We consume hot water decoctions of Coffea arabica (coffee), Camellia sinensis (tea), Paullinia cupana (guarana), and Cola acuminata (used in Coca-Cola and similar beverages) mainly for their psychomotor stimulant properties due to presence of caffeine. Approximately 85 percent of the U.S. population consumes caffeine daily.

The FDA states that the regular consumption of 400 mg of caffeine (about four or five cups of coffee per day for the proverbial, non-pregnant, 70-kg adult) is quite safe. Habitual consumption of caffeine by children and adolescents is also considered safe because of similar caffeine clearance rates from the body.

However, typical of just about everything we consume, a little caffeine is good but too much can kill you. Approximately five grams of caffeine—about 25 cups of coffee drank quickly—is a lethal dose for a typical adult.

About 15 to 60 minutes after taking a few sips, we begin to feel the effects of caffeine; these may continue for around three to five hours (shorter if you are smoking a cigarette; longer if you are taking oral contraceptives). Caffeine is metabolized into two molecules that continue to stimulate the brain, paraxanthine and theobromine (which is also found in chocolate). Due to the competition with a specific liver enzyme, caffeine becomes more toxic when consumed while also taking some popular SSRI anti-depressants or medications to treat psoriasis.

Similar to the extracts from other plants, coffee is a blend of biologically active compounds that have health-promoting properties. Coffee produces many positive benefits for the cardiovascular system and brain.

Its pro-motility effects on the gastrointestinal system are well known, and often depended upon, due to its ability to........

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