The Smell of Peanut Butter Could Diagnose Alzheimer's

We may earn a commission from links on this page.

On the heels of the recent discovery that accelerometers could be used as indicators for Alzheimer's disease comes yet another potential diagnostic tool, one that most of us already have in our pantries: peanut butter.

Alzheimer's often impacts the olfactory cortex first and, as such, compromises our sense of smell, specifically in the brain's left hemisphere. Now, most odors actually trigger both our olfactory and trigeminal systems, the latter of which explains why we cry while cutting onions. But researchers at the University of Florida have found a loophole by harnessing the power of peanut butter, a "pure odorant" that only involves the olfactory pathway.


In their pilot study, patients were presented with a tablespoon of peanut butter and then asked to close their eyes and mouth while blocking one nostril. The physician then held a ruler to their open nostril and slowly moved the peanut butter closer in 1 centimeter increments, until the patient could smell it. The findings were consistent with the pattern of Alzheimer's degradation: those with the disease couldn't detect the scent in their left nostril until the peanut butter was an average of 10 centimeters closer than on the right side. As it turns out, this result wasn't replicated in patients with other cognitive disorders.

This test could give us a simple, straightforward way to diagnose Alzheimer's, and it could be particularly useful in, say, rural clinics that might lack the equipment required to conduct more complex testing. That said, let's leave it to the professionals—this shouldn't give hypochondriacs carte blanche to start compulsively sniffing peanut butter. [University of Florida via PopSci]