Knowing more than one language has benefits beyond the ability to order cervezas and croque-monsieurs with a convincingly suave accent. New research has found that bilingual people have added protection against Alzheimer's disease. Here, a brief guide to the findings:

What exactly have researchers found?
In a recent study at Toronto's York University, psychologist Ellen Bialystock found that bilingual Alzheimer's patients were diagnosed, on average, 4.3 years later and reported the first onset of symptoms 5.1 years later than their monolingual counterparts. Additionally, even with advanced brain deterioration, bilingual patients performed as well as monolingual patients with less brain deterioration. "They can cope with the disease for longer," Bialystock said.

Why does being bilingual help?
Researchers think the findings are related to a highly important brain network called the executive control system, which forms the basis of complex thinking. It's believed that speaking more than one language helps develop this part of the brain, and with it, the ability to cope with diseases like Alzheimer's. "It is rather like a reserve [gas] tank in a car," says Bialystock. "When you run out of fuel, you can keep going for longer because there is a bit more in the safety tank."

Do you have to be fluently bilingual to benefit?
According to the study, those that simply studied a language in school and use it to order drinks on holiday will experience some positive effects, though the benefits are greatest for those who used their language every day.

Do these findings conflict with previous notions of how the brain works?
Yes. Some believe that bilingualism confuses the brain, and that bilingual individuals, especially children, have difficulty using either language. That's not true, says Judith Kroll, the psychologist behind a similar Penn State University study. "The bottom line is that bilingualism is good for you."

Sources: Guardian, Fox News, National Geographic