Research links food insecurity in early life and pregnancy to higher rates of child obesity

19 Sep 2024 --- Food insecurity in the early lives of children or their pregnant mothers increases kids’ chance of developing obesity or severe obesity in childhood and adolescence by 50%, according to new research. Moreover, these children also had a higher Body Mass Index (BMI) at ages five and 15.

The associations became more robust as children aged and were most significant among kids who lived in low-income, low-food-access neighborhoods both during early childhood and their mother’s pregnancy. In these areas, a third or more residents live at least 0.5 miles (0.8 km) from a grocery store in urban areas or at least 10 miles (16 km) in rural areas. 

The study was funded by the National Institutes of Health program Environmental influences on Child Health Outcomes (ECHO). Researchers examined data from 28,359 children and their mothers from 55 ECHO Cohort research sites throughout the US. 

“Understanding how experiencing food insecurity during pregnancy and early childhood impacts subsequent child obesity is essential,” lead author Izzuddin Aris, Ph.D., assistant professor at the Harvard Pilgrim Health Care Institute, US, tells Nutrition Insight. 

“By unraveling the mechanisms and identifying risk factors linking neighborhood food access and obesity in children, we hope the findings of this study can inform targeted preventive strategies that may mitigate obesity-related chronic conditions in the future.”

He underscores that the study’s findings support a focus on investments or strategies to improve healthful food access in early life. 

“This includes incentivizing new supermarkets in existing low-income, low-food-access neighborhoods, providing healthy-choice pantries and improving access to healthier food choices in small retail corners and convenience stores. Such investments could play a crucial role in reducing food insecurity, preventing child obesity and promoting healthier communities.”

“Alarmingly high” food insecurity

The researchers note that US food insecurity among households with children under 18 remains “alarmingly high.” Recent data indicates that 17.9% of US households with children experienced food insecurity at some point in 2023. In around half of these households, both children and adults were food insecure. 

However, Aris details that the few longitudinal studies of food insecurity and child obesity overlook earlier life stages, such as pregnancy or early childhood, that “are more developmentally plastic and may be more sensitive in influencing long-term health outcomes.” Instead, earlier studies focused primarily on food insecurity in later childhood or adolescence. 

In low-food-access neighborhoods, a third of residents live at least 0.8 km (urban areas) or 16 km (rural areas) from a grocery store.“Also, they were conducted only within a single US city or state, which reduces generalizability to the US population.”

“Our study directly addressed these key research gaps by examining neighborhood food access during pregnancy and early childhood in several cohorts across the US, thus contributing novel evidence to the growing body of literature linking neighborhood food access in early life with subsequent child obesity.”

Low-food access neighborhoods

The study, published in JAMA Pediatrics, used participants’ residential addresses from either pregnancy (from 1994 to 2023) or early childhood (1999–2023). The researchers found that about 23% of included children had mothers who lived in an area with limited access to grocery stores during pregnancy, and 24% lived in these areas during early childhood. 

The team gathered data on children’s weight and height from birth to adolescence through in-person visits, medical records and parent or caregiver reports. 

After adjusting for individual socio-demographic conditions, they found that residence in low-income, low-food-access neighborhoods compared to living in non-low-income, low-food-access areas in pregnancy was associated with higher child BMI scores and higher obesity and severe obesity at ages 5, 10 and 15. 

Findings were similar for residents in low-income, low-food access areas during early childhood. 

In an earlier study of ECHO participants, researchers found that living in the lowest opportunity neighborhoods in early life was associated with an approximately 80% higher obesity risk at similar life stages. 

The researchers highlight that these findings suggest that “pregnancy and early childhood are both important windows of exposure concerning neighborhood food access and that residence in neighborhoods with better food access during these life stages might constitute an important resilience factor that may prevent development of child obesity.”

Aris suggests there may be more fast food consumption, increased stress levels and lower physical activity in these areas.Possible explanations

Aris notes that several potential mechanisms may underlie the identified observations. 

“Low-income, low-food-access neighborhoods might have a greater density of smaller convenience stores and fast food outlets, which implies a greater access to and increased consumption of highly processed and packaged foods containing obesogens often sold in these stores. Thus, greater access to these stores could impair the diet quality of pregnant individuals and children, which may subsequently affect child obesity,” he suggests. 

“Individuals residing in low-income, low-food access neighborhoods, including children, may also face higher levels of stress due to the financial and emotional pressures of food insecurity, poor housing, adverse childhood events or neighborhood crime, which may lead to weight gain through stress-induced metabolic changes.” 

Moreover, Aris suspects that low-income, low-food-access neighborhoods could also reflect disadvantaged neighborhood conditions with poorer built environment characteristics that discourage physical activity or higher exposure to other environmental stressors that can affect child health outcomes. 

“Hence, beyond affecting children’s diet quality, residence in low-income, low-food-access neighborhoods may negatively affect child obesity through reduced physical activity or increased exposure to obesogenic stressors including environmental pollutants.”

The researchers highlight that follow-up research should examine the effectiveness of investments in neighborhood resources to improve food access and prevent child obesity. 

In addition, Aris says that future ECHO studies will “explore potential mechanisms linking residence in low-income, low-food access neighborhoods and subsequent child obesity.”

By Jolanda van Hal