In the first part of this series, we explored how the brain learns and remembers and how learning and memory, fundamental to our ability to negotiate our lives and maintain a cogent sense of self, slowly diminish as we age.
A certain amount of "benign forgetfulness" is a normal part of aging, most apparent as an inability to convert new short-term memories into long-term memories. So we forget where we put our car keys, but we'll never forget the color of our fifth-grade teacher's hair.
Sadly, our brains can also undergo abnormal aging. Dementia is a cognition disorder in which learning and memory become so impaired that they adversely affect normal daily life. Those affected can lose the ability to express themselves and understand others as well as the capacity to make routine decisions. Patients also experience depression, anxiety, apathy and delusions or hallucinations and can lose all insight into what is happening to them (known as anosognosia).
The most common cause of dementia is Alzheimer's disease, which currently affects more than 5 million people in the United States. The precise cause is still unclear, but evidence points to the accumulation of abnormal proteins in and around the nerve cells of the brain, disrupting synapses and nerve conduction. Genetics play an important role in Alzheimer's disease, but increasingly we're realizing that lifestyle choices can make a dramatic difference in reducing the risk, even for people genetically predisposed to dementia.
Here are some ways to lower your chances of developing dementia and Alzheimer's disease and stay cognitively fit:
Avoid head trauma
We're now aware of the dangers of contact sports, especially football, but head trauma later in life can be even more devastating. One study found that over a follow-up period of three years after a concussion the risk of Alzheimer's disease increases more than 40 percent. Work on your balance with yoga or practice balancing on one foot while you're brushing your teeth. Wear a helmet whenever you're engaging in high-impact activities such as skiing.
Don't smoke and/or drink to excess
And don't overuse psychoactive medications. Recent research has shown that even modest use of benzodiazepines (drugs like Xanax and Valium) for a period of three months can substantially increase your risk of Alzheimer's disease.
There is lots of evidence that a Mediterranean-style diet (whole grains, fish, fruits and vegetables, nuts and a daily glass of wine) can substantially lower your risk of dementia and cognitive decline. A newer diet, the MIND diet, combines elements of the Mediterranean diet with the DASH diet. The latter, a diet high in fruits and vegetables and low in salt, has been shown to lower the risk of high blood pressure. Even modest adherence to the MIND diet has been found to reduce the risk of dementia by more than a third in elderly patients when followed for more than four years.
There is no convincing data that vitamin supplements can make an important difference. Studies are limited, but no study has yet found a magic bullet. Among the disappointments are ginkgo biloba, omega-3 fatty acids, antioxidant concoctions and multivitamins. It's better to get your nutrition from real foods.
Keep physically fit -- now
Fitness at a young age correlates with better cognitive function as we age and a lower risk of dementia.
Use your brain
No, it's not a muscle, but it responds like one to use and underuse. People of any age who keep intellectually stimulated have a remarkably lower risk of cognitive decline. Things you can do:
- Learn a language.
- Challenge yourself, even to something simple like taking a new route to work or learning a new skill or sport.
- Be creative and stay engaged. Involvement in the arts and music is highly protective, so paint, write that novel or, best of all, listen to new and different types of music or study a musical instrument. Nothing gives the brain a workout like music: You can see almost the entire brain light up with activity on a functional MRI scan when you listen to music.
- Don't count on "brain-fitness apps" to keep you smart. The evidence so far shows that these apps do have an effect on cognition, but the effect is only temporary and is not generalizable. In other words, using "brain apps" makes you better at using the apps, but not much else.
No matter your family history or even your own personal history, you can do lots of simple things that are good for your brain and keep you firing on all intellectual cylinders for many years to come. And, as an added bonus, many of these lifestyle interventions are the same ones we recommend for heart health and reducing cancer risk.
Readers -- Are you worried about dementia or Alzheimer's? Do you do any of the activities mentioned above to keep your brain "active"? Have you ever tried "brain apps"? Leave a comment below and let us know.
Malcolm Thaler, M.D. is a physician at One Medical Group. He enjoys being on the front lines of patient care, managing diagnostic and therapeutic challenges with a compassionate, integrative approach that stresses close doctor-patient collaboration. He is the author and chief editor of several best-selling medical textbooks and online resources, and has extensive expertise in managing a wide range of issues, including the prevention and treatment of cardiovascular disease, diabetes and sports injuries.