Alzheimer's & dementiaBrain & nervous system

7 surprising signs of dementia

Be on the lookout for these signs your brain health is at risk.


LearnBrain & nervous system7 surprising signs of dementia
You’re having dental problems
You start walking differently
You’ve been sleeping more (or less)
You can’t find the words
Your judgment and self-control change
You display inappropriate sexual behavior
Your sense of smell is off

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Memory impairment is probably the best-known symptom of dementia conditions including Alzheimer’s disease. But there are other, surprising warning signs that your brain health is at risk. Be on the lookout for these lesser-known symptoms, and call a healthcare provider if you suspect you or a loved one might be developing the disorder.

Sources: Li L, Zhang Q, et al. Tooth loss and the... + 21
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  3. National Institute on Aging. Tooth loss in older adults linked to higher risk of dementia. October 5, 2021.
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  9. Howard C, Mukadam N, et al. The effects of sleep duration on the risk of dementia incidence in short and long follow-up studies: A systematic review and meta-analysis. Sleep Med. 2024 Dec;124:522-530.
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  11. Liang Y, Qu LB, et al. Non-linear associations between sleep duration and the risks of mild cognitive impairment/dementia and cognitive decline: a dose-response meta-analysis of observational studies. Aging Clin Exp Res. 2019 Mar;31(3):309-320.
  12. Northwestern Medicine. Primary Progressive Aphasia. Accessed August 4, 2025.
  13. Emory University. Signs of a Normal Aging Mind. Accessed August 4, 2025.
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  18. Pacyna RR, Han SD, et al. Rapid olfactory decline during aging predicts dementia and GMV loss in AD brain regions. Alzheimers Dement. 2023 Apr;19(4):1479-1490.
  19. Dintica CS, Marseglia A, et al. Impaired olfaction is associated with cognitive decline and neurodegeneration in the brain. Neurology. 2019 Feb 12;92(7):e700-e709.
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  22. Parkinson's Foundation. 10 Early Signs of Parkinson's Disease. 2022. Accessed June 3, 2022.
Written by Patrick Sullivan.
Medically reviewed by Megan Burke, MD.August, 2025
Updated onAugust, 2026
Written by Patrick Sullivan.
Medically reviewed by Megan Burke, MD.August, 2025
Updated onAugust, 2026
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