Caffeine is a known stimulant which elevates the heart rate and blood pressure and acts as a booster for energy levels and the overall mood of a human being. Many people are addicted to caffeine and their day cannot just begin without a cup of coffee. This magic stimulant provides instant energy as it is readily absorbed in the body through the lining of the mouth, throat, and stomach and it has the ability to easily enter the bloodstream providing instant results.
The science behind caffeine perks and its decline
The effects of caffeine can vary from person to person as with any drug consumption, the time of how quickly it metabolizes in the body can be different for everybody. Usually, it takes only a matter of 15 to 45 minutes of 99% of the caffeine to get absorbed in the body through the lining membranes of the mouth and raise the levels of caffeine in the body.
Caffeine has a half-life of 4 to 6 hours on average in humans, which means that someone who consumes 40 mg of caffeine will have 20 mg remaining in their bloodstream after those 4 to 6 hours. After this time, caffeine is quickly metabolized by the liver, is broken down, hence decreasing its levels in the body. Thus, caffeine does not last in the body for the whole day. Effects of caffeine and its half-life vary with age and people suffering from medical conditions.
Most people feel the perks of caffeine just after consumption and report its strongest effects like feeling jittery, need to urinate, and feeling a sudden boost of energy during this time. But as caffeine reaches its halftime period, these symptoms tend to fade away as the breakdown process starts in the liver.
Caffeine in the brain
The most studied amongst the effects of caffeine is the lasting of caffeine in the body. Caffeine is similar to the molecule adenosine in the brain. Adesonine is responsible for the sleep-wake cycle in the body. It binds to the receptor cells and signals the brain that it’s time to make you feel sleepy. Caffeine molecules bind to the receptors in the brain and block adesonine from binding to them so that signals of rest form the brain to the body can be prevented. Furthermore, when adesonine cannot bind to the receptors, its levels in the body increase giving rise to the release of adrenalin which is a stimulating hormone responsible for adding to the feelings of energy and alertness.
Build up of caffeine intolerance
As with all drugs, a time comes when the human body builds up resistance to the drugs consumed more often, similarly, people who consume several cups a day of coffee may barely note the difference. But, you are not used to that much coffee in a day, or you are sensitive to caffeine, the effects may last longer. Some people, who are not coffee lovers, often report of sleepless nights if they had had a cup just before going to bed.
And for people who just cannot live without caffeine in their body, too much caffeine can make you experience sleepless nights, or trouble falling asleep. How hard it hits you depends on the amount you are consuming, your age and weight. If you are overweight, you might notice that you require a higher intake to keep you awake or for giving you that energy boost.
When to have another cup of coffee?
When caffeine exits the body through urine, the person may experience feelings of tiredness and fatigue because of the elevated levels of adesonine. This may be the time for your next cup of coffee; that is if it is not yet the time for you to sleep!