New research shows a tablespoon of peanut butter and a ruler might help diagnose early-stage Alzheimer's disease.
University of Florida researchers studied how long it took patients to detect the smell of peanut butter.
Patients closed their eyes and mouths and blocked one nostril in the test. Then a tablespoon of peanut butter on a ruler was moved closer to the person's nose until they could detect the smell.
Patients in early stages of Alzheimer's took longer to detect the odor from the left nostril versus the right one.