Mediterranean Diet, Physical Activity, and Risk for Alzheimer’s

Studies reported in this week’s  Journal of the American Medical Association (August 12, 2009) support the relation of physical activity and the Mediterranean diet to reduced risk for Alzheimer’s disease. The first study, by Scarmeas and his colleagues, showed that persons who report following the Mediterranean diet and who are more physically active were less likely to develop Alzheimer’s disease over several years. The average age of the participants was 77 years, so this group (called the Northern Manhattan cohort) would have been at higher risk than younger individuals.

The second study, by Feart and her colleagues, looked at adherence to the Mediterranean diet and risk for having problems on certain mental ability tests. Here again, the study suggests that following the Mediterranean diet was associated with a reduced risk of developing certain kinds of cognitive problems.

The study was discussed by Dr. Nancy Snyderman on the Today Show. You can find a link to a page that will let you see the segment from the show here.  (Look for a link to “Study: Mediterranean diet cuts Alzheimer’s risk.” You also have to watch a commercial; that’s NBC, not me).  I think that she may overstate the case based on the research; there’s a very nice editorial in this same issue of the Journal by well-known neurologist David Knopman. He points out a number of possible reasons for these findings that might affect the conclusion that the Mediterranean diet and exercise reduce the risk of Alzheimer’s. He suggests we should “nibble and savor” the results of these studies, not “swallow them whole.”

It’s still premature to be sure that following the Mediterranean diet or being physically activity will prevent Alzheimer’s disease. Given what we know about the relation of cardiovascular health and risk for Alzheimer’s, and what we know about diet and exercise and cardiovascular health, though, I think it’s a good idea to pay close attention to your diet and to exercise safely.


Latest

Mindfulness meditation as practiced over a long period by experts makes clear changes in someone’s brain function. But what about those of us who don’t have a few years to sit in a monastery in the Himalayas? A new study shows that even brief meditation practice can improve attention.

Researchers at Wake Forest University studied whether just four days of training (at just 20 minutes a day) could make a difference in participants’ mood, energy, and cognition. Undergraduate students (average age 22 years) either participated in the meditation sessions or spent a similar amount of time sitting quietly and listening to an audio book.

Participants in the meditation condition showed decreases in anxiety and improvements in several mental processing tasks compared to those in the audio book group. The meditators’ performance on one aspect of a working memory task (how many answers they got correct in a row) suggested that they may have improved their attention.

This is a small and very preliminary study that extends others’ work on meditation and the brain.It shows that even brief meditation practice can make a difference. you don’t have to be a Buddhist monk to learn to still your mind and pay better attention. Paying attention may be one of the most important things you can do to improve your brain’s functioning.

Reference:

Zeidan F et al.(in press) Mindfulness meditation improves cognition: Evidence of brief mental training. Consciousness and Cognition, doi:10.1016/j.concog.2010.03.014

I saw an interesting blog post yesterday evening on the site of the Huffington Post about the potential benefits of meditation – or at least about what one woman thinks might be the benefits. Priscilla Warner writes about the contrast between Tibetan monks’ apparent calm, evident even on brain scans, and her own anxiety disorder. Ms. Warner says that she suffers from panic disorder, a severe form of anxiety in which a person can have multiple anxiety attacks every day, even in the middle of the night. Her post is titled “I Want the Brain of a Monk” Although most people don’t suffer from anxiety this severe, many people have symptoms of anxiety. And research has consistently shown that higher levels of anxiety are related to more memory problems.

What’s the relation to brain fitness? In my brain fitness class, I often mention the usefulness of meditation in helping reduce stress and anxiety, both of which have negative effects on memory. You don’t have to go to Tibet to get the benefits of meditation. If you simply take 10 minutes several times a day to break in to the ongoing rush of getting things done, you’ve made a start. Use those 10 minutes to sit quietly, relax your muscles, and breathe deeply.

If you do that every day for two weeks, I think you’ll notice that you feel calmer and better able to focus. And if you’re better able to focus, you will be better able to pay attention and remember things.

Although many people are excited about the potential for using computers to train their brains, we shouldn’t forget that other techniques have been used to the train the brain for many centuries. I’m thinking about the large number of techniques for meditation. While free computer software still requires an investment in a computer, meditation only asks you to sit or lie quietly and focus your mind.

A recently-published study shows parts of the brain in long-term meditators are larger than the same parts of the brain in people who don’t meditate. The article by Eileen Luders and her colleagues appeared in a recent issue of the journal Neuroimage (Vol. 45, No. 3, pp. 672-678, April 15, 2009). The study showed that portions of the orbitofrontal cortex and the hippocampus were larger in persons who had been regular meditators for 5 or more years. The study is interesting because the parts of the brain that were larger are often thought to be important in helping people keep themselves emotionally balanced.

A number of strategies are likely to be helpful for meditators. There has been a great deal of interest over the last several years in mindfulness meditation. Researchers have studied how it can be used in reducing anxiety and depression. Mindfulness is based on Buddhist meditation (for a brief article, click here) but you don’t have to be a Buddhist to practice meditation. In fact, one of the most important persons who has promoted mindfulness is Jon Kabat-Zinn, a researcher at the University of Massachusetts. You can see a video presentation by him on YouTube by clicking here.