Food and Nutrition Insecurity: Experiences That Differ for Some and Independently Predict Diet-Related Disease, Los Angeles County, 2022.

BACKGROUND: National surveillance shows that food insecurity affects ∼1 in 10 Americans each year. Recently, experts have advocated for surveillance of nutrition insecurity alongside food insecurity. Nutrition security refers to the nutritional adequacy of accessible food and factors that impact one's ability to meet food preferences. OBJECTIVES: This study presents representative estimates of food insecurity and nutrition insecurity for Los Angeles County, CA, United States; compares predictors of these constructs; and examines whether they independently predict diet-related health outcomes. METHODS: In December 2022, a representative sample of Los Angeles County adults participating in the Understanding America Study (N = 1071) was surveyed about household food insecurity and nutrition insecurity over the past 12 months. Data were analyzed in 2023. RESULTS: Reported rates were similar for food insecurity (24%) and nutrition insecurity (25%), but the overlap of these subgroups was less than 60%. Logistic regression models indicated that non-Hispanic Asian individuals had higher odds of nutrition insecurity but not food insecurity. Moreover, nutrition insecurity was a stronger predictor of diabetes compared with food insecurity, and both constructs independently predicted poor mental health. CONCLUSIONS: Food and nutrition insecurity affect somewhat different populations. Both constructs are valuable predictors of diet-related health outcomes. Monitoring nutrition insecurity in addition to food insecurity can provide new information about populations with barriers to healthy diets.

Vulnerability or Resiliency? A Two-Wave Panel Analysis of Social Network Factors Associated with Glycemic Levels among Mexican Immigrants in the Bronx, NYC, Before and During COVID-19.

Latinos have high rates of type 2 diabetes mellitus (T2DM) yet are characterized as having health-promoting social networks. The impacts of COVID-19 on personal networks were complex, especially in urban areas with high proportion of immigrants such as the Bronx in NYC. Our objective was to test the extent to which network characteristics increase vulnerability or resiliency for glycemic control based on data gathered from Mexican-origin Bronx dwellers. We used two-wave panel study analyzing self-reported personal social networks (n=30participants; 600network members) and HbA1c levels via dried blood spots in 2019, before the COVID-19 pandemic, and in 2021, a time after initial lockdowns and when the pandemic was still ravaging the community of study. Regression models adjusted for individual-level variables including sociodemographic and health indicators (i.e., physical health including COVID-19 and mental health). We found that an increase in the proportion of network members with diabetes predicted an increase in participant's HbA1c levels from 2019 to 2021 (ß=0.044, p < 0.05). Also, a greater proportion of network members consuming "an American diet" in 2019 predicted a decrease in participant's HbA1c levels (ß=-0.028, p < 0.01), while a greater proportion of network members that encouraged participants' health in 2019 predicted an increase in participant's HbA1c levels (ß=0.033, p < 0.05). Our study sheds light on specific social network characteristics relevant to individual diabetes outcomes, including potential longitudinal mechanistic effects that played out at the peak of the COVID-19 crisis.

Socio-ecological factors linked with changes in adults' dietary intake in Los Angeles County during the peak of the coronavirus 2019 pandemic.

OBJECTIVE: Comprehensive studies examining longitudinal predictors of dietary change during the coronavirus disease 2019 pandemic are lacking. Based on an ecological framework, this study used longitudinal data to test if individual, social and environmental factors predicted change in dietary intake during the peak of the coronavirus 2019 pandemic in Los Angeles County and examined interactions among the multilevel predictors. DESIGN: We analysed two survey waves (e.g. baseline and follow-up) of the Understanding America Study, administered online to the same participants 3 months apart. The surveys assessed dietary intake and individual, social, and neighbourhood factors potentially associated with diet. Lagged multilevel regression models were used to predict change from baseline to follow-up in daily servings of fruits, vegetables and sugar-sweetened beverages. SETTING: Data were collected in October 2020 and January 2021, during the peak of the coronavirus disease 2019 pandemic in Los Angeles County. PARTICIPANTS: 903 adults representative of Los Angeles County households. RESULTS: Individuals who had depression and less education or who identified as non-Hispanic Black or Hispanic reported unhealthy dietary changes over the study period. Individuals with smaller social networks, especially low-income individuals with smaller networks, also reported unhealthy dietary changes. After accounting for individual and social factors, neighbourhood factors were generally not associated with dietary change. CONCLUSIONS: Given poor diets are a leading cause of death in the USA, addressing ecological risk factors that put some segments of the community at risk for unhealthy dietary changes during a crisis should be a priority for health interventions and policy.

