It keeps you awake because it blocks a chemical that promotes sleep but does not stop its production
Some people who drink coffee regularly have developed caffeine tolerance.
In the morning you have your stimulating cup of coffee that prevents you from being somnolent and what do you keeps alert at work, but in the afternoon your productivity is not the same, you feel exhausted and sleepy again. The cause may be caffeine.
Caffeine can not only increase alertness and attention, it can also reduce anxiety and improve mood, according to the Harvard School of Public Health. So what’s going on?
Sleep chemical builds up
Caffeine at first it takes your sleep why It blocks adenosine (a chemical that makes you want to sleep) and the receptors in your brain.
Given the caffeine does not affect the production of this chemical, it only blocks. When the caffeine effect wears off, there is an accumulation of adenosine who wants to join their receivers. This can cause tiredness or drowsiness.
The body absorbs 99% of caffeine within 45 minutes of consuming it. The stimulating effects they can start between 15 and 30 minutes after ingestion, they last for about 4 hours on average.
Diuretic effects. While some people who drink coffee regularly and have developed caffeine tolerance, others have diuretic effects.
Frequent urination could dehydrate you, and one of the effects of dehydration is feeling tired.
If you usually add sugar. One of the negative effects is that quickly raises blood glucose levels and then comes a power drop. The worst thing is that your brain will ask for more sugar.
What to do?
Moderate consumption. Less than 400 mg per day, maximum 4 or 5 cups. An 8-ounce cup of coffee contains about 80 to 100 mg of caffeine.
Avoid adding creams and too much sugar to your coffee.
If you drink coffee too late in the afternoon you will block your sleep, but you could have trouble sleeping, so the next morning you will also be sleepy.