8) Get a (social) life

Who needs friends? You do! Having multiple social networks helps lower dementia risk, a 15-year study of older people from Sweden's Karolinska Institute shows. A rich social life may protect against dementia by providing emotional and mental stimulation, says Laura Fratiglioni, M.D., director of the institute's Aging Research Center. Other studies yield similar conclusions: Subjects in a University of Michigan study did better on tests of short-term memory after just 10 minutes of conversation with another person.

9) Reduce your risks

Chronic health conditions like diabetes, obesity and hypertension are often associated with dementia. Diabetes, for example, roughly doubles the risk for Alzheimer's and other forms of dementia. Controlling these risk factors can slow the tide.

"We've estimated that in people with mild cognitive impairment — an intermediate state between normal cognitive aging and dementia — good control of diabetes can delay the onset of dementia by several years," says Fratiglioni. That means following doctor's orders regarding diet and exercise and taking prescribed medications on schedule.

10) Check vitamin deficiencies

Older adults don't always get all the nutrients they need from foods, because of declines in digestive acids or because their medications interfere with absorption. That vitamin deficit — particularly vitamin B12 — can also affect brain vitality, research from Rush University Medical Center shows. Older adults at risk of vitamin B12 deficiencies had smaller brains and scored lowest on tests measuring thinking, reasoning and memory, researchers found.

Beth Howard last wrote for AARP The Magazine about medical breakthroughs, in the September-October 2011 issue.

You May Also Like

• Dr. Oz's handbook for healthy living
  
• Plant veggies now for Spring and Summer eating
  
• Join AARP: Savings, resources and news for your well-being
• More health information you can use

Visit the AARP home page every day for great deals and for tips on keeping healthy and sharp