The endocrine stress response helps to maintain homeostasis in times of increased demand and supports survival through energy mobilization. Paradoxically, low blood glucose levels impede the endocrine stress response. Increasing blood glucose levels through sugar consumption prior to stress restores the endocrine response, suggesting that glucose availability may play a causal role in the endocrine stress response. However, sugar has distinct properties beyond the raise of blood glucose concentration. Further, potential psychological effects of expected calorie consumption have not been examined. We investigated the potential role of sweetness, energy load and energy prime in restoring the cortisol stress reactivity after fasting. N=152 women (meanage=21.53, sdage=2.61) participated in a psychosocial stress test for groups in the morning after an overnight fast. Prior to stress induction, participants were informed whether or not they consumed a caloric drink (energy prime) and consumed a sweet drink that contained calories (sugar, n=51), or not (sweetener, n=46). A control group consumed water (n=56). Salivary cortisol and blood glucose levels were assessed repeatedly. The effects on cortisol trajectories were tested using multilevel mixed models. While energy prime did not influence cortisol trajectories, sugar and sweetener each significantly increased the cortisol stress reactivity compared to water. Thereby, sweetener led to cortisol increases comparable to sugar. Changes in blood glucose levels after drink consumption were not significantly associated with stress-induced increases in cortisol. This suggests that hedonic properties of non-caloric and caloric sweetener consumption prior to stress are critical to restore the endocrine stress response after fasting.