When people think of caffeine, they often think of the coffee beverage or coffee beans, which today are indeed the biggest source of the stimulating chemical in the world. But several popular plants worldwide – around 60 species of them – contain caffeine that have been made into delicious food and drinks from antiquity.
Many of the plants below not only contain caffeine but also are good sources of theophylline and theobromine, two other mild stimulants that scientists believe have some beneficial effects. (Theo means “god” in Latin.)
Is it true caffeine makes you smarter? Sort of, it seems, at least indirectly. Researchers have studied this question a lot, and two groups of researchers did meta-studies (studies of studies) to determine just exactly what, if any, the conclusions of the scientific literature are.
If the title sounds like we’re hedging our bets, we are.
Whether caffeine makes you smarter is one question. Whether it makes you feel good is another. Test subjects in studies report they’re in a better mood after taking caffeine, they’re more alert and less fatigued.