The hormone cortisol rises and falls naturally throughout the day and can spike in response to stress. Current methods for measuring cortisol levels require waiting several days for results from a laboratory. By the time a person learns the results of a cortisol test (which may inform treatment for certain medical conditions) it is likely to be different from when the test was taken. Now, a group of scientists in the U.S. and France have created a stretchy patch that wicks up sweat and assesses how much cortisol a person is producing. The patch is applied directly to the skin. Clinical tests that measure cortisol provide an objective gauge of emotional or physical stress in research subjects and can help doctors tell if a patient’s adrenal or pituitary gland is working properly. If the prototype version of the wearable device becomes a reality, it could allow people to monitor their own levels at home. A paper about the wearable sensor has been published in Science Advances .
