Silvia Maier, in a study published in Neuron, showed that stress may negatively impact decision making and self-control. This study by a Swiss graduate student, revealed that when stressed people indicated preferences for tasty food over healthy food.
Stress, in this study was manipulated by subjects having their hands plunged into cold water for several minutes. This way of inducing stress has often been used in hard science research. Cortisol was a mediating factor noted in the study conducted in Zurich Switzerland. The study was small and involved 29 persons, and did not measure anxiety levels but instead just focused on normal stress pathways.