Wednesday, April 29, 2015

Mediterranean Diet Makes Brains Bigger?

The news is on professional sites and in the news media. Astounding evidence from a single study of a group in an upper New York City area appeared to indicate that adhering to the Mediterranean diet resulted in "bigger brains" and, apparently, a lower incidence of Alzheimer's. The study intrigued me especially since the media were almost shouting about "bigger brains" from the diet.

Bigger brains in older Manhattanites? Could that only be a good thing or was there something else here? Remember, if you have a bigger brain, doesn't that indicate something not necessarily good? Don't we try to avoid traumatic brain swelling (i.e. bigger brains)? There's only so much room in our packed craniums, so how could we manage bigger brains? Turns out the "bigger brains" terminology was all wrong.

What the researchers really found was that, in a non-demented sample (that's important here) there was less shrinkage or atrophy in this sample when measured with highly sophisticated imaging equipment. Atrophy is something that happens with normal aging, it seems, and doesn't necessarily mean you're headed for dementia, although that's what it sounds like, doesn't it?

Brain cell death begins even before birth and throughout our lives these cells sluff off like our skin cells. They are replaced and continue to grow. In fact there's a storehouse of stem cells just waiting to be called up to action in one of the several brain holes (okay, they're called ventricles) however, and exercise and learning appear to be two of the most exquisite means to get nerve cells to sprout even more.  Sounds really promising, so get out your treadmill or bike and go to it to keep those little cells on that trajectory to growth.

The most interesting thing about the recent study, however, wasn't the diet aspect. As one very well-known expert on Alzheimer's and dementia, Dr. David Knopman of the Mayo Clinic stated, the fact that those in the study were on this diet may not necessarily be the key to defeating Alzheimer's.

There are many more factors that need to be considered. For me, one of the factors missing in the study was that these were all non-demented individuals. I think that a better design would have compared those on the diet and those not on the diet and see which group may have had less atrophy and, more importantly, less cognitive impairment. Also, when did each individual start the diet?

The particular area of Manhattan where the study participants lived is heavily populated by one or two distinctive ethnic groups and that further limits what we can say about the results. Lifestyle, cultural differences, religious beliefs, socialization and other factors also need to be entered into our multiple regression formula here. I do assume that was the mathematical approach they took here. A diet heavy in fish and light on beef may be good for health, but it's not necessarily the determining factor in brain atrophy, neurogenesis or dementia. Stress remains paramount in everything. Did anyone measure the stress levels of this group or how community identity affected stress?

We've seen rather shocking brain imaging studies of a young girl who had a brain that was so deficient in cells that it was more like a ring of cells rather than a plump ball.  It could remind you of the neural ring found in the "brain" of earthworms that we had to dissect out in our college biology class. The study I saw indicated that the girl was functioning normally even though she had a major deficiency in brain mass. So, is mass the key here or can we function on less massive brains? Quite an interesting question to me.

Word to the wise: Question the studies. I know it's challenging for media writers to make some of them sufficiently news worthy, but let's not get so carried away that it's absurd when the actual study is reviewed.

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