A Daily Dose of Sunshine Keeps Your Body Clock Running Smoothly

There’s nothing like a sunny day to put a smile on your face and a spring in your step. But turning your face to the sun does much than just feel good. It impacts virtually every cell in the body by helping to keep essential circadian rhythms running smoothly.

Like other life forms, humans depend on a 24-hour cycle of mental, physical and behavioral changes to stay healthy and functional. The rhythms are regulated by clock genes—molecules present in virtually all our organs and tissues. They enable our bodies to alternate periods of activity and rest. A master clock, located in the brain, keeps circadian rhythms regular by responding to light and darkness.

In the morning, light enters our eyes and helps us feel energized and alert, while nightfall brings a craving for restful sleep. In the days before electric lights and televisions, computers and smartphones, human beings naturally wound down when the sun set and rose with the sun, as their circadian rhythms dictated.

But in a world where artificial lights fool our bodies into behaving as if we’re living in eternal sunshine, these rhythms and the hormones that control them can be thrown off-kilter. The results can range from mood and cardiovascular problems to eating and sleep disorders. Turns out, it isn’t nice to fool Mother Nature by upending the circadian rhythms that keep the body functioning efficiently.

One way people short-circuit their 24-hour clock is by watching television or using devices late into the evening. These emit blue light, which disrupts the brain hormone that nudges us to sleep. When this happens, you may have trouble thinking clearly and sleeping well, and your blood pressure and release of other hormones may be negatively affected.

Scientists have recently discovered that older people are less sensitive to light, which diminishes their ability to reset their circadian rhythms. This may explain why senior citizens often have trouble getting a good night’s sleep.

Older people also require more light to maintain a sufficient level of vitamin D, which the body produces when exposed to sunlight. A deficiency in the vitamin is linked to metabolic syndrome, which increases the risk for diabetes and cardiovascular problems. The natural aging process and a more house-bound lifestyle mean the elderly are more likely to be deficient.

Spending time in the sun may be worth a few more wrinkles, as long as you apply sunscreen to protect against skin cancer every time you venture outdoors. Research indicates regular exposure to natural light may lower systolic blood pressure, reduce the risk of multiple sclerosis and make it easier to maintain a healthy weight—as long as you get your dose of sunlight early in the day.

Other health benefits range from a lowered risk of bone fractures and improved sleep quality to better brain function. People with Alzheimer’s disease do better on mental exams and experience less depression, agitation and nighttime wakefulness when they’ve been exposed to bright light from 9 a.m. to 6 p.m., according to one study.

Scientists also have wondered whether sunlight might be therapeutic against COVID-19. While the jury is still out, evidence indicates that moderate exposure to sunlight may bolster the immune system. It’s perhaps noteworthy that before the development of antibiotics, conventional wisdom viewed sunshine as an effective treatment for a wide range of conditions. And current research indicates Spanish flu patients during the 1918 pandemic had lower death rates if they regularly spent time in fresh air and sunlight.

While artificial light also offers benefits, and is sometimes used therapeutically, some experts believe natural light is the gold standard for good health because it is more biologically effective –even on a cloudy day. Fifteen to 45 minutes outdoors should do the trick.

At Monarch Landing, you can enjoy your time in the sun by strolling the campus’s many paths or, during warmer months, wandering the Butterfly Garden. Even when icy temperatures keep you indoors, our light-filled rooms and apartments ensure that you will always get your daily dose of sunshine—and keep those circadian rhythms running smoothly.