Multilingual people may have brains up to 13 years younger

"People who spoke two languages had brains about six... three about seven... and four roughly 13 years younger."

I am fluent in at least 10 programming languages. Do those count ? Probably, if this study revealing a hidden correlation such as socioeconomic level. But they did reference that possibility.

"The researchers adjusted their analysis for factors including age, sex and education... lifestyle and social engagement, could also contribute to the differences they observed."