It is a myth that caffeine in coffee gives you energy. In reality it just gives you chemical stimulation. The perceived ‘energy’ comes from the body’s struggle to adapt to increased blood levels of stress hormones. While there is a short-term ‘lift’, caffeine’s ultimate effect is a letdown.
Below, various experts talk about what caffeine is actually doing to your body:
Within five minutes after you drink your morning coffee, the caffeine begins to stimulate your central nervous system, triggering the release of stress hormones in your body, causing a stress (“fight or flight” ) response. …if you are simply sitting at your desk you may feel a short charge of alertness, quickly followed by feelings of agitation. Within the next hour or so, after the stress response dissipates, you will probably feel more tired and hungry. At these low-energy times, many people reach for another cup of coffee, or eat a snack that is often high in sugar to “pep up” and stay alert. However, both caffeine and sugar only give you temporary feelings of increased energy, which quickly dissipate. For some people, this cycle of low energy followed by an infusion of caffeine or food continues the entire day.
Caffeine increases the stimulating neurohormone, noradrenaline, and reduces the calming neurotransmitter, serotonin.
A dosage of 50 to 100 mg caffeine, the amount in one cup of coffee, will produce a temporary increase in mental clarity and energy levels while simultaneously reducing drowsiness. It also improves muscular-coordinated work activity, such as typing. Through its CNS stimulation, caffeine increases brain activity; however, it also stimulates the cardiovascular system, raising blood pressure and heart rate. It generally speeds up our body by increasing our basal metabolic rate (BMR), which burns more calories. Initially, caffeine may lower blood sugar; however, this can lead to increased hunger or cravings for sweets. After adrenal stimulation, blood sugar rises again. Caffeine also increases respiratory rates, and for people with tight airways, it can open breathing passages. Caffeine is also a diuretic and a mild laxative.
Although we think of caffeine in coffee as the “wake-me-up” chemical, chronic use of it may cause fatigue, headache, moodiness, and depression in some people. Because caffeine boosts energy through increasing the production of ATP, the basic unit of energy production in your body, one school of thought suggests that chronically stimulating this system may deplete it, sort of like overworking the soil in farmland.
Caffeine can have a detrimental effect on blood sugar. When caffeine is ingested, the nervous system is stimulated. Adrenaline is released and, in turn, the liver begins to emit stored blood sugar. Insulin is then released, and blood sugar drops below normal—a common seizure trigger for people with epilepsy.
Watch out for coffee. The caffeine in coffee can upset blood-sugar levels, leaving you fatigued and longing for a quick-pick-me-up snack.
Caffeine doesn’t add energy to your system, it just burns up your reserves at a faster pace. You get a short-term boost at the expense of long-term jitters and fatigue.