life and alter health outcomes if you don’t have choices to what’s available to you?”

The interview with the CDU professor emphasizes the impact of activism at the grassroots level on community health. She also recognizes the detrimental impact of certain foods on illnesses that disproportionately impact SPA-6 residents. The interview indirectly highlighted the gut-brain axis by discussing the critical need for nutrient-dense food to improve mental health and overall well-being through empowering local communities with food education and improved access.

Gut-Brain Axis: In addition, through an interview with a nutritionist, we gained further insight into the connection between the gut-brain axis and the state of food insecurity in communities like South LA. They highlighted the physiological and psychological effects of food insecurity, specifically how such factors lead to the development of chronic diseases such as reactive hypoglycemia, iron deficiency anemia, leptin resistance, obesity, and renal failure. Furthermore, they explained that over time, patients with such chronic diseases develop inflammatory states that have been linked to the development of mood disorders such as depression.

This interview also underscored the effects of processed foods on mental health. They pointed out,

“Many processed foods have inflammatory effects on the body. Processed foods often contain high levels of sugar, unhealthy fats, and salt, but also lack essential nutrients like vitamins, minerals, and fiber, which can lead to mood disorders and depression.”

They further explained,

“Consuming a diet high in processed foods can also disrupt the balance of gut microbiota, leading to inflammation and changes in neurotransmitter levels, which are associated with mood disorders.”

Overall, the interview further shed light on the complexity of the gut-brain axis and how its disruption can have significant consequences on a physiological, but also psychological level, highlighting the theme of the impact of food on health.

Theme 3: Social Determinants of Health – Addressing Structural Racism and Policy Decision-Making

Addressing Structural Racism: Gaining insights from a psychiatrist specializing in trauma gave us critical insights into the indirect role of food insecurity on mental health, specifically in Black and Brown populations. They emphasized that:

“It’s really about the whole food versus the processed foods, and unfortunately, a lot of foods in the [U.S.] that are accessible, especially in communities that don’t have a lot of resources, are processed foods”.

They ended the interview by stressing the importance of food education, access to healthy options through farmers’ markets/food pantries, and combating structural racism in food systems, underscoring all three key themes and especially the root problem of structural racism.

In addition to grassroots efforts to tackle inequities in healthy food access, improving healthy food access and mental health necessitate addressing entrenched issues such as structural racism and redlining that have impacted marginalized communities for generations. The director of the Los Angeles County Department of Public Health emphasized that without significant strides in poverty alleviation, progress in combating food insecurity will remain limited. Creating public-private partnerships to increase access to healthy foods in underserved areas is essential to improving environmental justice, reducing neighborhood inequities, promoting healthy eating habits, and providing better healthcare (Hilmers et al., 2012). As was stated, we must continue,

“lifting community voices, supporting communities, having programs that come out of cities, counties that really have an equity lens, which is addressed to providing additional resources for communities that need them to help improve healthy food access”.

Policy Decision-Making: Insights from the representative of the California State Assembly showed that,

“big grocers do not want to invest in the area because of its financial liability.”

They mentioned,

“the cost to protect against crime and vandalism is not worth the investment.”

Moreover, their main agenda is gun control, impacting the attention needed to more directly address the issue of accessing healthy foods. At the same time, he understands the need for change in nutrition and food deserts. They focus on getting ghost guns off the street and making their district safer for constituents, highlighting the complexity of the theme of social determinants of health, particularly how other competing social priorities, such as gun violence, can influence decision-making around policy actions addressing food and health issues.

Regarding healthcare professionals’ role in addressing food-related health inequities, the healthcare provider we interviewed emphasized the importance of community engagement, advocacy, and research. They underscored the significance of understanding community needs and involving stakeholders in decision-making processes to enact effective policies and interventions. There is a need for a multi-level approach involving decision-making by healthcare providers, community organizations, policymakers, and researchers to tackle food access inequities and promote better gastrointestinal health and overall well-being in under-resourced communities like SPA-6. Initiatives such as community gardens and educational programs can empower individuals and families to take actions to solve the community inequities affecting healthy food access.

Lessons Learned

The following are some main lessons learned:

• Addressing structural racism through collaborating with community stakeholders that specialize in different areas is a holistic approach to making a societal impact on under-resourced communities.
• An additional avenue to addressing food insecurity in South Los Angeles from a more macro level is to integrate nutritional education from an ecological lens and its relationship to mental health in the medical education of students.
• Patients and community residents should have access to education on how food and nutritional inequities affect mental health, particularly regarding the gut-brain axis, highlighting the detrimental impact of unhealthy/ultra-processed food on mental health.
• Enhancing awareness about community-based resources, such as community gardens, or farmer’s markets, or other ways to tackle systemic barriers to accessing healthy foods.
• There are significant challenges involved in organizing and sustaining a farmers’ market, including finding vendors, establishing vendors, and creating affordable prices.
• To create effective solutions, it is crucial to involve the community and leverage local knowledge and resources.
• As we reflect on the challenges people face in accessing necessities like food, we realize how critical it is for physicians to advocate for their patients beyond the clinical setting.
• Change needs to occur at the policy level to make a difference in the community, enhancing the medical perspective when decisions about patients are being made in ways that are grounded in the community.

