Abstract
Increased consumption of highly processed foods may result in lower diet quality, and low diet quality is associated with elevated risk of cardiovascular disease, type 2 diabetes, and cancer. One mechanism driving highly processed food intake is the expectation that eating these foods will improve emotional experiences, particularly in individuals with elevated "highly processed food addiction" symptoms. However, experimental findings about the emotional experiences following highly processed food intake are mixed. Furthermore, prior studies have generally failed to capture the potentially prolonged emotional effects of eating highly processed foods and not tested for individual differences. The present study was a preregistered archival data analysis of an ambulatory electronic diary study that captured real-life emotions following highly processed food intake. Multilevel modeling was used to predict the effects of highly processed food intake on subsequent positive and negative emotions immediately, 1 h, and 3 h after consumption. Intake of sweet high-fat foods, fast foods, and non-alcoholic sugary drinks was associated with greater positive emotions immediately after eating, and sweet high-fat food intake remained associated with greater positive emotions 1 h later. Sweet high-fat food and non-alcoholic sugary drink intake were associated with fewer negative emotions 1 h after consumption, and the negative association between non-alcoholic sugary drink intake and negative emotions was stronger for those with elevated highly processed food addiction symptoms. Overall, results suggest that highly processed food intake results in small alterations in positive and negative emotions immediately and up to 1 h after intake; however, these do not persist through 3 h after intake. The ability of highly processed foods to briefly alter emotions may be key to their reinforcing nature.