Tips for Avoiding Dementia

"Research has found a positive link between watching television for more than 3 hours a day and developing dementia."  Kahler Financial newsletter

Whenever I read of research like this, I wonder - which came first?  The carriage or the horse?  Is the dementia caused by the inactivity or by watching mindless television shows?  My thinking is:  probably both.  Inactivity is a significant factor in developing dementia.  Inactivity is often paired with a leisure activity, such as watching tv.  Social isolation is also associated with developing dementia, so in watching a lot of tv perhaps we create the 'perfect storm' of factors that contribute to dementia.  What better use can we make of our time?