Summary: Living in disadvantaged neighborhoods not only shapes food choices and increases risk of weight gain but can also alter the brain’s microstructure.
A UCLA study found that the limited food quality, higher calorie intake from unhealthy sources, and environments that discourage physical activity common in deprived areas are associated with changes in brain regions responsible for emotion, cognition, and reward processing. The researchers identified a direct relationship between alterations in the cortical microstructure and higher intake of trans‑fatty acids—nutrients often consumed in fried and fast foods prevalent in these communities.
These results underscore the urgency of improving dietary options in disadvantaged neighborhoods to protect brain health and cognitive function.
Key Facts:
- Neighborhood disadvantage is linked to changes in the brain’s cortex, particularly in areas involved in reward, emotion regulation, and higher cognition, likely driven by poor dietary habits and obesogenic environments.
- The study analyzed 92 adults using advanced MRI measures to examine cortical microstructure in relation to the Area Deprivation Index (ADI).
- Higher intake of trans‑fatty acids—common in fried and processed foods—was associated with specific cortical changes and helped explain part of the link between neighborhood disadvantage and brain microstructure.
Source: UCLA
“You are what you eat” may be truer for the brain than we realized. Researchers at the UCLA David Geffen School of Medicine show that living in a disadvantaged neighborhood can influence diet, body weight, and even the fine structure of the cerebral cortex.
Published in Communications Medicine, the study examined how features common to disadvantaged neighborhoods—poor access to healthy foods, increased calories from trans‑fatty acids, and limited opportunities for physical activity—are associated with alterations in cortical microstructure. These cortical changes may disrupt the brain’s flexibility in processing information related to reward, emotional regulation, and cognitive tasks.
While previous work connected neighborhood disadvantage to poorer brain outcomes in general, this study performed a more detailed cortical analysis to identify which cortical layers and regions are most affected.
“We found that neighborhood disadvantage was associated with differences in the fine structure of the cortex,” said Arpana Gupta, PhD, co‑director of the Goodman‑Luskin Center and director of the Neuroimaging Core. “Some of these differences were linked to higher body mass index and correlated with high intake of trans‑fatty acids commonly found in fried fast food.”
Gupta, the study’s senior author, added: “Regions of the brain involved in reward, emotion, and the acquisition of knowledge may be affected by neighborhood factors that contribute to obesity. Our findings highlight the importance of improving dietary quality in disadvantaged communities to protect brain health.”
Neighborhood disadvantage was measured using the Area Deprivation Index (ADI), a composite metric that includes factors such as lower median income, lower education levels, household crowding, and limited infrastructure.
The study included 92 participants (27 men and 65 women) from the greater Los Angeles area. Researchers collected demographic and body mass index (BMI) data and used the Neighborhood Atlas ADI to characterize residential disadvantage. Dietary information was gathered for most participants to assess intake of nutrients including trans‑fatty acids.
Participants underwent two complementary MRI protocols that, when analyzed together, provide detailed information about brain structure and tissue properties. The research focused on T1‑weighted/T2‑weighted (T1w/T2w) ratio measures across four cortical ribbon depths—deep, lower‑middle, upper‑middle, and superficial—to capture layer‑specific microstructural variations.
“Different cell populations occupy different cortical layers, each with distinct signaling mechanisms and roles in information processing,” said Lisa Kilpatrick, PhD, the study’s first author. “By examining microstructure across cortical depths, we gain a clearer picture of how neighborhood disadvantage might affect cellular populations and communication pathways in the brain.”
Study results showed that higher ADI scores were associated with increased BMI and greater perceived stress. Cortical microstructure alterations included decreased T1w/T2w ratios in middle and deeper cortical layers in regions such as the supramarginal gyrus, temporal areas, and primary motor cortex, and increased T1w/T2w ratios in superficial layers of medial prefrontal and cingulate regions. Higher BMI partially mediated the relationship between neighborhood disadvantage and some of the cortical changes, and trans‑fatty acid intake correlated with the observed increases in T1w/T2w ratio.
Taken together, these findings suggest that obesogenic characteristics of disadvantaged neighborhoods—especially poor dietary quality—may interfere with the brain’s information‑processing flexibility in networks that support reward, emotion regulation, and cognition.
Authors: Arpana Gupta and Lisa Kilpatrick (corresponding authors), with coauthors Keying Zhang, Tien Dong, Gilbert Gee, Hiram Beltran‑Sanchez, May Wang, Jennifer Labus, Bruce Naliboff, and Emeran Mayer, all affiliated with UCLA.
Funding: This work was supported by grants from the National Institutes of Health (including R01 MD015904, K23 DK106528, R03 DK121025, T32 DK07180, ULTR001881/DK041301, R01 DK048351, and P30 DK041301) and pilot funds for brain scanning from the Ahmanson‑Lovelace Brain Mapping Center. Funders did not influence study design, data collection, analysis, interpretation, or reporting.
About this neuroscience and psychology research news
Author: David Sampson
Source: UCLA
Contact: David Sampson – UCLA
Image: The image is credited to Neuroscience News
Original Research: Open access. “Mediation of the association between disadvantaged neighborhoods and cortical microstructure by body mass index” by Arpana Gupta et al., Communications Medicine.
Abstract
Mediation of the association between disadvantaged neighborhoods and cortical microstructure by body mass index
Background
Living in a disadvantaged neighborhood is linked to poorer health outcomes, including compromised brain health, yet the biological pathways remain unclear. This study assessed the relationship between neighborhood disadvantage and cortical microstructure—measured using the T1w/T2w ratio on MRI—and tested whether body mass index (BMI) and perceived stress mediate that relationship. The study also examined how intake of trans‑fatty acids relates to cortical microstructure.
Methods
Ninety‑two adults (27 men, 65 women) provided residential addresses and underwent neuroimaging. Neighborhood disadvantage was quantified using the 2020 California ADI. The T1w/T2w ratio was computed at four cortical depths (deep, lower‑middle, upper‑middle, superficial). Perceived stress and BMI were evaluated as potential mediators. Dietary intake was recorded for 81 participants.
Results
Worse ADI correlated with higher BMI (r = 0.27, p = 0.01) and greater perceived stress (r = 0.22, p = 0.04). ADI was associated with decreased T1w/T2w ratios in middle and deep cortex of supramarginal, temporal, and primary motor regions (p < 0.001), and increased T1w/T2w ratios in superficial cortex of medial prefrontal and cingulate regions (p < 0.001). Increased BMI partially mediated the association between higher ADI and certain T1w/T2w increases (p = 0.02). Trans‑fatty acid intake correlated with those T1w/T2w increases (p = 0.03).
Conclusions
Obesogenic aspects of neighborhood disadvantage, particularly poor dietary quality, may disrupt the flexibility of information processing in brain regions involved in reward, emotion regulation, and cognition. These results point to meaningful consequences of living in a disadvantaged neighborhood for brain health.