Social Isolation, Brain Food Cue Processing, Eating Behaviors, and Mental Health Symptoms.

Importance: Perceived social isolation is associated with negative health outcomes, including increased risk for altered eating behaviors, obesity, and psychological symptoms. However, the underlying neural mechanisms of these pathways are unknown. Objective: To investigate the association of perceived social isolation with brain reactivity to food cues, altered eating behaviors, obesity, and mental health symptoms. Design, Setting, and Participants: This cross-sectional, single-center study recruited healthy, premenopausal female participants from the Los Angeles, California, community from September 7, 2021, through February 27, 2023. Exposure: Participants underwent functional magnetic resonance imaging while performing a food cue viewing task. Main Outcomes and Measures: The main outcomes included brain reactivity to food cues, body composition, self-reported eating behaviors (food cravings, reward-based eating, food addiction, and maladaptive eating behaviors), and mental health symptoms (anxiety, depression, positive and negative affect, and psychological resilience). Results: The study included 93 participants (mean [SD] age, 25.38 [7.07] years). Participants with higher perceived social isolation reported higher fat mass percentage, lower diet quality, increased maladaptive eating behaviors (cravings, reward-based eating, uncontrolled eating, and food addiction), and poor mental health (anxiety, depression, and psychological resilience). In whole-brain comparisons, the higher social isolation group showed altered brain reactivity to food cues in regions of the default mode, executive control, and visual attention networks. Isolation-related neural changes in response to sweet foods correlated with various altered eating behaviors and psychological symptoms. These altered brain responses mediated the connection between social isolation and maladaptive eating behaviors (ß for indirect effect, 0.111; 95% CI, 0.013-0.210; P = .03), increased body fat composition (ß, -0.141; 95% CI, -0.260 to -0.021; P = .02), and diminished positive affect (ß, -0.089; 95% CI, -0.188 to 0.011; P = .09). Conclusions and Relevance: These findings suggest that social isolation is associated with altered neural reactivity to food cues within specific brain regions responsible for processing internal appetite-related states and compromised executive control and attentional bias and motivation toward external food cues. These neural responses toward specific foods were associated with an increased risk for higher body fat composition, worsened maladaptive eating behaviors, and compromised mental health. These findings underscore the need for holistic mind-body-directed interventions that may mitigate the adverse health consequences of social isolation.

The role of income and neighbourhood poverty in the association between the 2009 Special Supplemental Nutrition Program for Women, Infants and Children (WIC) food package change and child obesity among WIC-participating children in Los Angeles County, 2003-2016.

OBJECTIVE: To determine whether a previously reported association between the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) food package change and reduced child obesity risk among WIC-participating children in Los Angeles County holds across levels of family income and neighbourhood poverty. DESIGN: Analysis of prospectively collected WIC administrative data. The outcome was obesity at age 4 years (BMI-for-age ≥ 95th percentile). Poisson regression was applied to a matched sample (n 79 502) to determine if the association between the WIC food package change and child obesity was modified by family income (<50 % federal poverty level (FPL), 50-100 % FPL, >100 % but <185 % FPL) and neighbourhood poverty. SETTING: Los Angeles County, California. PARTICIPANTS: Children who participated in WIC in Los Angeles County between 2003 and 2016; children were grouped as receiving the old WIC food package (2003-2009) or the new WIC food package (2010-2016). RESULTS: Receiving the new WIC food package (i.e., post-2009) was associated with 7-18 % lower obesity risk across all family income categories. Neither family income nor neighbourhood poverty significantly modified the association between the WIC food package and child obesity. However, certain sub-groups seemed to benefit more from the food package change than others. In particular, boys from families with income above poverty but residing in the poorest neighbourhoods experienced the greatest reductions in obesity risk (relative risk = 0·77; 95 % CI 0·66, 0·88). CONCLUSIONS: The WIC food package revisions were associated with reduced childhood obesity risk among all WIC-participating families in Los Angeles County, across levels of income eligibility and neighbourhood poverty.

Every month matters: longitudinal associations between exclusive breastfeeding duration, child growth and obesity among WIC-participating children.

