We all want to dodge the Alzheimer's bullet. And lucky us, Mother Nature has counterbalanced the power of our hard-wired genes by allowing multiple lifestyle choices to greatly influence our aging.
Your destiny is not fated; you do have some control. Yes, genes are powerful forces but they "are not even the dominant factor" for the vast majority of people, says Paul Thompson, professor of neurology at the University of California-Los Angeles School of Medicine.
Here are some factors you can take action on to help your brain stay healthy over the long term:
Recent research from the University of Illinois suggests that regular aerobic activity -- like running, walking or bicycling, which require oxygen to produce energy -- may do a better job of protecting brain function than non-aerobic activity, which does not recruit oxygen and uses short bursts of motion (golf, tennis, lifting weights).
Reaping the cognitive benefits of pumping oxygen- and sugar-rich blood to the brain won't require high intensity exercise, says William Thies, chief medical and scientific officer of the Alzheimer's Association. The Alzheimer's Association advises picking activities you like and doing them regularly for at least 30 minutes a day.
The heavier a person is, the more likely he or she may be to develop Alzheimer's. Thompson published research in August that found that the brains of older individuals who were obese (with a body mass index over 30) had approximately 8 percent less brain volume than subjects of normal weight (BMI between 18.5 and 25).
When brain-volume loss reaches about 10 percent, Thompson says, symptoms like memory trouble or confusion appear. Earlier studies have suggested that people who are obese in mid-life have a threefold increased risk of developing Alzheimer's, and those who are overweight (considered a BMI between 25 and 30) have a twofold increased risk. This is due, at least in part, to the fact that with added pounds, fat gets deposited in the brain and narrows blood vessels that deliver fuel, Thompson theorizes. Over the long term, brain cells die and vital connections and volume are lost.
No, it's not just about doing sudoku -- though puzzles do fall into the category. The brain's ability to reorganize neural pathways with new information or experiences means it's regularly changing; we can even generate new brain cells. But you need to work it.
The general guideline, says Neil Buckholtz, chief of the dementias of aging branch at the National Institute on Aging in Bethesda, Md., is regularly engaging in "some kind of new learning that challenges you." No one knows exactly what works, though population research has shown that having more years of formal education seems to be protective. Folks with lots of schooling can still get Alzheimer's, but the disease may appear later. From that, some extrapolate that lifelong curiosity and learning may have benefits.
Research has found that people with larger social networks, while they had similar amounts of the plaques and tangles of Alzheimer's disease as did more isolated people, were less affected cognitively. And separate research suggests that psychological distress over the long term significantly raises a person's risk of developing Alzheimer's.
Thies predicts that science will eventually reveal that "this kind of interaction stimulates the brain to make new connections" that perhaps help compensate for decline. To get a threefer, try learning the intricate steps of the tango in a dance class with your friends.
"What we have pretty good evidence for is that a diet higher in vegetables and lower in fat is [protective]," explains Thies. While the evidence doesn't offer any recipes for success, the general recommendation is to get plenty of veggies and fruits with dark skins, like spinach, beets, bell peppers, eggplants, prunes and blackberries, according to the Alzheimer's Association.
Some evidence suggests green, leafy cruciferous vegetables, in particular, are helpful. Eating fish high in omega-3 fatty acids may be beneficial. So may some nuts, such as almonds, walnuts and pecans, that have high levels of vitamin E, an antioxidant. Research published in February in the Archives of Neurology suggested that a Mediterranean diet appears to be protective against Alzheimer's.
Some animal research has shown that curcumin, which is in the curry spice turmeric, suppresses the buildup of beta-amyloid, a main component in the harmful plaques in the Alzheimer's-afflicted brain.
>Chronic disease control
Buckholtz notes that "high blood pressure in old age is a very strong risk factor for developing Alzheimer's later on." And a study published in August 2009 in the journal Dementia and Geriatric Cognitive Disorders found that people in their 40s who had mildly elevated cholesterol were at greater risk of developing Alzheimer's later in life.
A sizable body of evidence suggests that type 2 diabetes and heart disease affect the brain and perhaps the development or severity of Alzheimer's.