Examination of the Biobehavioral Effects of Food Insecurity by Investigating Its Relationship to Changes in the Household Food Supply and Food Reward Sensitivity.

다국어 초록 (Multilingual Abstract)

Research has found a paradoxical relationship between food insecurity and increased obesity, which disproportionately affects low-income women. The relationship between food insecurity and obesity is mediated by diet quality where food insecurity has a negative effect on overall diet quality, promoting excess energy intake and subsequent weight gain. Some research indicates that there may also be intra-monthly changes in diet quality and food availability among women in food insecurity.Thus, the goal of this research was to understand the extent by which the availability of a variety of foods, a critical component of food insecurity, occurs at the household level and how it affects dietary intake patterns and liking for palatable foods. The objectives were to: 1) examine associations between food insecurity and monthly changes in variety of food available at the household level, 2) examine associations between food insecurity and changes in diet quality at a monthly level, 3) determine associations between food insecurity and food reward sensitivity using self-reported and brain fMRI scan assessments.A cross-sectional exploratory research study of 13 low-income adult women was conducted to address these objectives. Participants completed two telephone interviews and two brain Magnetic Resonance Imaging (MRI) scans in the beginning and end of month periods based on their typical monthly income cycles.Food insecurity was prevalent among participants (69%). Participants reported a low variety of fresh fruits and vegetables at both interviews, and the variety of these declined from the beginning to the end of month period. Overall diet quality was poor among participants, with an average HEI-2015 score of 45.2 in the beginning of the month and 50.8 in the end of the month compared to the maximum possible score of 100. Analysis of functional MRI (fMRI) results demonstrated the feasibility of using functional neuroimaging techniques to evaluate individual differences in brain activation for palatable and healthy food images among participants.These findings suggest low-income women experience intra-monthly changes in variety of food available in the household and individual diet quality. And, investigations of intra-monthly changes in the home food environment, diet quality, and fMRI activation for visual food stimuli are important for understanding the relationship between food insecurity and obesity among low-income women. This work contributes to a greater understanding of the biobehavioral effects of food insecurity, which influence dietary intake and ultimately nutrition related health outcomes in those experiencing food insecurity.