Many baseball players chew gum during games. Some students say gum helps them study. Is it true? Many scientists have tested this. Chewing gum may help people feel more awake and keep their attention during long, boring work.

But the effect is small. In one study, it lasted only about 15 to 20 minutes. Gum does not make you smarter, and it may not help your memory.

Baseball players often chew gum, and some students believe it helps them concentrate. Researchers have tested this idea many times, but the results are mixed. In 2002, a British study reported that people who chewed gum remembered words better.

However, later studies often failed to find the same effect on memory. In a German study, gum helped people keep their attention for a long time, but it made quick reactions worse. An American study found that chewing gum for about five minutes before a test improved some scores, but the benefit disappeared after 15 to 20 minutes. Chewing throughout the test did not help. Gum may wake us up a little, but it is not a magic study tool.

The image of baseball players chewing gum has encouraged a popular belief that chewing sharpens the mind, and researchers have tested it repeatedly, with confusingly mixed results. A 2002 British study reported that gum chewers performed better on some memory tests, such as recalling words, but later attempts frequently failed to replicate this.

A German experiment comparing no chewing, mock chewing, flavorless gum and mint gum found no memory benefit; chewing improved sustained attention but actually impaired quick reactions and task switching. An American study offered a possible explanation for the inconsistency. Chewing for about five minutes before testing improved performance on some tasks, but the benefit faded within 15 to 20 minutes, and chewing throughout the test brought no gain.

The researchers suggested that chewing produces a brief rise in arousal, while continuous chewing may compete for attention. A 2015 paper reporting four studies found higher alertness among gum chewers and a smaller drop in alertness over a working day. Even these effects are small, and differences in flavor, expectations and study design make comparisons difficult. Gum may help as a wake-up aid, but it will not make anyone cleverer.