Many Americans eat unhealthy, high-calorie/fat/sugar foods when stressed, yet little is known about whether this unhealthy comfort eating actually comforts. Additionally, prior research has not tested whether healthy comfort eating of fruits and vegetables might also alleviate stress, or whether comfort eating before or after a stressful event is more beneficial for stress relief. Accordingly, Study 1 experimentally tested whether healthy and unhealthy comfort eating would reduce acute psychophysiological responses to a socially evaluative stressor. Following a 2 x 2 + 1 design, participants (N = 150 women) were randomized to consume one of their top-rated healthy or unhealthy foods either before or after the stressor, or consumed no food. Psychological, neuroendocrine, and autonomic stress responses were examined. Findings revealed that healthy and unhealthy comfort eating did not dampen reactivity or enhance recovery of psychophysiological stress compared to control, and no differences were found by comfort eating type or timing. In a sample of 100 men and women, Study 2 evaluated whether individuals can learn to experience healthy foods as comforting, with the aim of also promoting healthy food intake. Applying Pavlovian conditioning methodology, intervention participants repeatedly paired together a relaxation activity and fruit intake for 7 days, whereas control participants completed these activities separately. At post-intervention, results showed that fruit intake acutely improved mood—but not autonomic stress markers—to a greater extent among the intervention group than the control group. There were no group differences in post-intervention intake of healthy and unhealthy foods outside of the lab, or in pre- to post-intervention changes in psychological outcomes, perceptions of fruit pleasantness, or intentions to buy fruits in the future. In conclusion, unhealthy comfort eating does not appear to benefit human psychophysiological stress responses. Healthy foods may not initially reduce stress, but they may acutely repair negative mood with training. Overall, healthy comfort eating may avoid potential drawbacks of unhealthy comfort eating (e.g., links with obesity) while also improving nutrition. These findings leave the door open for larger-scale interventions to transform unhealthy comfort eating to healthy comfort eating, thereby reducing negative emotion, promoting fruit intake, and decreasing chronic disease risk.

People engage in multiple behaviors that affect their health. There is little research on how these behaviors intersect within a person’s life. In this dissertation, I hypothesized that behaviors that activate the neural reward system can “compete.” In Study 1, I experimentally tested if eating sweet high-fat foods acutely reduced alcohol cravings for heavy drinking adults. I found that eating sweet high-fat foods acutely reduced alcohol cravings no more than watching a neutral video. In Study 2, I observed multiple reward-related behaviors (e.g., self-affirmation, social interactions, exercise) and health-compromising behaviors (e.g., unhealthy eating, alcohol use) within the everyday lives of young adults via a 4-day ambulatory electronic diary. I found that when young adults engaged in multiple reward-related behaviors they were more likely to eat unhealthy foods in the next hour. However, when young adults engaged in reward-related behaviors that provided a sense of accomplishment they were less likely to drink alcohol in the next hour. These studies fill scientific gaps in understanding intersections between reward-related behaviors and provide insight for health behavior change. Namely, that “replacing” health-compromising behavior with other reward-related behaviors may not consistently work.