THE SCIENCE OF OUR HEART-BRAIN CONNECTION

The key to staying sharp and keeping your mind in tip-top shape as you age? Protect the health of your ticker right now.

- TONI HOPE

IF IT SEEMS THAT THERE ARE MORE PEOPLE WITH DEMENTIA THAN THERE USED TO BE, IT'S NOT YOUR IMAGINATION.

Right now 6.5 million Americans ages 65 and older are living with it, and by 2050 that number is projected to have risen to 12.7 million, according to the Alzheimer's Association. A big reason: the state of our heart health.

The brain requires fuel to function, and it gets its fill when the heart pumps lots of oxygen and glucose-containing blood upward, says Constantino ladecola, M.D., director of the Feil Family Brain and Mind Research Institute at Weill Cornell Medicine. But the brain doesn't have any reserves of this crucial resource. Consider your heart and blood vessels as supply lines to a remote city with no grain silo, Dr. ladecola says. "If the tracks don't work, the city doesn't eat and the people starve."

The lifestyle factors that keep your heart in good shape are the same ones that may dramatically lower your risk of brain-health issues as you age. Though there is no cure for dementia, "taking steps to prevent heart disease, which we do know how to do, can have a big impact on cognitive disorders," explains Rebecca Gottesman, M.D., Ph.D., senior investigator and stroke branch chief at the National Institute of Neurological Disorders and Stroke.

In fact, your cardiovascular fitness may be the most important factor in keeping your mind sharp for the long haul. The evidence overwhelmingly supports this notion: In a study from Finland, people with the best cardiovascular scores at midlife cut their risk of developing dementia later in life by up to 40% compared with those who had the worst scores. In another study, Swedish researchers found that the more quickly people developed cardiovascular risk factors, the more likely they were to experience Alzheimer's and dementia.