Tengrinews.kz - Many of us are used to drinking coffee throughout the day to stay alert and productive. However, according to some studies, coffee in the afternoon can be very detrimental to the quality of sleep and overall well-being.
How caffeine disrupts your sleep-wake cycle
Caffeine is one of the most powerful natural stimulants of the central nervous system. Its main function is to block adenosine, a substance that accumulates in the brain during the day and causes a feeling of fatigue. As a result, the brain continues to remain active even at times when the body already needs to rest.
According to a review by Professor Renata Riha, from the Department of Sleep Medicine at the University of Edinburgh on the News-Medical platform, the half-life of caffeine in the body is between 3 and 7 hours. This means that a cup of coffee drunk at 3 PM could continue to affect your brain even at 9 PM, which could disrupt your natural sleep processes.
The effect of coffee on the biological clock
An important component of sleep quality is the hormone melatonin, which is produced during the dark hours of the day and helps the body fall asleep. Caffeine suppresses the production of melatonin, which can shift the natural circadian rhythm.
The study showed that drinking coffee six hours before sleep reduces its total duration by an average of 1 hour. This is due to the fact that the brain remains in a state of increased activity, despite the body's desire to rest. Disruption of circadian rhythms can lead to chronic sleep deprivation, which is fraught with deterioration of cognitive abilities, decreased immunity and increased stress levels.
Why coffee after lunch is dangerous
Drinking coffee in the afternoon can cause a "shift" in the body's biological clock. This is especially true for those who work shifts or have an irregular sleep schedule. In such cases, caffeine can make it difficult to fall asleep, even if the person is physically tired.
Professor Riha's review highlights that frequent sleep disturbances can increase the risks of:
obesity;
type 2 diabetes;
cardiovascular disease.
According to the study, this is due to a disruption in the hormonal balance that is responsible for appetite control. People who experience chronic sleep deprivation are more likely to overeat and consume high-calorie foods.
Individual sensitivity to caffeine
The effect of caffeine on the body depends on the genetic characteristics of metabolism. Some people process caffeine more slowly, which is why its effects on the body are felt much longer. For others, it is broken down more quickly, and they can safely drink coffee even before bedtime without obvious consequences for sleep.
However, the study emphasizes that even in people with a "fast" metabolism, caffeine can negatively affect the quality of sleep, especially if consumed in large quantities.
What to do to improve the quality of sleep
To avoid the negative impact of caffeine on sleep, experts recommend:
Do not drink coffee after 2-3 PM. This will allow the body to process the caffeine before bedtime.
Limit the amount of caffeine. Drink no more than 2-3 cups a day.
Monitor the time of coffee consumption. If you feel tired in the afternoon, it is better to do exercises or get some fresh air.
Warning!
Before making changes to your eating habits, including coffee or other beverages in your diet, you should consult with your doctor or nutritionist. Individual characteristics of the body may require a special approach to caffeine consumption.
Related links:
New study reviews effect of coffee on people's sleep and wake cycles
About the study:
The study was conducted by Professor Renata Riha, from the Department of Sleep Medicine at the University of Edinburgh. The work was published on the News-Medical platform on February 4, 2021. The review examined the results of numerous scientific studies on the effects of caffeine on circadian rhythms, melatonin production, and sleep quality.
