By Dr. Simon Evans and Dr. Paul Burghardt

For some time now, we’ve been promoting the role of a healthy lifestyle in maintaining brain fitness. Another new study lends more support, but before we get into that we thought we’d focus on some common-sense topics as to why this is true.

One simple concept to understand that doesn’t require a PhD is the fact that any organ in your body, including your brain, needs a healthy blood supply to access nutrients and oxygen. This is one reason why heart disease and mental health problems, including dementia are so often related. If you tied a tourniquet around your leg to cut-off the blood supply, you shouldn’t be surprised when your foot stops working to well.

The same is true for your brain. If you continue to do things that are bad for your cardiovascular system, like sit around all day and eat chips, your vascular system will eventually have a problem, and this is not good news for your brain. In fact, your brain uses about 20% of the oxygen that you breathe and the calories that you eat. Your blood supply is responsible to get that stuff to the right place in order to keep your brain in good working operation.

The benefits of life-long learning and continually challenging your mind to keep it sharp are well established. But if you don’t couple that effort with doing what’s necessary to maintain a healthy neurovascular system, you cannot fully realize the benefit. You may have read a lot about neurogenesis and synaptogenesis, which is the constant rewiring of your brain that occurs when you stay mentally active and helps to keep your mind agile. However, this process can only work well if the blood vessels near all this rewiring are healthy enough to do their job. Otherwise, where is the energy, nutrients and oxygen necessary for the remodeling job going to come from?

Think of neurogenesis as a new housing subdivision going into an existing community and the roads as the blood supply to service the houses. If you were the builder constructing this new development you wouldn’t get very far if you didn’t first attend to the new roads. Not only are the roads needed for the new owners to get in and out of their homes; but they are needed for delivering all the lumber and concrete, enabling the different crews to come in and construct the new houses, and take all the trash away. Similarly, new brain cells or new brain cell connections need healthy roads (neurovascular system) to work right.

Related to this, a recent large study, just unveiled this month (April 2008) by Dr. Thomas Montine from the University of Washington, reports that 33% of the risk of dementia stems from disease of small blood-vessels in the brain. In this 12-year study, 3,400 men and women over age 65 volunteered for periodic cognitive testing and a brain autopsy upon their death. In the 221 autopsies performed, researchers discovered that small blood vessel disease accounted for about 1/3 of the risk for dementia. Importantly, this type of small blood vessel disease may go unnoticed for some time. We’re not talking about big events like a stroke or blood clot blocking a large vessel. However over time these small problems can add up, and result in cognitive impairment.

Admittedly, this study comes from the Pacific Northwest, the origin of grunge-rock and Starbucks coffee. We can’t be sure that all these people aren’t suffering from some kind of post-angst cognitive disorder, or a latent flannel shirt allergy! We also can’t rule out suffering from some sort of post-tramautic stress after invading the world with high-priced coffee, equivalent to about $18.00 per gallon; slightly more than we’re currently paying for gas. In fact, one of us (Evans) was raised in Seattle and may be showing some early symptomology.

However, with these potential confounds aside (unless Austin Powers was right, and during the time that Dr. Evil was cryogenically preserved his faithful cronies invested heavily in Starbucks), this study is an incredibly important step that illustrates the diversity of factors that can lead to dementia. Even more importantly, it suggests that you can substantially decrease your odds of developing dementia by attending to life-style factors that can protect against vascular disease.

The beauty is that we have a good idea of how to do this since blood vessels serve to supply active areas of the body with nutrients! So if your brain is active (which requires energy), and you’re maintaining your overall vascular health by eating right and exercising, odds are that you will be greatly reducing your risk of developing dementia from small vessel disease. Now it should be noted that research is ongoing on this subject, but common sense would suggest that this will hold true.

Taken together this highlights some very important reasons as to why exercise and nutrition play such a crucial role in brain fitness. Attending to both of these lifestyle factors is necessary to maintain a healthy blood supply and the creation of new blood vessels, in order to feed new brain circuits established by learning and mental activity. If you neglect this aspect of brain fitness, you may literally limit your ability to benefit from neurogenesis and synaptogenesis induced by many of the ‘brain-training’ programs designed to keep your mind young.