Perhaps, one of the most commonly ingested chemical substances in the world today is caffeine. Caffeine is not only found in coffee but also in other popular beverages such as tea and soft drinks, in chocolate or cocoa-containing products, and in some drugs. Its wide consumption in all levels of population has led to a collective interest among the general public and the medical community over its possible adverse effects on our health.

Based on comprehensive published human studies, a moderate daily caffeine intake of up to 400 mg a day in the healthy adult population is not linked with any adverse effects like general toxicity, effects on bone status and calcium balance, cardiovascular effects, changes in behavior, and increased incidence of cancer.

Caffeine, once taken in by drinking a cup of coffee, cola, or tea, can affect all body systems because it is distributed throughout our body. However, contrary to common belief, the effects of caffeine are temporary and momentary because it does not accumulate in the body. Its physiological effects vary from person to person and normally depend on a number of factors. Regular coffee drinkers are less sensitive to the stimulant effects compared to others. Caffeine may stay in the body of pregnant women thrice as long as the usual adult, which explains why women feel more sensitive to coffee in the last trimester of pregnancy. Heavy smokers, on the other hand, eliminate caffeine twice as fast as non-smokers, which explains why some heavy smokers are also heavy coffee drinkers.

The best known physiological effect of coffee (caffeine) is that it is a nervous system stimulant. Caffeine relieves fatigue, increases alertness and concentration, and restores deteriorating performance. In some sensitive individuals, caffeine delays sleep, lowers quality of sleep, and decreases sleeping time. Caffeine’s effect on mood ranges from pleasing stimulation and mood elevation to irritability, nervousness, and anxiety. However, these effects are dose-related and short-lived.

Other short term effects of caffeine are increase in heart rate, blood pressure, plasma renin, plasma catecholamines and serum free fatty acids. Urine and gastric acid production also increases. Some people experiencing irregular heartbeat syndromes may opt to drink decaffeinated coffee since caffeine is known to precipitate ventricular premature beats or arrhythmias, as do alcohol, many drugs, stress, and exercise. Normal individuals who have regular consumption of coffee develop tolerance to these effects. Coffee and other caffeine-containing beverages are not linked with cardiovascular diseases, any kind of cancer, benign breast disease, or damage to fetus.

The popularity of coffee has increased tremendously over the new millennium. Coffee house companies like the infamous Starbucks Coffee continue to mushroom and develop their own signature preparation to entice the coffee-drinking public. The wide variety of concoctions of this beverage, from the traditional brewed coffee to the hot and cold espresso-based variations, make coffee drinking a pleasurable experience for both the young and young-at-heart. But back in the olden days in Muslim Arabia, the Koran forbade drinking coffee because it produces a kind of stimulation similar to that produced by liquor.

Perhaps the most popular notion about the effect of coffee to us is that it makes us alert and keeps us awake. Coffee is considered as central nervous system stimulant. Caffeine, the primary active chemical in coffee, is responsible for this action. It inhibits the action of the chemical known as adenosine, which naturally makes us drowsy; hence there is an increase in the speed of reaction and concentration. However when the transient stimulation ends, a sudden sluggishness follows and the brain cells will start needing caffeine for stimulation.

Coffee does not actually prevent sleep but only delays the need for sleep by relieving fatigue. It is for this reason that large quantities of coffee are consumed by people who are under heavy mental or physical strains or those who work for long hours. Stimulation brought about by coffee only lasts about two hours. Afterwhich, the same sluggish feeling before taking coffee sets in.

A series of experiments was conducted at the University of Chicago to test the effect of caffeine on sleep. Volunteers were grouped into two. The first group was given several ounces of coffee before bedtime while the second group was given a corresponding amount of milk. People under the first group were sure that coffee has caused a disturbance to their sleep while those under the second group did not make any similar complaint. Unbeknownst to these volunteers, the coffee given to the first group was decaffeinated while caffeine was added to the milk given to those under the second group. The experiment confirms that the sleep fallacy associated with coffee is largely psychological.

Another big misconception associated with coffee because of its active chemical, caffeine, is that it can kill you. Caffeine in small amounts is a stimulant and causes uncontrolled and irregular heartbeats which consequently lead to heart attack. This alkaloid is synthesized by the coffee plant with the purpose of killing its natural consumer or grazer. Just like any other drug, coffee must be taken moderately. It takes more than 400 mg of caffeine or 4 to 5 cups of brewed coffee to cause caffeine intoxication. It would take 80 to 100 cups of coffee drank very quickly to cause death in humans. So far no case of death caused by coffee drinking has been reported yet.

In terms of its cultural history, coffee is one of the greatest mysteries. Although it is known that the coffee bush grows wild throughout the highlands of Africa and that it may possibly be indigenous to Arabia, there is actually no evidence that coffee was used by the people in ancient Rome, Greece, Africa, or Middle East.

The myth of the Ethiopian goatherd, Kaldi and his dancing, goats is the most frequently encountered coffee origin story in Western literature. It strengthens the tradition that the first coffee encounter by the Sufi happened in Ethiopia.

The story says that Kaldi and his flock noticed the energizing effects of nibbling these bright red berries. These berries grow on a glossy green bush with a distinct fragrance. This account tells us that Kaldi chewed on the fruit himself and the experience made him go to a nearby monastery to tell the news of his discovery. The Islamic holy man rejected the idea and threw the fruit on fire, which only made the enticing coffee aroma more noticeable. The burnt beans were quickly collected from the embers, and were ground, and dissolved in hot water. This produced the first cup of coffee in the world. Sadly, Kaldi is just a myth and is not in any early Arab literature. He must, therefore, be some kind of imaginary character brewed over a cup of coffee.

This story reflects the logical supposition that Ethiopians, the origins of the Galla tribe, were the first to recognize the revitalizing effect of coffee. According to the theory, the Galla tribe gathered ripe cherries from wild trees, ground them up in mortars, and mixed the seeds with animal fat. This will make small balls that the tribe will carry for rations on war gatherings.

The flesh of the coffee fruit is rich in sugar, caffeine, and fat. It is also about fifteen percent protein, which gave solution to the problems of exhaustion and hunger of the Galla warriors. Other tribes of Africa are said to have made the coffee fruit into porridge or fermented it into wine.

Even without the assistance of early records, the plants’ prevalence across Africa will prove that coffee was under cultivation or growing wild all throughout that continent.

However, in Arabia, the coffee bean has been known as a stimulant since the time of the great astronomer and physician, Abu Bakr Muhammad ibn Zakariya El Razi. He called the beans “Rhazes” in his works, and might be the first written record of them. Across the Abyssinia, “Rhazes” refers to the coffee fruit and drink today.