Understanding food insecurity in Los Angeles County during the COVID-19 pandemic and its aftermath: A qualitative interview study.

The COVID-19 pandemic brought increases in food insecurity in Los Angeles (L.A.) County, defined as lacking household access to adequate food because of limited money or other resources. Here, we aimed to understand the lived experiences of food insecurity during the COVID-19 pandemic and its aftermath. In August-December 2022, we interviewed 30 residents of L.A. County who were participants in an ongoing internet panel and had reported experiencing food insecurity between April 2020 and July 2021. A stratified-sampling approach was used to recruit a diverse sample with and without government food assistance. We report five key findings, which underscore the stress and worry associated with the experience of food insecurity, and the coping strategies people implemented: (1) The pandemic prompted food insecurity as well as stressful shifts in eating behaviors compared to before the pandemic, with some eating much less food, some eating less nutritious food, and some eating much more due to being stuck at home; (2) Buying food became more effortful and financially challenging; (3) Government food assistance from the Supplemental Nutrition Assistance Program (SNAP) was important for reducing food insecurity, but was sometimes insufficient, inconsistent, and didn't cover all retailers or food items; (4) Interviewees had to rely on their social networks, food banks or pantries, churches, and schools to meet their food needs and cope with food insecurity, but some faced barriers in doing so; (5) For some, food insecurity was worse in late 2022, almost two years after the pandemic started. We conclude with implications for policymakers and practitioners, emphasizing the importance of meeting the needs of diverse residents and addressing food insecurity in the aftermath of the COVID-19 pandemic.

Ecological risk and protective factors for food insufficiency in Los Angeles County during the COVID-19 pandemic.

OBJECTIVE: The COVID-19 pandemic increased food insufficiency: a severe form of food insecurity. Drawing on an ecological framework, we aimed to understand factors that contributed to changes in food insufficiency from April to December 2020, in a large urban population hard hit by the pandemic. DESIGN: We conducted internet surveys every 2 weeks in April-December 2020, including a subset of items from the Food Insecurity Experience Scale. Longitudinal analysis identified predictors of food insufficiency, using fixed effects models. SETTING: Los Angeles County, which has a diverse population of 10 million residents. PARTICIPANTS: A representative sample of 1535 adults in Los Angeles County who are participants in the Understanding Coronavirus in America tracking survey. RESULTS: Rates of food insufficiency spiked in the first year of the pandemic, especially among participants living in poverty, in middle adulthood and with larger households. Government food assistance from the Supplemental Nutrition Assistance Program was significantly associated with reduced food insufficiency over time, while other forms of assistance such as help from family and friends or stimulus funds were not. CONCLUSIONS: The findings highlight that during a crisis, there is value in rapidly monitoring food insufficiency and investing in government food benefits.

Nosotros mismos nos estamos matando/We are the ones killing ourselves: Unraveling individual and network characteristics associated with negative dietary acculturation among Mexican Americans in New York City.

BACKGROUND: Research on negative dietary acculturation among Mexican-Americans has mostly focused on individual-level processes and has largely ignored the role of social networks. METHODS: This mixed-method study used an egocentric network approach and derived 1620 personal ties of self-identified Mexican adults in New York. 24-hour dietary recalls were used to derive a total Healthy Eating Index (HEI) and subscores. The qualitative portion generated narratives around who helps or hinders their efforts to eat healthfully. RESULTS: At the individual level, age at which participants migrated to the U.S. was negatively associated with total HEI (ß = -0.39, p < .01). An annual income below $30,000 was positively associated with total HEI (ß = 0.25, p < .05) and with HEI fruit subscores (ß = 0.25, p < .05). Acculturative stress was negatively associated with HEI fruit (ß = -0.29, p < .05) and refined grain subscores (ß = -0.34, p < .01). At the network level, the proportion of network members who consumed traditional Latino diets was negatively associated with total HEI and HEI refined grains subscores (ß = -0.39, p < .001; and ß = -0.23, p < .05; respectively). In contrast, the proportion of alters who lived in another country was positively associated with HEI dairy subscores (ß = 0.25, p < .05). Juxtaposing qualitative participants' visual representation of their total HEI scores with their lay interpretations of healthy and unhealthy eating matched public health messages of reducing sugar, red meat intake, and processed foods. However, participants felt that this could only be achieved through restriction rather than balance. Qualitative narratives also elucidated how dietary acculturation and income could help shape dietary quality in unexpected ways. CONCLUSIONS: This study found evidence of negative dietary acculturation and showcases the complex ways in which both individual- and network-level processes help shape dietary choices for Mexican-Americans.

