How Well We Smell Predicts How Long We'll Live

Olfaction is an important sensory system in mammals, and olfactory dysfunction can be an early manifestation of neurodegenerative disease in humans. To determine whether olfactory dysfunction is associated with mortality, researchers prospectively studied a nationally representative sample of 3005 older U.S. adults (age range, 57–85) for 5 years. In addition to collecting detailed clinical and demographic information, the researchers tested olfactory function using a validated identification test for odors (rose, leather, orange, fish, and peppermint).

After controlling for numerous potentially confounding variables, anosmic and hyposmic people were approximately 3.4 times and 1.5 times, respectively, more likely to die during the study than…