For many people, coffee is an essential part of the day, especially in the morning. However, health experts often recommend limiting caffeine intake to earlier hours, typically before mid-afternoon. The reason goes beyond simply struggling to fall asleep — late-day coffee consumption can interfere with the overall quality of sleep and the body’s recovery process.
Dr Kunal Sood, an anaesthesiologist and interventional pain specialist, recently explained how drinking coffee later in the day affects the body. He highlighted that caffeine can push the brain into a heightened state of alertness at a time when it should be preparing for rest. This not only delays sleep but also disrupts the natural rhythm of the body.
Caffeine works by blocking adenosine receptors in the brain. Adenosine is responsible for building sleep pressure, helping you feel tired as the day progresses. When caffeine interferes with this process, it becomes harder for the brain to recognize when it is time to sleep. Since caffeine can remain active in the body for more than six hours, even an afternoon cup can impact bedtime.
Another important concern is the reduction in deep sleep. Deep sleep, also known as slow-wave sleep, is the most restorative stage and is essential for physical and mental recovery. When caffeine levels are elevated, the body spends less time in this stage and more time in lighter sleep phases, reducing overall restfulness.
In addition to this, caffeine can increase nighttime awakenings. It stimulates the nervous system and keeps the body in a semi-alert mode, making sleep more fragmented. This means even if you spend enough hours in bed, the sleep may not be continuous or refreshing.
Caffeine also triggers the release of cortisol, the body’s stress hormone. Elevated cortisol levels in the evening can further delay sleep and make it difficult to maintain a consistent sleep cycle.
As a result, even after what seems like a full night’s sleep, individuals may wake up feeling tired and rely on more caffeine the next day, creating a cycle of poor sleep and dependency.
Experts suggest being mindful of caffeine timing and limiting intake to earlier in the day to maintain better sleep health and overall well-being.