Examining food intake similarities in adolescent best friend dyads using longitudinal Actor-Partner Interdependence Models.

Little is known about how adolescent best friends may affect each other's food intake. This study explored whether friendship selection and socialization mechanisms explained potential food intake similarities in adolescent reciprocated best friend dyads. We also tested whether socialization processes were moderated by dyad member's relative zBMI. Members of 145 same-gender best friendship dyads (56% female; Mage = 12.79; SDage = 0.61) reported on their intake of food obtained from home and from outside the home at the beginning and the end of the school year through food frequency questionnaires. Longitudinal Actor-Partner Interdependence Models results showed no indication of selection or socialization, and very limited evidence for the moderation of socialization processes by relative zBMI. These findings indicate that focusing on adolescent reciprocated best friends in dietary interventions may not be valuable.

Self-reported dietary changes among Los Angeles County adults during the COVID-19 pandemic.

Poor diets are historically the leading cause of morbidity and mortality in the United States (U.S.), causing over 44,000 deaths each month. Dietary patterns have likely changed during the COVID-19 pandemic due to major shifts and crises in social, economic, and food systems. This study examines self-reported dietary changes in Los Angeles (L.A.) County during COVID-19, and identifies factors associated with making healthy and unhealthy changes. Data are from the Understanding Coronavirus in America Study, an internet panel of adults representative of L.A. County households (N = 1080). Multinomial logistic regression was used to test if self-reported change in diet healthiness assessed in July 2020 was associated with socio-ecological factors known to be associated with diet, assessed between April-July 2020. More than half of L.A. County residents reported making changes to their diet: 28.3% reported eating healthier food since the beginning of the pandemic, while 24.8% reported eating less healthy food. Individuals who were significantly more likely to report healthy changes were Non-Hispanic Black or Hispanic/Latino (vs. Non-Hispanic White), had received unemployment insurance, or had larger social networks. Individuals who were significantly more likely to report unhealthy changes were younger, of mixed race, had children in their household, had transportation barriers, or had obesity. Individuals who were significantly more likely to report both healthy and unhealthy changes were Asian, had experienced food insecurity, or had challenges getting food due to store closures. The pandemic may be exacerbating diet-related disease risk in some groups, such as communities of color, and among individuals with obesity and those facing transportation barriers.

Social network interventions for health behaviours and outcomes: A systematic review and meta-analysis.

BACKGROUND: There has been a growing interest in understanding the effects of social networks on health-related behaviour, with a particular backdrop being the emerging prominence of complexity or systems science in public health. Social network interventions specifically use or alter the characteristics of social networks to generate, accelerate, or maintain health behaviours. We conducted a systematic review and meta-analysis to investigate health behaviour outcomes of social network interventions. METHODS AND FINDINGS: We searched eight databases and two trial registries from 1990 to May 28, 2019, for English-language reports of randomised controlled trials (RCTs) and before-and-after studies investigating social network interventions for health behaviours and outcomes. Trials that did not specifically use social networks or that did not include a comparator group were excluded. We screened studies and extracted data from published reports independently. The primary outcome of health behaviours or outcomes at ≤6 months was assessed by random-effects meta-analysis. Secondary outcomes included those measures at >6-12 months and >12 months. This study is registered with the International Prospective Register of Systematic Reviews, PROSPERO: CRD42015023541. We identified 26,503 reports; after exclusion, 37 studies, conducted between 1996 and 2018 from 11 countries, were eligible for analysis, with a total of 53,891 participants (mean age 32.4 years [SD 12.7]; 45.5% females). A range of study designs were included: 27 used RCT/cluster RCT designs, and 10 used other study designs. Eligible studies addressed a variety of health outcomes, in particular sexual health and substance use. Social network interventions showed a significant intervention effect compared with comparator groups for sexual health outcomes. The pooled odds ratio (OR) was 1.46 (95% confidence interval [CI] 1.01-2.11; I2 = 76%) for sexual health outcomes at ≤6 months and OR 1.51 (95% CI 1.27-1.81; I2 = 40%) for sexual health outcomes at >6-12 months. Intervention effects for drug risk outcomes at each time point were not significant. There were also significant intervention effects for some other health outcomes including alcohol misuse, well-being, change in haemoglobin A1c (HbA1c), and smoking cessation. Because of clinical and measurement heterogeneity, it was not appropriate to pool data on these other behaviours in a meta-analysis. For sexual health outcomes, prespecified subgroup analyses were significant for intervention approach (p < 0.001), mean age of participants (p = 0.002), and intervention length (p = 0.05). Overall, 22 of the 37 studies demonstrated a high risk of bias, as measured by the Cochrane Risk of Bias tool. The main study limitations identified were the inclusion of studies of variable quality; difficulty in isolating the effects of specific social network intervention components on health outcomes, as interventions included other active components; and reliance on self-reported outcomes, which have inherent recall and desirability biases. CONCLUSIONS: Our findings suggest that social network interventions can be effective in the short term (<6 months) and longer term (>6 months) for sexual health outcomes. Intervention effects for drug risk outcomes at each time point were not significant. There were also significant intervention effects for some other health outcomes including alcohol misuse, well-being, change in HbA1c, and smoking cessation.

