Many people associate the earliest signs of Alzheimer’s disease with memory loss, such as forgetting names or misplacing everyday items. While memory changes are common, researchers have found that some early changes may involve an entirely different sense: smell.
One surprisingly subtle clue may be difficulty recognizing familiar scents, such as the smell of your regular soap while taking a shower. Although this symptom alone is not enough to diagnose Alzheimer’s disease, it may provide useful information when considered alongside other cognitive changes.
Why the Sense of Smell Matters
The ability to recognize odors is closely connected to areas of the brain involved in memory and learning.
Researchers have found that these regions may be affected early in Alzheimer’s disease, which can make it harder for some individuals to correctly identify familiar smells before more noticeable memory problems develop.
For this reason, changes in the sense of smell have become an area of growing interest in Alzheimer’s research.
Researchers have also investigated whether a simple smell-identification test could help identify people who may be at greater risk of future cognitive decline. Some findings have been encouraging.
A Simple Smell-Identification Test
In a long-term study involving more than 1,000 participants, researchers asked volunteers to identify a variety of common everyday scents.
Examples included:
- Soap
- Smoke
- Rose
- Leather
The researchers found that participants who had greater difficulty identifying familiar odors were more likely to develop cognitive impairment during follow-up.
When combined with brief memory assessments, smell testing provided additional useful information and, in some situations, showed results comparable to more advanced screening approaches.
Why Early Detection Matters
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