Abstract
Chromogranin A (CgA) levels and the novel pupil stress value (which was obtained by measuring the reaction of the eye pupil towards a flash of light) were employed as sensitive and substantial indices of psychosomatic stress to determine stress reduction activity of various foods. CgA levels showed a significant difference (P < 0.05) for cheese, whey protein, and hard biscuit compared with that for control water. The pupil stress value showed a significant difference (P < 0.05) for soft candy, cacao extract, milk, raw royal jelly, chewing gum, and γ-amino butyric acid (GABA). We developed a soft candy supplemented with cacao extract and whey protein that had a significant difference (P < 0.01) in stress reduction activity compared with that of water.
