28 November 2014

Chocolate for Health

A cacao tree with ripe pods of cacao.
(www.loizadark.com/index.html)
“You’re kidding,” I said, the first time I saw hand-sized, football-shaped pods growing from the trunk and branches of a small tree. “That’s cacao?”

We sliced open a pod to examine the beans, which could have been processed to produce cocoa or chocolate if cacao growing in Puerto Rico hadn’t ended long before my “discovery” in that abandoned field in the 1960s. (Not to worry, chocolate lovers; cacao growing has returned along with artisan chocolate production.)  

 

A cacao pod cut open to expose
the mucilage-covered beans.
(www.loizadark.com/index.html)
Welcome back. I can’t delay this topic any longer; I am engulfed in chocolate and I don’t mean Halloween leftovers. Research reports on the potential health benefits of chocolate or at least of flavonoids in cacao (Theobroma cacao) keep coming, especially for cardiovascular health.

As I wrote earlier (Tea Time), tea, coffee, cacao and many fruits and vegetables are loaded with polyphenols, particularly flavonoids, which have antioxidant and other potentially useful properties. Flavonoids probably didn’t make it to my Halloween candy, but let’s start with the research findings.

Cognitive Function

Two years ago, an investigation led by researchers from Italy’s University of L'Aquila found that mild cognitive impairment in individuals, ages 64 to 82, improved with consumption of cocoa flavanols, a subclass of flavonoids.

Once daily, 90 test participants downed a drink that contained either low, medium or high levels of cocoa flavanols. After eight weeks, tests of memory and verbal fluency showed participant scores that aligned with the low to high flavanol levels. Blood pressure and insulin resistance also decreased among those who had consumed higher levels.

Hold that thought, because last month, a published report suggested that cocoa flavanols may go beyond improving to actually reversing age-related memory decline.

The recent study, led by investigators from Columbia University, had 37 healthy participants, ages 50 to 69, on a high or low flavanol diet for 3 months. Memory tests were given at the beginning and end of the study, and the participants were also examined with functional magnetic resonance imaging. The fMRI focused on the dentate gyrus of the brain’s hippocampus, which previous research has shown to be associated with memory decline typical of aging.

The study’s high-flavanol diet participants exhibited a marked improvement in cognitive and dentate gyrus function, establishing that dentate gyrus dysfunction is a driver of age-related cognitive decline and pointing to flavanols as a non-pharmacological means for its amelioration.

Possible Explanation of Health Benefits

At this year’s national conference of the American Chemical Society, a team of researchers from Louisiana State University reported laboratory simulation findings that may help explain the reason dark chocolate has health benefits.

The researchers tested three cocoa powders, employing a series of modified test tubes to simulate the digestive track. They then subjected the non-digestible residuals, which contained poorly digested polyphenols, such as flavanol, and small amounts of dietary fiber, to anaerobic fermentation using human fecal bacteria.

They found that gut bacteria, such as bifidobacteria and lactic acid bacteria, chow down on chocolate, producing compounds that are anti-inflammatory. When the body absorbs these compounds, inflammation of cardiovascular tissue is reduced as is the risk of stroke. Next step is to progress beyond simulations.
 

Wrap Up 

Now for the sad news. Enjoy your chocolate, with its added sugar and fat, but don’t expect much in the way of flavonoids and other polyphenols. Those compounds are generally destroyed in processing. The cocoa flavanol drink used in the cognitive studies was produced specially by the candy maker, Mars, Inc., a research collaborator that markets a cocoa-flavanol product, CocoaVia.

General steps in producing cocoa and chocolate
(www.food-info.net/images/chocolateflowsheet.jpg)
Mars, Inc. will also partner with the National Institutes of Health, Brigham and Women’s Hospital and the Fred Hutchinson Cancer Research Center in a 5-year study to evaluate the role of flavanols in reducing the risk of heart attack, stroke and death from cardiovascular disease in 18,000 women and men nationwide. That study kicks off in 2015.

So, nibble away at your dark chocolate, which usually has more flavanols, and stay tuned. And thanks for stopping by. I hope it was of interest.

P.S.

Work reviewed in blog post…
Hypertension journal paper and Berkeley Wellness article on 2012 cognitive function study:
hyper.ahajournals.org/content/60/3/794.full
www.berkeleywellness.com/healthy-eating/nutrition/article/chocolate-brain
Nature Neuroscience paper and Time article on 2014 cognitive function study:
www.nature.com/neuro/journal/vaop/ncurrent/full/nn.3850.html
time.com/3540703/cocoa-memory-loss-flavanols-aging-hippocampus/?xid=newsletter-brief
American Chemical Society press release and PDF package on Louisiana State study:
www.acs.org/content/acs/en/pressroom/newsreleases/2014/march/the-precise-reason-for-the-health-benefits-of-dark-chocolate-mystery-solved.html
graphics8.nytimes.com/packages/pdf/health/ACS.pdf

Related material…
Journal of Agricultural and Food Chemistry paper and Science Daily article on Virginia Tech study that examined specific flavanols to combat obesity and diabetes:
pubs.acs.org/doi/abs/10.1021/jf500333y
www.sciencedaily.com/releases/2014/04/140402110000.htm
Collection of links to papers and articles on chocolate’s health benefits: cocoarunners.com/explore/chocolate-health/
Cacao comeback in Puerto Rico:
www.ars.usda.gov/research/projects/projects.htm?accn_no=423953
bespokemagazineonline.com/cocoas-comeback/

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