Outgoing people are 50% less likely to develop dementia, according to a recent study of more than 500 men and women age 78 and older from the Karolinska Institutet in Sweden. Participants also described themselves as not easily stressed. Researchers speculate that their more resilient brains may be due to lower levels of cortisol -- studies show that oversecretion of this "stress hormone" can inhibit brain cells' communication. Science-backed ways to cut cortisol levels: Meditate, sip black tea, or take a nap.

Exercise your mind with these memory and brain games.

More links:

Follow MSN.ca Lifestyle (@MSNcaLS) on Twitter!