Next time you step outside at night, take a moment to look around. Notice how the stars are barely visible and how the glow from streetlights and buildings washes out the sky. If you live in a big city, this might feel normal, but it wasn’t always like this. That artificial light is causing more harm than you might realize. 

Light pollution is creeping into every corner of the world, and it's not just messing with our ability to stargaze—it’s also disrupting our sleep, health, and ecosystems. And, of course, it’s only getting worse. 

What is Light Pollution? 

Electricity is a beautiful thing—it keeps us safe and warm, lights our homes, and powers our appliances. However, like carbon dioxide emissions and plastic waste, too much of a good thing can negatively impact the environment. Light pollution refers to excessive or misdirected artificial lighting that brightens the night sky and affects our ability to see the stars. It has worsened as cities and urban areas expand. Streetlights, billboards, and even the light spilling out from your neighbor’s window all contributes to an artificial glow that disrupts natural darkness. 

In the U.S., this issue is widespread. About 80% of Americans live in areas where they can't see the Milky Way due to light pollution.  

How Does Light Pollution Affect Humans? 

Artificial light, especially at night, interferes with our body’s natural circadian rhythm—the internal clock that regulates sleep and wakefulness. Our bodies are wired to follow the natural cycle of day and night, but constant exposure to artificial light throws us off track. 

When we’re exposed to artificial light, particularly blue light from LED screens or streetlights, our brains interpret it as daytime. This suppresses melatonin production, the hormone responsible for sleep. Without enough melatonin, we stay awake longer than we should, leading to poor-quality sleep, insomnia, and an increased risk of health problems. Disrupted circadian rhythms have been linked to sleep disorders, obesity, heart disease, and even certain cancers. 

Additionally, lack of sleep affects mental health. Sleep-deprived individuals struggle with focus, experience heightened stress, and often find it harder to be productive. We live in a world that never truly sleeps—while New York City claims that nickname, most urban areas feel the same pressure. Even in the middle of the night, artificial lighting keeps darkness at bay

What About Animals? 

Light pollution isn’t just a human problem—it’s affecting wildlife in ways we’re only beginning to understand. For many species, the natural rhythms of day and night are essential for survival, and artificial lights throw these rhythms into chaos. 

Take sea turtles, for example. After hatching on beaches, baby turtles instinctively head toward the ocean by following the moon’s natural light. But in areas with heavy coastal development, artificial lights confuse them, leading them in the wrong direction—straight toward danger instead of the safety of the water. This disorientation contributes to declining sea turtle populations. 

Migratory birds also suffer. Many species rely on the night sky for navigation, but artificial lights from buildings and streetlights disorient them, causing them to veer off course. Some even fly directly into buildings, unable to navigate properly. This disruption affects not just migration patterns but also breeding and feeding habits. 

Insects, particularly nocturnal species like moths, are also drawn to artificial lights, becoming disoriented, fatigued, or trapped. This disturbs their natural behaviors and has ripple effects throughout ecosystems, as insects are a crucial food source for many animals. 

The Global Scope of the Problem 

While light pollution is a major issue in the U.S., it’s also a global problem. Cities across Europe, Asia, and beyond are also experiencing the negative effects of excessive lighting. A 2016 study found that about a quarter of the global population lives in areas where they can’t see the Milky Way due to light pollution. Millions of people are missing out on the beauty of the natural night sky. 

Even rural areas, once untouched by light pollution, are now seeing the glow of nearby urban centers creeping into their night skies. As cities expand, light pollution spreads, threatening the last remaining pockets of natural darkness. 

The consequences extend beyond human enjoyment of the stars. Ecosystems, plant life, and wildlife are all affected. Plants rely on natural light cycles to determine when to bloom, and artificial light can disrupt these cycles, affecting growth and reproduction. This, in turn, impacts the entire food chain. 

How LEDs Could Help Solve the Problem 

Now for some good news—while LED lighting contributes to light pollution, it can also be part of the solution if used correctly. LEDs are energy-efficient and can be directed where light is needed most, reducing unnecessary light spill. When properly implemented, LEDs can cut down on light pollution while still providing sufficient illumination for streets and public spaces. 

Additionally, LEDs can be customized to emit less blue light, which is particularly disruptive to human circadian rhythms. By switching to warmer LED lights or using dimming systems, we can mitigate the impact on both people and wildlife. 

There’s also a growing movement advocating for “dark sky” initiatives. These efforts focus on reducing light pollution through better lighting design, such as shielding lights, using timers, and dimming streetlights when not needed. Cities like Flagstaff, Arizona, and parts of Europe are leading the way in creating light-pollution-free zones where residents can experience the night sky as nature intended. 

What Can You Do? 

You might be wondering how you can help reduce light pollution. While it’s a global issue, small individual actions can make a difference. Start by reducing unnecessary lighting in and around your home. Use energy-efficient LED bulbs with a warmer color temperature and ensure outdoor lights are shielded to prevent light spill. 

If you live in an urban area, advocate for better city lighting policies. Support dark sky initiatives and encourage the use of more efficient, less intrusive lighting to protect both human health and the environment. 

Lastly, take time to enjoy the natural night sky when possible. Whether in a city or a rural area, stargazing is a great way to appreciate the universe’s beauty and remind ourselves why preserving the night is important. 

Final Thoughts 

Light pollution is more than just an inconvenience—it’s a serious issue that affects human health, disrupts ecosystems, and limits our connection to the natural world. By understanding the problem and embracing solutions like LED technology and better lighting design, we can reduce light pollution and protect both people and wildlife. 

The next time you look up at the stars, think about the impact of light pollution and how small changes can make a big difference. The night sky is waiting—let’s ensure it remains visible for future generations.