Personal Network Characteristics as Predictors of Change in Obesity Risk Behaviors in Early Adolescence.

The potential for peers to influence obesity risk behavior increases in adolescence, yet there are knowledge gaps of how behaviors are modified in response to peers over time. This study examined how personal friendship network characteristics were associated with obesity-related behaviors from late childhood to early adolescence. Two waves of friendship, physical activity, screen time, and dietary recall data were collected from 11- to 13-year-old students (99% retention) in Australia (n = 308) over a five- to eight-month period. Regression models identified friendship network characteristics that predicted later health behaviors which varied by gender and behavior type, such as the number of friends positively associated with physical activity intensity (males) and screen time (females). The need for considering context to influence behavior change is discussed.

Analytic Strategies for Longitudinal Networks with Missing Data.

Missing data are often problematic when analyzing complete longitudinal social network data. We review approaches for accommodating missing data when analyzing longitudinal network data with stochastic actor-based models. One common practice is to restrict analyses to participants observed at most or all time points, to achieve model convergence. We propose and evaluate an alternative, more inclusive approach to sub-setting and analyzing longitudinal network data, using data from a school friendship network observed at four waves (N =694). Compared to standard practices, our approach retained more information from partially observed participants, generated a more representative analytic sample, and led to less biased model estimates for this case study. The implications and potential applications for longitudinal network analysis are discussed.

Protocol for a randomized controlled trial testing the impact of feedback on familial risk of chronic diseases on family-level intentions to participate in preventive lifestyle behaviors.

BACKGROUND: Common disease risk clusters in families due to shared genetics, exposure to environmental risk factors, and because many health behaviours are established and maintained in family environments. This randomised controlled trial will test whether the provision of a family health history (FHH) risk assessment tool increases intentions and engagement in health behaviors. Message distribution and collective behavior change within family networks will be mapped using social network analysis. The relative intervention impact will be compared between families from different ethnic backgrounds. METHODS: One hundred and fifty mothers (50 Anglo-Australian, 50 Italian-Australian, 50 Vietnamese-Australian) will be recruited, with four or more other family members across three generations, including a child (aged 10-18 years). Each family is randomly assigned to intervention or control. At baseline and 6-month follow-up, all participants complete surveys to assess dietary and physical activity intentions and behaviors, attitudes towards food, and perceived disease risk. Intervention families receive a visual pedigree detailing their FHH of diabetes, heart disease, breast and bowel cancer, a health education workbook to ascertain members' disease risk (i.e. average or above average risk), and screening and primary prevention recommendations. After completion of follow-up assessments, controls will receive their pedigree and workbook. The primary hypothesis is that attitudes and lifestyle behaviors will improve more within families exposed to FHH feedback, although the extent of this improvement may vary between families from different ethnic backgrounds. Additionally, the extent of improvement in the treatment group will be moderated by the level of family disease risk, with above-average risk leading to greater improvement. A secondary aim will explore different family members' roles in message distribution and collective responses to risk using social network approaches and to compare network functioning between families with different ethnic backgrounds. DISCUSSION: Results will guide future health promotion programs aimed at improving lifestyle factors. This research will assess whether FHH can motivate families to adopt family-level strategies to support health promoting behaviors. Secondary analyses aim to identify change agents within the family who are particularly effective in shifting normative behaviors. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12613001033730 . Retrospectively registered: 17 September, 2013.

