Three Simple Reasons why Tabletop RPG's are good for you

#1 We as a society (especially in America) are starved for real human contact. As Bowling Alone notes our social networks are fragmented and we spend far too much time in front of screens or by ourselves. This is not healthy for people.
RPG's are social and even open to people , able or disabled with strong or weak social skills and little or lots of money. They are an very egalitarian activity that gives us time with friends, fun and laughter. Thats something everybody needs and can benefit from

#2 They work the imagination in ways that more passive media (TV. Movie or Video Games) don't. Gamers may not be more imaginative than they general population but we use our imagination a lot more.

#3 They encourage reading and learning about all sorts of things. In the past this meant cracking books, reading Tolkien, Howard and Vance, obscure History books Osprey and more. Today it may mean Wikipedia. It doesn't really matter. This can spur a love of learning that can keep the brain healthier for a lifetime and make a better person to boot.