- Scientists pinpoint why coffee can ward off Alzheimer’s
- The key compounds appear to be phenylindanes
- Darker roasts, even espresso, offer the greatest benefit
Scientists have been saying for a while that drinking coffee may reduce the chances of acquiring Alzheimer’s disease (AD), Parkinson’s (PD), and dementia. A new study has taken a look at the chemistry behind the correlation between Joe and lower incidences of AD. Co-author Donald Weaver tells Medical News Today that “we wanted to investigate why that is — which compounds are involved and how they may impact age-related cognitive decline.” Their identification of phenylindanes compounds as the source of java’s beneficial effect leads to a couple of surprises. First off, decaf is just as effective as caffeinated coffee at avoiding the disease. Second, what really matters is how dark the coffee’s roast is.
The experiments started much like our days
For analysis, researchers’ stock solutions began with Starbucks 100% Arabica instant coffee in light roast, dark roast, and decaffeinated dark roast varieties.
While the caffeine in coffee is known to produce a short-term increase in alertness, its long-term effect on the brain is less understood, especially since the amount of caffeine in any given cup is dependent on a host of variables, so controlled testing has been tricky. And there are a number of chemicals in java.
Weaver’s team was concerned with “identifying naturally occurring small molecules which can inhibit the aggregation of amyloidogenic proteins” that build up and are believed to be a factor in Alzheimer’s.
Ultimately, they found that the absence or presence of caffeine made no difference to the aggregation of the toxic proteins. Also ruled out as being of much use were chlorogenic acids — compounds that account for as much as 15% of unroasted beans — as well as quinic acid, caffeic acid, and quercetin.
It’s really about the phenylindanes
When coffee beans are roasted, compounds called phenylindanes are generated. The darker the roast, the more phenylindanes are produced. According to the paper, it turns out that it’s these compounds that inhibit the aggregation of the Alzheimer’s inducing tau and beta-amyloid proteins. Weaver admits, “So phenylindanes are a dual inhibitor. Very interesting, we were not expecting that.”
What all this means is that if developing a neurodegenerative disease, especially Alzheimer’s, is a concern, try switching to as dark a roast of coffee, or even espresso, as you find palatable. Caffeinated or not makes no difference in this regard, though the other effects of caffeine are, of course, a whole other issue.
Also, note that there’s no indication that drinking coffee does anything to cure Alzheimer’s. It simply seems to help avoid acquiring it.