The Power of Place: Social Network Characteristics, Perceived Neighborhood Features, and Psychological Distress Among African Americans in the Historic Hill District in Pittsburgh, Pennsylvania.

African American neighborhoods have been historically targeted for urban renewal projects, which impact social composition and resident's health. The Hill District in Pittsburgh, PA is such a neighborhood. This research sought to investigate the extent to which social networks and perceived neighborhood social cohesion and safety were associated with psychological distress among residents in an African American neighborhood undergoing urban renewal, before the implementation of major neighborhood changes. Findings revealed a modest, significant inverse association between social network size and psychological distress (ß = -0.006, p < .01), even after controlling for age, employment, education, and income. Perceived neighborhood safety predicted decreased psychological distress (ß = -1.438, p < .01), but not social cohesion, which is consistent with past research. Findings suggest that social networks protect against psychological distress, but neighborhood perceptions are also paramount.

Befriending Risky Peers: Factors Driving Adolescents' Selection of Friends with Similar Marijuana Use.

Adolescents often befriend peers who are similar to themselves on a range of demographic, behavioral, and social characteristics, including substance use. Similarities in lifetime history of marijuana use have even been found to predict adolescent friendships, and we examine whether this finding is explained by youth's selection of friends who are similar on a range of more proximate, observable characteristics that are risk factors for marijuana use. Using two waves of individual and social network data from two high schools that participated in Add Health (N = 1,612; 52.7% male), we apply longitudinal models for social networks to test whether or not several observable risky attributes (psychological, behavioral, and social) predict adolescent friendship choices, and if these preferences explain friend's similarities on lifetime marijuana use. Findings show that similarities on several risk factors predict friendship choices, however controlling for this, the preference to befriend peers with a similar history of marijuana use largely persists. The results highlight the range of social selection processes that lead to similarities in marijuana use among friends and larger peer groups, and that also give rise to friendship groups whose members share similar risk factors for substance use. Friends with high "collective risk" are likely to be important targets for preventing the onset and social diffusion of substance use in adolescents.

Predictors of parent-child relationships that support physical activity in Mexican-American families.

Family-based physical activity (PA) interventions would benefit from research that identifies how to build support for PA among family members. This study examined the extent to which relationships of encouragement to do PA, and co-engagement in PA, exist among Mexican-American parents and children, and sought to identify individual, relational, and household factors associated with these dimensions of support. Participants were 224 Mexican-origin adults, with at least one child aged 5-20 years, participating in a larger study conducted between 2008 and 2010. In baseline surveys, adult participants enumerated the names and attributes of their family and kin; this study focuses on 455 parent-child dyads, nested in 118 households. Parental encouragement of PA in their children was found in about half of dyads, and in 20 % of dyads children encouraged parents. Encouragement relationships were highly reciprocal. Reciprocal parent-child encouragement was also positively associated with co-participation in PA; the latter found in just 17 % of dyads. Results indicated that relational, individual, and socio-cultural attributes were associated with PA support among parents and children, and provide insights into how these relationships might be fostered within Mexican-American families.

Effect of mobile food environments on fast food visits.

Poor diets are a leading cause of morbidity and mortality. Exposure to low-quality food environments saturated with fast food outlets is hypothesized to negatively impact diet. However, food environment research has predominantly focused on static food environments around home neighborhoods and generated mixed findings. In this work, we leverage population-scale mobility data in the U.S. to examine 62M people's visits to food outlets and evaluate how food choice is influenced by the food environments people are exposed to as they move through their daily routines. We find that a 10% increase in exposure to fast food outlets in mobile environments increases individuals' odds of visitation by 20%. Using our results, we simulate multiple policy strategies for intervening on food environments to reduce fast-food outlet visits. This analysis suggests that optimal interventions are informed by spatial, temporal, and behavioral features and could have 2x to 4x larger effect than traditional interventions focused on home food environments.

New insights into grocery store visits among east Los Angeles residents using mobility data.

In this study, we employed spatially aggregated population mobility data, generated from mobile phone locations in 2021, to investigate patterns of grocery store visits among residents east and northeast of Downtown Los Angeles, in which 60% of the census tracts had previously been designated as "food deserts". Further, we examined whether the store visits varied with neighborhood sociodemographics and grocery store accessibility. We found that residents averaged 0.4 trips to grocery stores per week, with only 13% of these visits within home census tracts, and 40% within home and neighboring census tracts. The mean distance from home to grocery stores was 2.2 miles. We found that people visited grocery stores more frequently when they lived in neighborhoods with higher percentages of Hispanics/Latinos, renters and foreign-born residents, and a greater number of grocery stores. This research highlights the utility of mobility data in elucidating grocery store use, and factors that may facilitate or be a barrier to store access. The results point to limitations of using geographically constrained metrics of food access like food deserts.

