Most of us have the odd bad dream. But if you’re regularly waking in a cold sweat, you might be wondering: is it just stress, or something more serious?
Some recent research has made headlines by linking frequent nightmares to an increased risk of dementia.
A 2022 study published in The Lancet eClinicalMedicine found that people in midlife who reported weekly bad dreams were more likely to experience cognitive decline.
Older adults with frequent nightmares were also more likely to go on to develop dementia. That sounds worrying – but should we really be alarmed?
Not necessarily. The study shows a correlation, but not causation. It’s unclear whether nightmares are an early symptom of changes already happening in the brain, or whether disrupted sleep somehow contributes to the disease process.
Other explanations are possible too – for example, people with anxiety, depression or poor sleep (which are themselves linked to increased dementia risk) are also more likely to have bad dreams.
All we really know for sure is that sleep plays a vital role in brain health. And there’s some evidence that regularly disrupted or poor-quality sleep, whatever the cause, may increase the long-term risk of developing cognitive disorders.
The bottom line? Regular nightmares alone aren’t a reliable early warning sign of Alzheimer’s.
For now, sleep hygiene remains the best first step, not just for sweet dreams, but for a healthy brain too. Stick to a regular bedtime, reduce caffeine and alcohol, and try to limit screens before bed.
This article is an answer to the question (asked by Aaron Martin, Stoke-on-Trent) ‘I keep having nightmares. Should I be worried?’
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