Night owls are more at risk for dementia — but not for the reasons you might think

Alarming new evidence suggests that it may be unwise to be a night owl.

Research has indicated that nocturnal creatures face an increased risk of premature death.

A fresh study out of the Netherlands proposes that night owls may experience cognitive decline faster than early birds — but not because of their sleep times.

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“The good news is that you can partly influence this cognitive decline by adjusting your behavior,” said Ana Wenzler, a dementia researcher at the University of Groningen.

Dementia — a decrease in memory, language, reasoning and problem-solving skills — is a growing problem in the US. The number of new US dementia cases is projected to jump from about 514,000 in 2020 to around 1 million in 2060.

High blood pressure, physical inactivity and social isolation are among the factors that increase the risk of dementia.

Wenzler’s team wanted to see whether an earlier or later sleep-wake schedule played a role in this risk.

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About 40% of the global population are what’s known as morning “larks,” 30% are believed to be evening types, and the rest fall somewhere in between.

Wenzler analyzed nearly 23,800 sleep survey responses as part of a large Netherlands study, finding that only 5% of participants were night owls.

“Children are morning people. That changes when you reach puberty, when you become an evening person,” Wenzler noted.

“Around your 20s, that gradually shifts back toward morning people for most people,” she continued. “By the age of 40, most people are morning people again. But this is certainly not the case for everyone. In this way, evening people deviate from the norm.”

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Armed with everyone’s chronotypes, Wenzler compared the participants’ cognitive function test results over 10 years.

She determined that moonlight movers cognitively decline faster than sunrise starters.

The reason? Unhealthy behaviors such as smoking, drinking and poor eating occur more often in the evening.

“Evening people smoke and drink more often and exercise less,” Wenzler said. “Twenty-five percent of the risk of cognitive decline can be explained from our research by smoking and poor sleep.”

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This effect was more pronounced in highly educated people.

“That probably has to do with their sleep rhythm,” Wenzler explained. “They are often people who have to go back to work early in the morning and are therefore more likely to sleep too short, giving their brains too little rest.”

Unfortunately, Wenzler said it’s hard to adjust your biological clock and related sleep patterns.

“You can try to go to sleep earlier, but if your body is not yet producing melatonin,” she said, “it will not work: your body simply does not want to sleep yet.”

She suggests leaning into your preferred sleep style, and if that happens to be midnight madness, try to make healthy lifestyle choices to offset it.

These findings were published recently in the Journal of Prevention of Alzheimer’s Disease.

Wenzler plans to further investigate the relationship between night owls, faster cognitive decline in middle age and dementia.

“This will ultimately help us to be able to give people informed advice on how to try to prevent dementia,” she said.