Here’s a brilliant use of peanut butter…. to diagnose early stage Alzheimer’s disease. According to University of Florida Health researchers, all you need is a tablespoon of peanut butter and a ruler.
Why Test Your Nose for Alzheimer’s?
The ability to smell is associated with your first cranial nerve (the olfactory nerve) which is one of the first parts of your brain to deteriorate in Alzheimer’s disease. This nerve is located in your temporal lobe and that’s also where new memories are formed. Being unable to capture new information and remember it later is characteristic of Alzheimer’s disease.
Why Peanut Butter?
Peanut butter is used because it’s easy to access and exclusively detected by your olfactory nerve. In contrast, many smells are picked up by both your olfactory nerve and trigeminal nerve (the fifth cranial nerve).
The trigeminal nerve can cause physiological responses though, such as increased salivation, tearing, and nasal secretions (such as from an onion) which could affect detection results. Since peanut butter does not activate the trigeminal nerve, it’s an ideal test agent to isolate your olfactory nerve function. Doing so can link a diminished sense of smell with a degradation in specific areas of your brain.
The Smell Test
Testing for Alzheimer’s disease or other dementias can be time-consuming, costly and invasive. In contrast, here’s how the peanut butter test was conducted:
- Patient: Closed his/her eyes and mouth.
- Patient: Blocked one nostril.
- Clinician: Opened the peanut butter container (one tablespoon).
- Clinician: Held the ruler next to the open nostril while the patient breathed normally.
- Clinician: Moved the peanut butter up the ruler one centimeter at a time during the patient’s exhale until the person could detect an odor.
- Clinician: Recorded the distance.
- After 90 seconds, the procedure was repeated on the other nostril.
The Left-Right Results
The study revealed dramatic differences between the left and right nostril in patients with early stage Alzheimer’s disease. When smelling the peanut butter, the left nostril in the Alzheimer’s patients could not detect the smell of the peanut butter until it was an average of 10 centimeters closer to the nose than the right nostril had detected the smell.
In patients with other kinds of dementia, there were either no differences in odor detection between nostrils or the right nostril was worse at detecting odor than the left one.
Karen’s Fit Tip: Ask a friend or family member to test your sense of smell with other items, such as coffee, clove, pineapple, rose, lemon, peppermint, strawberry, and smoke. If you can’t identify any of them, you should talk to your physician.
A brief olfactory test for Alzheimer’s disease. Journal of the Neurological Sciences. Aug 2013.