What Happens When You Drift Off

Every night, nearly everyone around the world enters a state of unconsciousness and temporary paralysis, known as sleep. But what exactly happens within our bodies when we drift off, and what are the consequences if we don’t get enough rest?

Sleep is governed by our circadian rhythm, often referred to as the body’s internal clock. This clock is located in the brain and is highly responsive to light. When it gets dark, the body clock triggers the production of melatonin, a hormone that promotes sleep. As morning approaches and light increases, melatonin production slows down, helping us wake up.

Sleep unfolds in four stages that repeat in cycles throughout the night. On a typical night, these cycles occur four or five times.

• Stages 1 and 2: These are light sleep phases, marking the transition from wakefulness to sleep. During these stages, heart rate and breathing slow down, body temperature drops, and muscles may twitch.

• Stage 3: Known as deep sleep or “Delta sleep” due to the slow delta brainwaves that dominate this stage, this is when the body undergoes significant repair. Cells produce the most growth hormones here, helping to heal bones and muscles.

• Stage 4: This is the stage where dreaming occurs. The brain is highly active, and your eyes move rapidly behind closed lids, known as REM (Rapid Eye Movement) sleep. During this phase, the body releases chemicals that induce temporary paralysis, preventing us from acting out our dreams.

On average, humans spend about one-third of their lives asleep. However, modern lifestyles, stress, and the widespread use of technology have led to people sleeping much less than they did a century ago. Regularly getting less than seven hours of sleep per night is linked to an increased risk of developing chronic health conditions, potentially shortening life expectancy.

For a healthier, longer life, make sure to prioritize your sleep.