What do you do when you have a board presentation due in the morning and by the night before, you are yet to begin preparations for the project? Or as a student, you have an exam and you are yet to cover grounds in studying? How about what you would do if you had to attend to pressing matters after a night of poor sleep? For most people, a wake-me-up is the immediate line of action and the beverage of choice is coffee.
It is generally believed that a cup of coffee is a miracle mug of liquid energy. All that in needed is a cup or more, and there is immediate spike in alertness. The ingredient that does the trick is caffeine. Caffeine is considered a drug that stimulates the central nervous system and increases energy and alertness. There have also been reported cases of some people receiving a temporary boost in mood. While for some, the desired effect of a burst of energy is achieved, for others, drinking coffee either has no effect on them or might as well be a sedative as it makes them sleep off.
Caffeine works by blocking sleep-inducing chemicals in the brain and increasing adrenaline production. This temporarily makes the consumer feel more alert. After ingesting caffeine (most times in the form of coffee and sometimes in the form of cocoa, some soft drinks and certain drugs), it is absorbed from the gastrointestinal tract into the bloodstream and reaches its peak level in the blood within one hour and stays there for four to six hours. It diffuses throughout the entire body, passing all biological membranes, including the blood–brain barrier and the placental barrier. This is why pregnant women are cautioned to avoid it as it can induce foetal malformation by affecting the expression of genes that are vital in development.
Although caffeine should make people feel more alert, sometimes, it may not have the needed effect and this is dependent on certain factors. According to Dr. Irene Bassey, a medical practitioner,“caffeine is mostly found in coffee but sometimes it is added to other beverages and food products in small quantities to improve flavour and taste. Caffeine affects people differently. The difference varies based on their body size, their sex, and how sensitive they are to caffeine’s effects. There are genetic variations that can affect an individual’s level of sensitivity to caffeine.
“The fact is that though caffeine would keep you temporarily awake, when the effect wears off, you would experience a “coffee crash” and feel even sleepier. So, if you are planning on staying alert for long, you should actually stay away from caffeine. When you notice that drinking moderate cups of coffee doesn’t keep you alert, you shouldn’t overdose on it. Too much caffeine is not good for the body and can cause anxiety, headaches, nervousness and tremours. It can also lead to addiction. Four to seven cups of coffee a day is too much.”
Even in moderate portions, coffee may not be completely beneficial to the body. A report in the July-August 2002 issue of Psychosomatic Medicine pointed out that the more cups of coffee one takes throughout the day, the more experiences of fluctuations in energy and alertness, which can lead to chronic adrenal exhaustion. Besides temporary alertness, it has also been discovered to cause uneven heart rhythm, raise blood pressure and dehydrate the body owing to its diuretic properties. Researchers at the Department of Physiology and Biochemistry, University of Ilorin, Kwara State, in a study on the “Effect of caffeine on the risk of coronary heart disease — A re-evaluation” published in the Indian Journal of Clinical Biochemistry, add that caffeine predisposes consumers of caffeine-containing beverages to coronary heart disease.
The United States of America’s Food and Drug Agency also cautioned on the continued use of coffee that contains caffeine because of its addictive abilities. The agency stated that when people use caffeine every day, their bodies get used to it, and they don’t get the “good effects” of feeling more awake and able to concentrate unless they use more of it. This situation is called “tolerance.” If a person gets withdrawal symptoms when they suddenly stop using caffeine, then the person has a physical dependence (addiction) on caffeine.
Withdrawal symptoms include severe headaches, muscle aches, temporary feelings of depression, and irritability. Ironically, when people experience these symptoms, they often just take in more caffeine to make them go away and the cycle continues. Like every other form of substance addiction, it might require some form of intervention to break the cycle.
Whether coffee works for you or not, Dr. Bassey suggests that it is better to look for alternative means, which are healthy and have no side effects, to keep yourself alert. “Mild exercises or physical activity is one good way to get the heart pumping and keep one alert. You don’t want to exert yourself too much while exercising because that would also tire you out and make you sleep even better. A stroll, skipping or going up and down a flight of stairs can work. Also, doing things that stimulate the mind and brain can keep you alert. It could be a game or puzzle. It has to be something you enjoy so that boredom won’t also make you sleep off. Water and non-caffeinated teas are equally good beverages you can drink; these would not dehydrate you like coffee does.

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