Looking Forward

Looking forward, addressing mental health in communities like SPA-6, one that is considered both a food swamp and a food desert, will require leveraging community resources. Community leaders, those who oversee making key decisions for community members, must hold a space where all can convene and bring all aspects of the biopsychosocial model of mental health together. Leveraging health counselors and community health workers who come from the community and can connect community members with various resources is one way to provide culturally relevant support and facilitate access to healthy food choices and mental health services.

In a study focused on addressing food insecurity in low-income adults with hypertension using a community health worker-delivered nutrition intervention, patients responded favorably to simplified nutrition guidance and educational materials using traffic light nutrition ranking where food is categorized into 3 color-coded categories: most healthy (green), medium healthy (yellow), or least healthy (red) food items based on national guidelines (Rivera et al., 2019; Gu et al., 2024). Similarly, one solution to addressing food insecurity and mental health is to provide nutritional education provided by community members who understand the context of their community.

Ultra-processed foods that are industrially processed and often pre-packaged, convenient, energy-dense, and nutrient-poor contribute to non-communicable diseases such as diabetes and cardiovascular disease and induce changes in the gut microbiome (Brichacek et al. 2024). At the macro level, policymakers need to revise dietary guidelines to limit ultra-processed foods and emphasize a wider variety of gut-friendly options. One way to increase access to gut-friendly foods is to encourage policymakers to ensure that grocery stores known to promote more of these foods are intentionally placed in areas with the highest need for them, including SPA-6. This could help foster food policies that prioritize the health of vulnerable populations and can ultimately lead to improved mental health outcomes related to nutrition and diet. Furthermore, increasing research funding for microbiome-based interventions is vital for increasing our knowledge of the extent to which gut health impacts mental health. Microbiome-based interventions that inform dietary strategies can transform the landscape of mental health care for food-insecure populations.

Finally, we should continue to honor the life-long work of scholars and community participants who emphasize the importance of investigating systemic injustices present in our food systems across the United States. This work highlights the critical need to understand the intersectionality of socioeconomic status, race, and geographic location to develop comprehensive interventions that specifically target the root of food insecurity and, ultimately, negative mental health outcomes. In a systematic review of 39 trials of evidence-based mental health interventions for under-resourced communities, the majority of trials found that community health worker-delivered interventions reduced symptoms of depression by outreaching to facilitate entry into provider settings, providing auxiliary support through case management and promoting patient adherence, and providing lower levels of care to patients with less intensive needs (Barnett et al., 2018). Addressing the mental health component of the biopsychosocial model using community health workers is one way to address the comprehensive needs of individuals in SPA-6 and beyond. Further research should continue to explore barriers to health, which often include political and systemic aspects of health. By shedding light on multiple complexities, we can create and advocate for specialized policies that create healthier communities by alleviating food insecurity and promoting equity in mental health care.

Relevance to Community Psychology

Community psychology focuses on how individual well-being is shaped by social, economic, cultural, political, and environmental influences within communities. This research project allowed us to see the individual, community, and structural factors that influence the relationship of food and mental health in the South Los Angeles community. The Ecology of Food and Mental Health model illustrated in Figure 1 aligns with community’s psychology’s holistic approach to health. Diet influences mental health through the gut-brain axis which is closely linked with stress, depression, and anxiety. Social determinants of health, including systemic barriers such as poverty and food deserts, compound biological and psychological factors. Community psychology’s emphasis on community-driven solutions and advocacy are essential in addressing the complexities of the interactions between food insecurity, the gut-brain axis, and mental health.

On an individual level, access to healthy foods often begins with the ability to afford healthy meals. According to the U.S. Department of Agriculture’s Food and Nutrition Service, 18 percent of people who are eligible for the Supplemental Nutrition Assistance Program are not participating (2018). One tangible way to be involved in the community is to partner with community-based organizations to support individuals with the CalFresh benefits application process. By partnering with grassroots efforts that see the needs of the community on a day-to-day basis, we can better understand the advocacy necessary at the neighborhood level, reflecting the community psychology goal of implementing and supporting policies that address individual and systemic challenges. Community gardens and farmer’s markets are offering avenues for increased access to fresh and healthy produce. They are also empowering communities and individuals as seen by (Weight, 2023) students at California State University San Marcos, who after attending a course on food inequalities became more comfortable utilizing CalFresh services and the on campus food pantry, and providing culturally relevant foods, indirectly tackling macro-level forces of unjust food systems (Weight, 2023)

Overall, we need to enhance the collaboration amongst community members, physicians, community-based organizations, government agencies and healthcare systems to improve food security and access to healthy foods in under resourced communities. In addition, challenging traditional medical education to be more inclusive of the ecological contexts of community psychology would allow for a more multi-level holistic view of nutrition and mental health. Systemic change necessitates collaboration among different levels of community representatives and community residents to better understand the biological, psychological, and social factors shaping the access of healthy foods and mental well-being support.

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