Yahoo! reports on a new study that shows the mental health benefits of speaking two languages.

Bialystok studied 450 Alzheimer’s patients, all of whom showed the same degree of impairment at the time of diagnosis. Half are bilingual — they’ve spoken two languages regularly for most of their lives. The rest are monolingual.

The bilingual patients had Alzheimer’s symptoms and were diagnosed between four and five years later than the patients who spoke only one language.