Food anticipation and subsequent food withdrawal increase serum cortisol in healthy men

The anticipation of food intake comprises endocrine changes that according to animal experiments include a rise in HPA axis activity. In humans, HPA axis responses to food anticipation and withdrawal, although of clinical relevance, have not been thoroughly examined. We assessed neuroendocrine and psychological effects of food anticipation and of withholding anticipated food in healthy human subjects. Food anticipation was induced in 14 men at 0800 h by the announcement and subsequent presentation of a breakfast buffet. The expected meal was surprisingly withheld at 1000 h under the pretense of an organizational problem. Fifteen fasted controls were informed at 0800 h that they would remain fasted throughout the experiments. In both groups, hunger, mood and circulating concentrations of glucose, insulin, cortisol, ACTH, leptin and ghrelin were assessed. At 1200 h, all subjects were allowed to eat from a plate of cookies. Compared to non-anticipation, food anticipation was associated with a relative increase in serum cortisol levels, an acute drop in plasma glucose and increased self-rated hunger. When anticipated food was withheld, self-rated mood deteriorated and cortisol levels remained elevated, while plasma glucose levels decreased with a delay of 50 min. Other endocrine parameters and cookie intake were comparable between groups. Our results indicate that food anticipation without subsequent food reward increases cortisol levels and reduces blood glucose availability. They support the assumption that dietary restraint, being associated with habitually extended periods of anticipating food that is temporarily withheld, may contribute to the development of overweight by detrimental effects on HPA-axis activity.