Learning a new language is good for your brain. Being able to speak and understand another tongue offers a form of mental stimulation, which keeps the brain active and sharp as we get older. In fact, researchers have found thatbeing multilingual may delay dementia diagnoses and slow down how fast the brain ages. Knowing more than one language — and practicing it often — is akin to constantly strength-training your brain. “If you are constantly using your brain for difficult, engaging and stimulating challenges, your brain will be healthier,” Bialystok said.