Peer influence and selection processes in adolescent smoking behavior: a comparative study.

INTRODUCTION: Adolescent smoking studies find evidence of active peer influence and selection processes. However, studies have shown that these processes operate differently depending on context. This study uses SIENA to model coevolutionary processes between smoking and changes in friendship ties, comparing two high schools in which data were collected in identical fashion to explore influence and selection mechanisms with respect to current smoking, and smoking levels. METHODS: This is a longitudinal survey with 2 waves of data. In-home surveys were conducted with students from 2 large high schools in the United States: a West Coast school, and a Midwestern school. Participants were consented students in 10th and 11th grades at the first wave of data collection. The primary measures were self-reported smoking behavior and friendship nominations. RESULTS: There is evidence of influence and selection in both schools for adolescents' smoking status (1 = any smoking) and for level of smoking. CONCLUSIONS: These models reflect great similarities in influence and selection processes across schools for different smoking behaviors. However, smoking prevalence may impact the exact mechanisms by which influence and selection operate. Researchers should consider smoking interventions with independent modules addressing different selection and influence processes, implemented based on contextual factors such as the prevalence of smoking.

Perceptions of social circle vaccine acceptance and COVID-19 vaccine initiation among postpriority vaccine eligible adults.

OBJECTIVES: COVID-19 vaccines in the United States were made available to the general public aged 16 years and older in April 2021, but uptake in the months following was variable. We aimed to investigate this variability as a function of interpersonal factors, namely perceived social circle vaccine acceptance and proximity to illness, controlling for intrapersonal factors more often associated with vaccine behavior. METHOD: Data come from the Understanding Coronavirus in America tracking survey (February 2021-July 2021). We estimated the probability of vaccination among those who were unvaccinated as of April 14, 2021 (N = 2,199), the day before the announcement of general public eligibility. Stratified modeling by race accounted for subgroup differences. RESULTS: People who perceived social circle vaccine acceptance (Hazard Ratio [HR] = 1.37, p < .001), higher risk of infection (HR = 1.20, p < .001), greater trust in the vaccine (HR = 1.42, p < .001), and lower risk of vaccine side effects (HR = 0.77, p < .001) were more likely to get vaccinated. Perceptions of social circle vaccine acceptance were associated with vaccine initiation for all racial subgroups except Black respondents, for whom concerns about vaccine side effects were central. CONCLUSIONS: Perceived social circle vaccine acceptance was associated with time to the first dose of the COVID-19 vaccine. With public uncertainty about this new vaccine, people may have relied on perceptions of peers' vaccination intentions when deciding on their own vaccination. We discuss strategies for promoting vaccine uptake by intervening on perceptions of social norms. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Population mobility data provides meaningful indicators of fast food intake and diet-related diseases in diverse populations.

The characteristics of food environments people are exposed to, such as the density of fast food (FF) outlets, can impact their diet and risk for diet-related chronic disease. Previous studies examining the relationship between food environments and nutritional health have produced mixed findings, potentially due to the predominant focus on static food environments around people's homes. As smartphone ownership increases, large-scale data on human mobility (i.e., smartphone geolocations) represents a promising resource for studying dynamic food environments that people have access to and visit as they move throughout their day. This study investigates whether mobility data provides meaningful indicators of diet, measured as FF intake, and diet-related disease, evaluating its usefulness for food environment research. Using a mobility dataset consisting of 14.5 million visits to geolocated food outlets in Los Angeles County (LAC) across a representative sample of 243,644 anonymous and opted-in adult smartphone users in LAC, we construct measures of visits to FF outlets aggregated over users living in neighborhood. We find that the aggregated measures strongly and significantly correspond to self-reported FF intake, obesity, and diabetes in a diverse, representative sample of 8,036 LAC adults included in a population health survey carried out by the LAC Department of Public Health. Visits to FF outlets were a better predictor of individuals' obesity and diabetes than their self-reported FF intake, controlling for other known risks. These findings suggest mobility data represents a valid tool to study people's use of dynamic food environments and links to diet and health.