Recalled and momentary virtual portions created of snacks predict actual intake under laboratory stress condition

The Universal Eating Monitor (UEM): objective assessment of food intake behavior in the laboratory setting

The Universal Eating Monitor was a term used to describe a device used in a laboratory setting that enabled investigators to measure, with the same instrument, the rate of eating either solids or liquids, hence the term “universal”. It consisted of an electronic balance placed in a false panel under a table cloth on which could be placed a food reservoir that contained either solid or liquefied food. The device was created in order to determine whether rates of eating differed in pattern between solid and liquid foods. An acceptable mixture of foods of identical composition that could be served as either solid or blended as a liquid was used to test the hypothesis that eating rate and intake were affected by physical composition. A best-fitting mathematical function (intake was quadratic function of time, with coefficients varying among foods used and experimental conditions), quantified intake rates. The device was used to test a variety of mechanisms underlying food intake control. Eating rates were linear when solid foods were used, but negatively accelerated with liquids. Overall, intake did not differ between solid and liquefied food of identical composition. Satiation on a calorie for calorie basis was different among foods, but physical composition interacted with energy density. Hormones and gastric distension were strong influences on food intake and rate of eating. Individuals with bulimia nervosa and binge eating disorder ate more than individuals without these disturbances. Intake in social and individual contexts was identical, but the rate of eating was slower when two individuals dined together. The eating monitor has been a useful instrument for elucidating controls of food intake and describing eating pathology.

Self-reported emotional eaters consume more food under stress if they experience heightened stress reactivity and emotional relief from stress upon eating

Group data means from individuals who self-assess as emotional eaters do not reliably show increased food intake in response to stress or negative emotions. This inconsistency in predictive validity of self-reported emotional eating (EE) could be attributable to unconsidered moderation of the relationship between self-reported EE and behavioral measures of EE. Greater emotional relief from stress by eating may provide enhanced negative reinforcement and promote future EE in response to stress as a form of self-medication. Thus, we predicted that greater emotional relief from stress by eating (decrease in negative affect from stress to post-eating) would moderate the extent to which heightened stress reactivity (measured by systolic blood pressure, SBP) moderates the relationship between self-reported EE and food intake post-stress. We also hypothesized that self-reported EE would not predict greater food consumption on the rest day. 43 undergraduate women completed online assessments of eating behaviors. Participants were given snacks to eat after a mental stress task (TSST) or rest period on separate days in counterbalanced order. Our prediction was supported, as the moderated moderation model (PROCESS model 3) was highly significant on the stress day. Self-reported EE predicted increased food intake post-stress only under conditions of high stress reactivity and high emotional relief. On the rest day, self-reported EE predicted greater snack food intake only when SBP was high. This conditional increased intake substantiates stress as a promoter of snack food consumption for women with greater EE. Overall, our findings identified factors that may distinguish the subset of self-reported emotional eaters who are more likely to display EE behaviors in a laboratory setting, yet further studies are needed to directly test whether negative reinforcement via emotional relief from stress by eating drives enhanced EE following stress.