The Science of Sleep: Why We Need It and How to Get It
Why Sleep Matters
It is widely recognized that sleep is vital for overall health, yet about a third of Americans do not get enough rest. Science indicates that the optimal amount for adults is between seven and nine hours per night. Chronic under-sleep is linked to serious health risks, including:
• Increased rates of diabetes and heart disease
• Depression and immune suppression
• Weight gain
Furthermore, sleep deprivation has immediate effects on cognitive function, such as reduced reaction times—which, in studies, have been shown to be as impaired as being legally drunk—and increased sensitivity to pain and mood swings.
The Concept of Local Sleep
Traditional science viewed being awake and asleep as a binary state. However, new research suggests that our brains are more complex.
Local Sleep Phenomenon
When we are severely sleep-deprived, our brains may experience local sleep, where specific areas of the brain go "offline" and enter a sleep state even while we are technically awake. This explains why we may feel "spaced out" or function poorly when tired. Conversely, parasomnias—like sleepwalking—occur when the part of the brain responsible for specific actions wakes up while the rest of the brain remains asleep.
"Your brain is awake, so you're still doing stuff. But a part of your brain is kind of offline. It's doing its own thing. It's kind of asleep."
Evaluating Common Sleep Hacks
Many people turn to products to "hack" their biological clock, but the science behind these is often underwhelming:
• Melatonin: While it acts as a signal for the body to prepare for rest, studies show that, at best, it only helps people fall asleep about five minutes faster than a placebo.
• Blue Light: The hype around blue light from electronic devices having a major impact on sleep is largely overstated. Research suggests the act of engaging with content on your phone (work, social media) is more likely to keep you up than the light itself.
Instead of relying on quick fixes, experts recommend building a personalized sleep routine—such as keeping a cool room, using a sound machine, and ensuring consistent wake-up times—to defend your rest.