Drinking Hot Cocoa May Help Keep Alzheimers At Bay

BOSTONOlder adults with impaired blood flow to their brains who drink about 2 cups of hot cocoa a day may lessen their risk of developing dementia, according to a new study published in the journal Neurology. The finding suggest a strong correlation between neurovascular coupling and cognitive function, and both can be improved by regular cocoa consumption in individuals with baseline impairments.

Researchers from Brigham and Women's Hospital investigated the relationship between neurovascular coupling and cognitive function in elderly individuals with vascular risk factors to determine whether neurovascular coupling could be modified by cocoa consumption.

The study involved 60 people with an average age of 73 years who did not have dementia. The participants drank two cups of hot cocoa per day for 30 days and did not consume any other chocolate during the study. They were given tests of memory and thinking skills. They also had ultrasounds tests to measure the amount of blood flow to the brain during the tests.

Of the 60 participants, 18 had impaired blood flow at the start of the study. Those people had an 8.3% improvement in the blood flow to the working areas of the brain by the end of the study, while there was no improvement for those who started out with regular blood flow. Participants with impaired blood flow also improved their times on a test of working memory, with scores dropping from 167 seconds at the beginning of the study to 116 seconds at the end. There was no change in times for people with regular blood flow. A total of 24 participants also had MRI scans of the brain to look for tiny areas of brain damage. The scans found that people with impaired blood flow were also more likely to have these areas of brain damage.

Half of the study participants received hot cocoa that was rich in the antioxidant flavanol, while the other half received flavanol-poor hot cocoa. There were no differences between the two groups in the results.

"We're learning more about blood flow in the brain and its effect on thinking skills," said study author Farzaneh A. Sorond, MD, PhD, of Harvard Medical School in Boston and a member of the American Academy of Neurology. "As different areas of the brain need more energy to complete their tasks, they also need greater blood flow. This relationship, called neurovascular coupling, may play an important role in diseases such as Alzheimer's."

"More work is needed to prove a link between cocoa, blood flow problems and cognitive decline," said Paul B. Rosenberg, MD, of Johns Hopkins School of Medicine in Baltimore, who wrote an editorial accompanying the study. "But this is an important first step that could guide future studies."