Researchers at the University of Florida have discovered that peanut butter may help diagnose Alzheimer's disease early on, using a simple and inexpensive olfactory test.
For a small pilot study lead by graduate student Jennifer Stamps and her colleagues, participants with Alzheimer's disease, mild cognitive impairment and other forms of dementia were asked to close their eyes and one nostril at a time and try and detect the odor of peanut butter at different lengths from their noses.
Previous research has linked degeneration in the temporal lobe, the part of the brain that controls senses and forming new memories, to Alzheimer's and dementia. While working in Dr. Kenneth Heilman's neurology and health psychology clinic, Stamps noted that patients were not tested for their sense of smell, one of the first things affected by cognitive decline.
She was told by Dr. Heilman, "If you can come up with something quick and inexpensive, we can do it."
So Stamps opted for peanut butter, a "pure ordorant" that is only detected by the olfactory nerve and easy to come by. In her subsequent study, Stamps had participants sit down with a clinician in front of 14 grams of peanut butter and had them close the right and then the left nostril and see from how far away they could smell it as the clinician moved the teaspoon up and down on a ruler.
As it turns out, of the 24 participants in the new study, those who were in the early stages of Alzheimer's disease (around 10) had a more difficult time smelling the peanut butter from their left nostril when compared to their left nostril, a phenomenon which did not occur in patients with other cognitive disorders. Their left nostril was impaired by about a 10 centimeter distance as compared to their right.
For patients with other forms of dementia or cognitive impairment, they had no difference in odor detection between nostrils.
"All of the Alzheimer's patients had a left nostril impairment and the right nostril was normal," Stamps said in a press release. "At the moment, we can use this test to confirm diagnosis. But we plan to study patients with mild cognitive impairment to see if this test might be used to predict which patients are going to get Alzheimer's disease."
Stamps and Heilman think that this inexpensive and simple test can be used in clinics that do not have access to more elaborate testing methods or personnel that could be costly, invasive and time-consuming.
