A recent study in the journal Neurology provides some exciting evidence on potential cognitive benefits of drinking cocoa. The study of 60 older adults showed that cocoa consumption led to cognitive benefits for individuals with impaired connections between blood vessels and brain tissue in particular.
This integration of blood vessels and brain tissue (known as neurovascular coupling) has been recognized as an important factor in cognitive health, with poor integration being associated with neurodegenerative diseases such as vascular cognitive impairment and Alzheimer’s Disease.
Of the 60 participants (average age of 73), at the start of the study, 17 showed signs of poor neurovascular coupling. This poor neurovascular coupling was also associated with poorer performance on a working memory task compared with participants with no impairment of neurovascular coupling. Working memory is also known as short-term memory and refers to the part of memory that is involved with temporarily storing.
After drinking two cups of cocoa a day for a month (with no additional chocolate intake), 88 percent of the participants with impaired neurovascular coupling at the start of the study showed an improvement in their neurovascular coupling. Of those participants with no neurovascular coupling impairment, 37 percent showed improvement in their neurovascular coupling after a month of drinking cocoa as well. Among the impaired neurovascular coupling group, drinking cocoa was also associated with improved cognitive performance on the Trails-B Test, which measures executive functioning, mental flexibility, and processing speed.
Study participants were also given two different cocoas: one high in flavanols and one low in flavanols. Cocoa flavanols were the compounds that were suspected to be responsible for the positive health benefits of cocoa and chocolate. Surprisingly, there were no differences observed between participants who drank the different cocoas. This suggests that the benefits from drinking cocoa were due to compounds in cocoa that still need to be identified.
This study also describes a technological innovation that holds great promise for diagnosing neurovascular coupling. Instead of using expensive MRIs, which has been common in past studies, these researchers were able to employ much less expensive ultrasounds to diagnose the degree of neurovascular coupling. With this technological innovation, identifying poor neurovascular coupling becomes easier and cheaper than before, holding out the promise that screening for neurovascular coupling can become a common diagnostic procedure that might allow poor neurovascular coupling to be treated before it leads to negative clinical consequences.
Sorond FA, Hurwitz S, Salat D, et al. Neurovascular coupling, cerebral white matter integrity, and response to cocoa in older people. Neurology. (2013) DOI: 10.1212/WNL.0b013e3182a351aa