The brain-health promise of chocolate and cocoa just got a big boost.
Already, lab studies show that cocoa boosts brain blood flow and helps protect brains against oxidation and inflammation ... two key drivers of age-related dementia and aspects of Alzheimer's disease.
Population studies consistently suggest that proper diet and lifestyle probably help protect against dementia, as well as Parkinson's and Alzheimer's diseases.
Better brain health is statstically linked to higher intake of antioxidant-rich herbs, spices, fruits and vegetables, cocoa, and tea.
And lab studies indicate that most of these benefits come from two families of “antioxidants”: polyphenols and carotenoids. (see our sidebar, “Food-borne ‘antioxidants'”.)
Cocoa and tea abound in polyphenol-class compounds called flavanols, which may deliver unique vascular and brain benefits … with cocoa's broader flavonol blend showing special promise.
Importantly, that clinical test confirmed that these benefits came from the unique mix of flavonols that abound in natural, non-alkalized cocoa, called catechins and procyanidins.
Most cocoa makers treat theirs with alkali – the process known as “Dutching”, used to cut cocoa's slight bitterness – which destroys some 90 percent of its healthful flavanols.
a well-meant, misleading misnomer
Whole plant foods abound in so-called “antioxidants” … primarily carotenes (carrots, squash, peppers, and wild salmon) and polyphenols, which occur in most plant foods.
The richest polyphenol sources include raw (non-alkalized / non-“Dutched”) cocoa, spices, herbs, berries, plums, prunes, tea, coffee, extra virgin olive oil, onions, beans, and whole grains.
Among other likely beneficial effects, polyphenols' known “nutrigenomic” influences on gene switches and signals tend to reduce unhealthful levels of oxidation and inflammation.
The apparent health benefits of plant foods rich in carotenes and polyphenols almost certainly flow from these nutrigenomic effects, rather than from direct antioxidant effects in the body.
Polyphenols' nutrigenomic effects moderate inflammation and stimulate the body's own antioxidant network … enzymes, lipoic acid, CoQ10, melatonin, and vitamins C and E.
That general rule applies to the polyphenols in cocoa, which exert unusually powerful antioxidant effects in test tube studies, but not in the body (Scheid L et al. 2010).
Evidence linking diets rich in carotenes and polyphenols to apparently beneficial nutrigenomic effects may well explain why such diets are associated with a lower risk of Alzheimer's and other degenerative diseases.
More recently, clinical research has linked cocoa's flavanols to enhanced brain health.
Those signs were affirmed last year in an evidence review from the French Medical Research Institute, which came to this conclusion: “Cocoa powder and chocolate … display several beneficial actions on the brain.” (Nehlig A 2012)
And last month, an international team reported finding cocoa-flavanol effects that should protect the brain in an important way that hadn't yet been demonstrated.
U.S. - Italy study adds to cocoa's brain-health potential
The researchers hailed from Philadelphia‘s Temple University, Washington's Georgetown University, and Italy's University of L'Aquila, University of Siena, and Sbarro Institute.
They tested cocoa flavonols on human brain cells burdened by the beta amyloid plaque linked to Alzheimer's, and detected critical benefit (Cimini A et al. 2013).
The international team found that cocoa flavonols activated the “survival pathway” for a critical brain chemical called BDNF.
BDNF fosters growth of brain-cell networks and helps brain cells survive stresses.
The findings hold important implications for preventing and/or ameliorating dementia and neurodegenerative diseases.
Lead author Annamaria Cimini, from the University of L'Aquila, put it this way: “Our studies indicate for the first time the cocoa polyphenols do not act only as mere antioxidant but they, directly or indirectly, activate the BDNF survival pathway counteracting neuronal death.” (SHRO 2013)
“Understanding the preventive potential and the mechanism of action of functional food may provide a means to limit cognitive impairment progression”, added Antonio Giordano, M.D., Ph.D., of Temple University and the Sbarro Institute (SHRO 2013).
Most dark chocolate is made from natural cocoa and will be high in flavonol. But beware … the term “dark chocolate” has no legal definition in the U.S. … look for chocolate that's at least 65 percent cocoa solids.
And look for cocoa powder that says “natural” and/or does not list alkali as an ingredient.
Sadly, even some organic cocoa powders have been alkalized.
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