Over half of the world's population speaks more than one language. However, as little as 1 percent of the planet’s people can be considered a polyglot, defined as someone who can speak five or more languages. Moreover, there are some individuals known as hyperpolyglots, linguistic maestros that master an abundance of language (although there’s no strict definition of how many languages are required before you are welcomed into this elite group).

History is full of this fascinating species. There’s Giuseppe Caspar Mezzofanti (1774-1849), an Italian Cardinal who purportedly spoke more than 38 languages fluently, as well as Sir John Bowring, Governor of Hong Kong from 1854 to 1859, who claimed to know 200 languages and could speak 100.

These claims, however, have never been robustly verified (more on that later) and history has a tendency to regurgitate tall tales not wholly based on truth. 

Theoretically, there is no definitive limit to the number of languages a human brain can comprehend. It’s also an impossibly tricky thing to quantify; is it harder to grasp the basics of hundreds of languages or deeply understand a handful?

In 2018, the New Yorker took a deep dive into the world of hyperpolyglots and reported that many “winced at the question” when asked how many languages they speak. Simply put, it’s not easy – or even useful – to count the number of conquered languages. 

“No one masters all the nuances of a language. It’s a false standard, and one that gets raised, ironically, mostly by monoglots – Americans in particular,” Richard Simcott, a British hyperpolyglot who organizes the annual Polyglot Conference, said in an interview with the magazine. 

There is also the problem of substantiating the claims of hyperpolyglots. If someone claimed they spoke 10 of the world’s rarest languages, would they have to gather native speakers from every corner of the globe to prove it? 

Case in point, there is the infamous tale of Ziad Fazah, a semi-celebrity of Lebanese heritage who spent large parts of his life in Africa and South America. Up until 1998, he held the Guinness World Record for the most languages spoken after claiming he had learned 59 world languages, from Arabic and Spanish to Swahili and Tajik.

However, many felt that parts of his story were fishy, to say the least. In 1997, he appeared on a Chilean TV show called Viva El Lunes in which he was grilled by audience members from around the world, including Egypt, Finland, Iran, Russia, China, Greece, and India.

It became apparent that Fazah had overstated his competence in many of these languages and failed to answer some of the basic questions. 

He later said the TV show was an essential set-up by sensation-seeking producers who didn’t tell him he’d be tested live on the show. He told La Cuarta newspaper in 2020: “I hadn't practiced for a long time. The truth is, it was a huge embarrassment.”

Whether you can speak two or 200 languages, it’s evident that the brain always holds a special place for our native tongue. A study published earlier this year by scientists at MIT analyzed the brains of polyglots as they mused over their many languages.

The same brain regions “lit up” when they listened to any of the languages they spoke and the activity was stronger in those in which the speaker is more proficient – except for their native language. Whenever they listened to their primary language, activity in the brain network was significantly lower. 

“Something makes it a little bit easier to process – maybe it’s that you’ve spent more time using that language – and you get a dip in activity for the native language compared to other languages that you speak proficiently,” Evelina Fedorenko, an associate professor of neuroscience at MIT and the senior author of the study, said in a statement.

Becoming a true hyperpolyglot is said to be a Herculean feat that requires years of dedication, but you don’t need to achieve any superlative challenges to gain some clear benefit from learning multiple languages.

A study from 2020 suggested that multilingualism may delay the onset of Alzheimer’s disease. The learning of another language does not prevent or reverse dementia, as such, but it does help to strengthen and reorganize the brain’s circuits. This is particularly useful when the brain is put under strain in old age as it helps distribute activity throughout more brain circuits.

Granted, learning 10 languages won’t increase this effect by 10-fold, but dabbling in a bunch of different dialects is unlikely to harm you.