CBS News Medical Correspondent Dr. Jennifer Ashton suggested a diet she says could do just that.
On "The Early Show" Tuesday, Ashton addressed a new Columbia University study.
She said it "looked at more than 2,000 New Yorkers and their self-reported diets. They found dietary patterns that were associated with lower risks -- people who had diets high in vitamin E, vitamin B 12, folate, omega-3 fatty acids and low in saturated fatty acids seemed to be protected against developing Alzheimer's."
Currently, Alzheimer's affects about 5.3 million Americans, according to the Alzheimer's Association.
On the broadcast, Ashton suggested people eat a combination of nuts, broccoli, romaine lettuce, and fish, instead of a diet filled with butter, steak, brie.
How does the diet help lower the risk of Alzheimer's?
Ashton said, "All together, a diet high in vitamin E, B12 and folate and low in saturated fats may protect the pathways to which Alzheimer's occurs. Vitamin E might prevent it by its strong antioxidant effect. A diet low in saturated fats causes clogged arteries and may be related to the development of dementia and inflammation in the body, which can affect the brain."
Ashton added, "The study does not promote one single source of food, but an optimal combination of nutrients."
Other than diet, certain lifestyle factors can also help lower your risks of Alzheimer's, Ashton said.
"The things that are good for your heart are also good for your brain and vice-versa, so you want to keep your weight down, minimize tobacco and alcohol use and exercise."
As for caring for patients with Alzheimer's or dementia, new guidelines are out from the American Academy of Neurology on driving and on-the-road safety. These guidelines serve to help doctors, caretakers and families determine when Alzheimer's and dementia patients should stop driving.
According to the study, as many as 76 percent of patients with mild dementia can pass an on-the road driving test, which means doctors and families need to help identify patients who should not be on the road, even if they can pass a test.
So how do you know when it's time to take the keys?
Ashton said warning signs may include if a person drives less, avoids certain driving situations -- such as when it's raining or dark outside, has accidents or traffic violations, and has aggressive or impulsive habits.
The guidelines also encourage caregivers to trust their instincts and listen to that gut feeling to help protect loved ones and others on the road.
Ashton said, "We know people with Alzheimer's can be at greater risk for motor vehicle accidents and it can be difficult to know when (to take the keys). The bottom line is it needs to be individualized."
Tests are available to help screen for unsafe drivers. Ashton said driving evaluations are available from certified professionals and occupational therapists who can help determine if a patient is still able to drive safely. These assessments may be available through rehabilitation programs and some state motor vehicle departments.
Another test is the Clinical Dementia Rating (CDR), which is done in an interview format and helps measure brain functions like memory, judgment and problem solving. The CDR is a tool for clinicians "to integrate information from caregivers and from direct examination of the patient to develop a comprehensive view of the dementia severity."
However, for many, driving means independence. So how do you prepare a family member or loved one for having the privilege taken away?
Ashton suggested these recommendations by the American Academy of Neurology:
She said, "When the diagnosis is given, have a conversation about the future and how you will face this challenge and what modes of alternative transportation are available. You should also monitor their driving, keep an eye on driving skills over time and patterns of behavior. You should look for support and ask for help and assistance -- their doctor can help facilitate between you and your family member -- ask them to write a letter or prescription that states 'no driving.'"