BACKGROUND: Research has found breastfeeding to be protective of obesity; however, this link remains contentious. We examined longitudinal associations between exclusive breastfeeding duration, growth trajectories and obesity at 4 years among children participating in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC), and whether these associations differed in the context of the 2009 WIC food package change, implemented to improve alignment with dietary guidelines and promote breastfeeding. METHODS: Longitudinal data from 260 935 WIC-participating children in Los Angeles County, California, 2003-2016, were used to assess the relationship between duration of receipt of the fully breastfeeding package (an exclusive breastfeeding proxy) with childhood growth and obesity using mixed effects and Poisson regression models. RESULTS: Children exclusively breastfed for longer duration had healthier growth trajectories and lower obesity risk at age 4. Compared with infants with no fully breastfeeding package receipt, any receipt (a breastfeeding initiation proxy) was associated with reduced obesity risk. Obesity risk was lowest for boys and girls exclusively breastfed for 7 (risk ratio (RR)=0.73, 95% CI=0.64 to 0.82) and 13 months (RR=0.63, 95% CI=0.58 to 0.69), respectively. Exclusive breastfeeding duration increased, but associations between exclusive breastfeeding duration and growth and obesity were not modified, following the 2009 WIC food package change. CONCLUSION: Increased duration of exclusive breastfeeding was associated with reduced obesity risk. The greatest incremental benefit was observed going from none to any exclusive breastfeeding, and the maximum cumulative benefit was among children receiving the fully breastfeeding package for more than 6 months. Breastfeeding promotion in WIC remains important for obesity prevention.

Economic evaluation of California prenatal participation in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) to prevent preterm birth.

There is growing evidence that prenatal participation in the Special Supplemental Nutrition Program for Women, Infants and Children (WIC) reduces the risk of adverse birth outcomes. With recent changes in health care, rising health care costs, and increasing rates of prematurity in the U.S., there is urgency to estimate the potential cost savings associated with prenatal WIC participation. A cost-benefit analysis from a societal perspective with a time horizon over the newborn's life course for a hypothetical cohort of 500,000 Californian pregnant women was conducted in 2017. A universal coverage, a status quo ('business as usual') and a reference scenario (absence of WIC) were compared. Total societal costs, incremental cost savings, return on investment, number of preterm births prevented, and incremental net monetary benefits were reported. WIC resulted in cost-savings of about $349 million and the prevention of 7575 preterm births and would save more if it were universal. Spending $1 on prenatal WIC resulted in mean savings of $2.48 (range: $1.24 to $6.83). Decreasing prenatal WIC enrollment by 10% would incur additional costs (i.e. loss) of about $45.3 million to treat the resulting 981 preterm babies. In contrast, a 10% increase in prenatal WIC enrollment would prevent 141 preterm births and achieve additional cost-savings of $6.5 million. The findings confirm evaluations from the early 1990s that prenatal WIC participation is cost-saving and cost-effective. Further savings could be achieved if all eligible women were enrolled in WIC. Substantial preterm birth-related costs would result from reductions in WIC participation.

Validity of child anthropometric measurements in the Special Supplemental Nutrition Program for Women, Infants, and Children.

INTRODUCTION: The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) serves 50% of infants and 25% of preschool-aged children in the United States and collects height and weight measurements from eligible children every 6 mo, making WIC data a valuable resource for studying childhood growth and obesity. We assessed the accuracy of measurements collected by WIC staff by comparing them to "gold standard" measurements collected by trained research staff. RESULTS: Intraclass correlation coefficients (ICCs) measuring agreement between WIC and research protocol measurements for height, weight, and BMI were 0.96, 0.99, and 0.93, respectively. Although WIC measurements overestimated height by 0.6 cm and weight by 0.05 kg on average, BMI was underestimated by only 0.15 kg/m(2) on average. WIC BMI percentiles classified children as overweight/obese vs. underweight/normal with 86% sensitivity and 92% specificity. DISCUSSION: We conclude that height, weight, and BMI measurements of children aged 2-5 y collected by trained WIC staff are sufficiently accurate for monitoring and research purposes. METHODS: At seven WIC clinics in southern California, 287 children aged 2-5 y measured for height and weight by WIC staff using WIC standard protocol were remeasured by research staff using a research protocol (duplicate measurements with shoes and outerwear removed were taken by trained personnel).