Understanding Caffeine
Caffeine is one of the most misunderstood substances we consume. Far too many people believe caffeine is a straight shot of energy; that isn't entirely true.
Caffeine is a stimulant naturally found in coffee beans, but also tea, yerba mate, guarana, and kola nuts. At its core, caffeine tricks the body into thinking it's not as tired as it actually is. To understand how caffeine works its magic, we first have to recap how the body starts to feel sluggish.
The primary source of energy in the body is called ATP (adenosine triphosphate). When your body breaks down ATP, it releases adenosine. Adenosine is a chemical responsible for slowing down the body's functions. It is responsible for calming down the nervous system and, with time and accumulation, nulling us to sleep.
As you burn energy throughout the day, your brain begins to accumulate more and more adenosine. Eventually, with enough stored, you reach the point of no return and knock out. Caffeine loves to cause chaos.
Caffeine has a very similar molecular structure to adenosine, allowing it to trick the body into not feeling as tired as it should. Caffeine's structure allows it to bind to the receptor cells in the brain that adenosine usually binds to. As caffeine blocks these receptors from binding to adenosine, it slows down how quickly you will feel tired. Rather than calming the nervous system like adenosine, caffeine stimulates it, causing increases in heart rate, higher blood pressure, and greater alertness. Caffeine also promotes the effects of dopamine, the chemical that helps foster happiness.
However, the body is an ever-adapting work of wonders. If you drink a cup of coffee every single morning, as many of us do, there's a good chance it's just fool's gold. You see, as you build that habit of drinking coffee daily, your body gets fed up. The consistent dose of caffeine results in there being far too much adenosine just sitting around and doing nothing. Therefore, your brain actually creates MORE receptors for adenosine. Suddenly, one cup of coffee just doesn't do it anymore, and you find yourself reaching for more.
This is how your caffeine tolerance comes to fruition. The more often you consume caffeine, the less effective it's likely to be. To make matters worse, if you're a daily consumer, missing out on your cup of coffee could result in intense withdrawal. Remember, because regular consumers have more receptors than the average person that means without the caffeine, they'll absorb more adenosine too. Their withdrawal will bring about more significant fatigue than they would otherwise experience with caffeine in their diet. They are also subject to headaches and depressed moods, given that adenosine interferes with dopamine.
But there's nothing to panic about. The body will always favor homeostasis. Within a week or two of cutting off caffeine entirely, your brain eliminates those extra adenosine receptors, and things go back to normal. Caffeine will go back to being more effective, assuming you don't drink it too often, and your energy levels will improve.
Caffeine (milligrams)
Caffeine's effects peak about 30 minutes after consumption. It has a half-life of roughly 6 hours. Therefore, after 6 hours, you only feel about half of the effects and may be tempted to reach for your second cup. Remember, caffeine isn't much of an energy boost, but rather a fatigue delayer. This means that if you are already tired, and adenosine has already found its way to your brain, no amount of caffeine will undo your fatigue. The only way to truly cleanse your receptors of adenosine is through sleep!
It is highly recommended that you do not abuse your caffeine intake, for it's often linked to insomnia—for obvious reasons—and anxiety. Doctors recommend your daily consumption doesn't surpass 300 milligrams of caffeine per day.
