Examining the effect of hunger on responses to pathogen cues and novel foods

Although multiple leading papers in the behavioral immune system literature have proposed that food deprivation affects responses to pathogen cues, evidence supporting this proposition is scarce. Here, we report results from what we believe to be the most comprehensive test of the effects of hunger on responses to pathogen cues to date. Participants (N = 40) recruited from a Dutch university attended two experimental sessions, each following a 15-hour fast. One of the two sessions was conducted immediately after eating a standardized meal, and the other was conducted before eating that same standardized meal. In each session, participants rated 40 different images (i.e., images depicting food-related pathogen cues, food-unrelated pathogen cues, violence, positive stimuli, and neutral stimuli) on valence and arousal while their heart rate and skin conductance responses were recorded. They also indicated their willingness to eat 16 novel foods. Results did not reveal an effect of nutritional state on explicit ratings of and physiological reactions to food-related or food-unrelated pathogen cues. However, participants reported a greater willingness to eat novel foods when hungry than when sated. These results raise doubt regarding proposals that short-term changes in nutritional state influence responses to pathogen cues, but they suggest that these same changes increase willingness to eat novel foods.