Although we feel safer sleeping in a well-lit neighborhood, light pollution may actually interfere with our circadian rhythm and rob us of high-quality rest.

The Western world has associated light with safety for over 100 years. Our streets and neighborhoods are filled with lights that help us to see and prevent danger. In many ways, this has made us safer than ever. However, these lights sometimes keep us from getting the sleep we need, which can cause a wide range of health problems.

Light Pollution in the Western World

The images from the International Space Station show a world lit up with artificial lights in the middle of the night—a testament to man’s triumph over nature. However, the ambient light from our cities and towns leads to a very modern kind of pollution: a lack of dark at a time when we need it most. Even when we feel that we are in the dark of night, we are bathed in light sensed by our brains. Recent chronobiology studies suggest that this may have an effect on our sleep and thus on our health.

Is Light Pollution Bad for Us

While a well-lit planet may feel safer, it actually may be a danger. 29 percent of people who live in well-lit areas feel that they are not getting adequate sleep, which can present health dangers. In fact, people in these areas are three times as likely to complain about sleep issues such as insomnia. Even if you cannot perceive the ambient light around you, it is present and may be interfering with your rest—and therefore with your health.

The Effects of Ambient Light

The ambient light from our well-lit cities has more of an effect than we realize. Even if you don’t notice the light that surrounds you, it can have an effect on your sleep and your well-being. Light is sensed by our retinas even when we do not consciously register it. The presence of light is passed onto the suprachiasmatic nucleus of our hypothalamus, which signals the pineal gland to halt production of melatonin. Because of the important role of melatonin in sleep, even ambient light can have an adverse effect on our sleep patterns.

Several diseases have been linked to a lack of quality sleep. These diseases are also on the rise in the modern world, from cancer to heart disease. While these diseases are not solely caused by a lack of quality sleep, they are certainly influenced by it. This means that the high levels of ambient light in the modern world could be contributing to a simultaneous increase in chronic disease.

Could reducing light pollution and creating dark spaces be the secret to good health? While there is no one secret to achieving a healthy, disease-free life, getting adequate sleep is very important to our physical and mental well-being. Although ambient light is not the only factor in the recent uptick in disease, it appears to be an important part of the equation.