Is cocoa the key to preventing Alzheimer’s disease?

  Although the most important risk factor for Alzheimer’s disease (AD) is age, AD is not a normal part of aging. The most common early manifestation is difficulty remembering the latest things learned. 60-80% of dementia in the United States is attributed to Alzheimer’s disease.  In the past, chocolate was not considered a health food. But chocolate contains nutrients that maintain brain health and prevent age-related neurodegenerative diseases such as Alzheimer’s disease, as cited in a recent review article published in the JournalofAlzheimer’sDisease. Cocoa extracts contain high levels of polyphenolic substances. Studies suggest that chocolate and cocoa can reduce the risk of heart disease. In particular, polyphenols called flavanolanes have been shown to have antioxidant effects and to reduce cellular damage caused by heart disease and to thin the blood. in June, MedicalNewsToday reported on an article suggesting that consuming 100g of chocolate daily may reduce the risk of heart disease and stroke. In addition, several studies have suggested that cocoa extract is beneficial in reducing age-related cognitive dysfunction and helping the brain resist aging.  The lead author of the article, Dr. Giulio Maria Pasinetti, a neurologist at the Icahn School of Medicine at Mount Sinai in New York, concluded in his earlier studies that the specific structure of cocoa extract is protective in animal models of Alzheimer’s disease.  In these studies, cocoa extracts helped reduce the production and scavenge harmful proteins that accumulate in the brain, such as beta-amyloid and abnormal tau protein aggregates. Thus, emerging biomedical research evidence and new clinical translational studies are of great interest for cocoa as a botanical source for maintaining and promoting health, especially for the brain.  In the review the authors report that it is estimated that approximately 35.6 million people had Alzheimer’s disease in 2010, and that this number could double by 2030. Currently available treatments only alleviate cognitive decline and do not slow the progression of the disease.  Cocoa extracts and the blood-brain barrier: The authors report that studies have shown that dietary polyphenols are able to cross the blood-brain barrier and reach areas of the brain that are critical to the progression of Alzheimer’s disease. For example, we know that a polyphenol metabolite, pentoxifylline-3-O-glucoside, is able to cross the BBB [blood-brain barrier] and accumulate in the brain, where it can modulate neuropathogens. During the fight against abnormal aggregation of harmful proteins (e.g., of β-amyloid), cocoa polyphenols are able to protect against neuronal loss in the brain and, therefore, may contribute to the maintenance of functional connections between nerve cells.  In order to take full advantage of the potential health components in cocoa extracts, Dr. Pasinetti and colleagues propose a multi-disciplinary collaboration that includes cocoa producers, wholesalers and biomedical researchers. They believe there is a gap of at least one million tons between global cocoa supply and demand, and estimate that this gap will widen in the near future, as climate change, growth and pests and diseases affect cocoa production. New varieties of cocoa are now more resistant to disease and more productive. In studies and interviews on production like this one, the authors claim that the gap between cocoa supply and demand is narrowing.  The authors believe that the mechanisms by which cocoa extracts affect cognition should be fully understood and that more research is needed. Finally, they suggest that the extraction and analysis of cocoa polyphenols should be standardized, concluding, “A successful translational study of cocoa extracts in a clinical setting requires a concerted research effort to explore cocoa extract resources, improve standard methods for the quantitative determination of cocoa polyphenols, and investigate cocoa processing, bioavailability, and biological responses to cocoa polyphenols. “