Mental Health

Artificial Light at Night: A Health Warning

When the sun sets, the human body is designed to begin a remarkable transformation. Hormones shift, body temperature gradually falls, and the brain prepares...

imtiaz 5 min read · 4 weeks ago

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When the sun sets, the human body is designed to begin a remarkable transformation. Hormones shift, body temperature gradually falls, and the brain prepares for one of the most important biological processes—sleep. For thousands of years, this natural rhythm was guided by daylight and darkness. Today, however, the night is no longer truly dark.

From smartphones and laptops to LED streetlights and brightly lit homes, artificial light has become an unavoidable part of modern life. While these innovations have improved convenience and productivity, researchers are increasingly discovering that excessive exposure to light after sunset may come with hidden health costs.

Your Body Runs on an Internal Clock

Deep inside the brain is a tiny region called the suprachiasmatic nucleus (SCN), often referred to as the body's master clock. This internal clock regulates the circadian rhythm—a roughly 24-hour cycle that influences sleep, hormone production, metabolism, body temperature, and even immune function.

Natural sunlight tells the brain it is time to stay awake and alert. As darkness arrives, the brain begins producing melatonin, a hormone that signals the body to prepare for sleep. This process has evolved over millions of years and plays a critical role in maintaining physical and mental health.