Many people believe that left-handed people are often geniuses. Is this true? About one in ten people are left-handed. Researchers looked at many studies about intelligence. They found almost no difference between left-handed and right-handed people.

So being left-handed does not make you a genius. But there is one interesting difference. Left-handed people are more likely than right-handed people to use the right side of the brain for language.

Many people believe that left-handers are more likely to be geniuses, partly because some famous artists and inventors were left-handed. About one in ten people are left-handed. In 2018, Greek researchers combined IQ data from about 20,000 people and found that the difference between left- and right-handers was so small that it could be ignored. One reason the myth survives is that famous left-handers attract attention, while ordinary ones do not.

However, left-handers' brains do differ in one way. Most people process language mainly in the left hemisphere, but a German study found that about 27% of strong left-handers used the right hemisphere, compared with only about 4% of strong right-handers.

Lists of famous left-handed artists and inventors have helped spread the belief that left-handers are unusually gifted. Large datasets tell a less romantic story. A 2020 meta-analysis put the share of left-handers at about 10.6%, although estimates run from about 9% to 18% depending on how handedness is measured. When a 2018 meta-analysis pooled IQ data from roughly 20,000 people, the gap between left- and right-handers was negligible. Right-handers scored very slightly higher, and even that edge vanished once the largest study was left out.

So why does the myth survive? Memorable examples stand out, ordinary left-handers rarely make headlines, and for some historical figures nobody reliably recorded which hand they used. Handedness does track real differences in brain organization. In a German study of healthy adults, about 27% of strong left-handers relied mainly on the right hemisphere for language, compared with about 4% of strong right-handers.

Left-handers may also have an edge in face-to-face sports such as boxing and tennis, where opponents are not used to them. Some researchers think this explains why left-handedness has lasted, but others dispute that idea. And the popular habit of sorting people into "left-brained" and "right-brained" types has no scientific backing.