Kuala Lampur, Aug. 19 -- We often associate dementia with old age. But protecting our brain should begin decades before memory problems appear and many of the choices that keep our heart healthy may also help our brain age better.

"Where did I leave my keys?"

"Why did I come into this room?"

"What was I about to say?"

Most of us have experienced moments like these. We laugh, blame stress, lack of sleep or an overloaded schedule, and continue with our day. But occasionally, a more unsettling thought follows: Could this be an early sign of dementia?

For most younger adults, occasional forgetfulness is unlikely to mean dementia. Being tired, distracted, stressed or trying to manage too many things at once can make anyone forgetful. Deme...