More than a sunny disposition could lower dementia risk.
Upwards of 6 million Americans live with dementia, a number that’s expected to double by 2060 with aging populations and rising cases of conditions like obesity that are linked to cognitive decline.
Several lifestyle choices, like exercise, avoiding smoking and listening to music, can all lower dementia risk, as well as one incredibly easy habit you may already be doing.
A study published in General Psychiatry suggests that not getting enough sunlight could mess with brain function as we get older — but soaking up the sun, even for a little bit, has benefits.
Researchers tracked nearly 90,000 dementia-free participants’ daylight exposure for a week, then compared the findings over eight years with participants who developed dementia.
Those who got around 42 minutes of bright daylight per day were about 17% less likely to develop dementia than people who received less sunlight.
The connection remained even after the researchers accounted for factors that affect the chances of dementia, such as diet, obesity, physical activity and heart health.
The effect of light on the brain may be due to our circadian rhythm, which is activated when light enters the eyes and maintains the body’s sleep-wake cycles, support immune function, fight inflammation and more.
When we get more restorative sleep, the brain can undergo necessary cellular maintenance and remove metabolic waste, an essential step to lessen the chances of cognitive problems in the future.
And according to one psychologist, sunlight isn’t the only type of light that affects brain health.
“We are beginning to recognize that our brains and bodies are profoundly influenced by environmental signals, including light, that regulate fundamental biological processes,” board-certified neurologist David Perlmutter, who wasn’t involved with the study, told Prevention.
Beyond the sun, we’re exposed to all kinds of light, from sunrise alarm clocks to blue light emitted from our phone and laptop screens.
And while healthy habits like stress management and social connections help maintain cognitive skills as we get older, Perlmutter says natural light should be part of the conversation around dementia.
The study also found the connection between daytime light and reduced risk of dementia was even stronger in those with the APOE4 gene variant — which increases risk for Alzheimer’s disease — a “particularly fascinating finding,” according to Perlmutter.
“Our genes influence our susceptibility, but our daily choices and environmental exposures can profoundly influence how that susceptibility plays out,” he added.
There are a number of health experts — and biohackers — who swear by sunlight exposure early in the morning for various health benefits.
Researchers in central Europe published a study earlier this year finding that consistent exposure to natural light led to “more stable blood glucose levels and an overall improvement” in the metabolic profile of all 13 volunteers who participated in their study.
If getting sunlight during the darkest days of winter is difficult, a light therapy lamp may do the trick to mimic sunlight, although there’s no research on whether they can prevent dementia.
