A new study says cardio exercise can reduce a person's risk of dementia and Alzheimer's.

The study, published in the British Journal of Sports Medicine, found that people who are considered middle to old age can reduce their risk of developing the disease by regularly exercising.

Researchers looked at data from more than 61,000 people over a 15-year period and found that "good cardio-respiratory heath" can help delay the start of dementia by 1 and 1/2%

For people who are genetically predisposed to Alzheimer's, exercise can help reduce their risk by one-third.

The American Heart Association has found that a lack of exercise can decrease a person's health by 3-6% each decade, starting in their 20s and 30s. The decrease grows to more than 20% in your 70s and beyond.

Dr. Marc Otten, a neurosurgeon at Orthopedic & Neurosurgery Specialists, says it's not too late to begin eating healthy foods or start working out and receive benefits.

"There's a lot that can be done years before those problems creep up. The good news is that taking care of our bodies is one of the early steps in taking care of our brains," he says.