Chronic Insomnia: Not Just Counting Sheep, But Killing Them Off One by One

Wednesday, October 1, 2025.

Insomnia has always been the punchline of late-night infomercials and sad jokes about 3 a.m. bowls of cereal.

But according to a new study in Neurology, the consequences are more serious than bleary mornings.

Chronic insomnia, it turns out, is linked to faster memory loss, cognitive decline, and brains that age as if they’ve been running a 24-hour diner (Carvalho et al., 2025).

The researchers didn’t just hand out surveys and call it a day.

They pulled from the Mayo Clinic’s long-term Study of Aging, tracking 2,750 adults over 50.

Of these, 443 had chronic insomnia; the rest presumably slept like people who don’t worry about whether their ex secretly hates them.

Everyone got tested — memory, language, problem-solving, spatial skills — and some were lucky enough to be shoved into giant, humming machines for brain scans.

What They Found (and Why You Should Care)

• People with chronic insomnia had a 40% higher risk of developing mild cognitive impairment or dementia (Carvalho et al., 2025).

• The risk was the equivalent of aging an extra 3.5 years. Congratulations, your restless nights have gifted you an honorary AARP card.

• Insomnia plus short sleep duration (the double whammy) showed even worse outcomes: more white matter damage and higher levels of amyloid plaques, those sticky little proteins that scream Alzheimer’s ahead.

For perspective, the effect of poor sleep on amyloid buildup was comparable to carrying the infamous APOE e4 gene — which is science-speak for “your DNA is trying to kill you, and so is your insomnia.”

It’s Not Just About Feeling Groggy

The study suggests that insomnia isn’t merely about being cranky or drinking too much coffee. It’s about your brain’s plumbing and wiring. White matter hyperintensities — those charming little brain lesions — showed up more in the insomniac group, pointing toward blood vessel trouble.

Meanwhile, amyloid plaques stacked up like junk mail, suggesting a head start on Alzheimer’s pathology (Carvalho et al., 2025).

This lines up with earlier research linking poor sleep quality to increased beta-amyloid burden (Ju et al., 2013) and small vessel disease (van Dijk et al., 2012).

What About Sleeping Pills?

Before you throw your Ambien in the trash, good news: hypnotic medications weren’t linked to faster decline in this study (Carvalho et al., 2025). That doesn’t mean they’re a miracle cure — just that they weren’t the villain here. For now, your brain’s worst enemy is still itself.

Limitations (Because Science Is Never That Simple)

• Insomnia diagnoses were pulled from medical records, not gold-standard sleep interviews.

• Sleep duration was self-reported. Translation: people guessed.

• The participants were mostly white Minnesotans, which means we don’t know how insomnia plays out in, say, Black or Latino communities, or frankly, anyone who doesn’t live within driving distance of a snowmobile dealership.

Why This Matters

This research adds to a growing pile of evidence that sleep is not a luxury — it’s actually scaffolding for your brain.

You can meditate, eat kale, do puzzles until your eyes bleed. But if you’re lying awake night after night, your neurons are basically whispering, we can’t keep this shit up forever.

Therapists and sleep experts already tout cognitive behavioral therapy for insomnia (CBT-I) as the gold standard, and these findings reinforce why: it’s not just about surviving the next day, it’s about preserving the next decade (Trauer et al., 2015).

Closing Thought

Insomnia doesn’t just ruin tomorrow’s mood; it speeds up the expiration date on your brain.

The study doesn’t prove insomnia causes dementia, but the association is strong enough that if you’re tossing and turning nightly, it may be time to stop joking about it and start treating it. Because in the end, sleep isn’t about rest — it’s about brain resilience.

Be Well, Stay Kind, and Godspeed.

REFERENCES:

Carvalho, D. Z., Kolla, B. P., McCarter, S. J., St. Louis, E. K., Machulda, M. M., Przybelski, S. A., … Vemuri, P. (2025). Associations of chronic insomnia, longitudinal cognitive outcomes, amyloid-PET, and white matter changes in cognitively normal older adults. Neurology. https://doi.org/10.1212/WNL.0000000000212345

Ju, Y. S., Lucey, B. P., & Holtzman, D. M. (2013). Sleep and Alzheimer disease pathology — a bidirectional relationship. Nature Reviews Neurology, 10(2), 115–119. https://doi.org/10.1038/nrneurol.2013.269

Trauer, J. M., Qian, M. Y., Doyle, J. S., Rajaratnam, S. M. W., & Cunnington, D. (2015). Cognitive behavioral therapy for chronic insomnia: A systematic review and meta-analysis. Annals of Internal Medicine, 163(3), 191–204. https://doi.org/10.7326/M14-2841

van Dijk, E. J., Prins, N. D., Vrooman, H. A., Hofman, A., Koudstaal, P. J., & Breteler, M. M. (2012). Progression of cerebral small vessel disease in relation to risk factors and cognitive consequences: Rotterdam Scan Study. Stroke, 39(10), 2712–2719. https://doi.org/10.1161/STROKEAHA.107.507164