For some people, indulging in a daily chocolate habit could be all it takes for a better-working brain.
A small new study conducted by Harvard researchers shows that drinking two cups of hot chocolate a day for 30 days was linked with improved blood flow to the brain and better scores on memory and thinking skill tests for elderly people with impaired blood flow.
Researchers noted that memory and thinking skills and brain blood flow are linked because of a concept called "neurovascular coupling."
"We're learning more about blood flow in the brain and its effect on thinking skills," study researcher Farzaneh A. Sorond, M.D., Ph.D., of Harvard Medical School, said in a statement. "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."
The study, published in the journal Neurology, included 60 people over age 65, with an average age of 73. Of those people, 18 started the study off with impaired blood flow. Half of the study participants drank antioxidant flavonol-rich hot cocoa (dark chocolate is high in flavonols), while the other half drank hot cocoa with low levels of flavonols.
Researchers found that after the month-long study -- during which participants were not permitted to eat any other kinds of chocolate -- the ones who had the impaired blood flow experienced an improvement in blood flow by 8.3 percent. And both the flavonol-rich and flavonol-poor hot cocoas seemed to have this effect.
"From a clinical aspect, this study suggests that vascular effects of cocoa may not be due to its flavanol content," wrote Paul Rosenberg, M.D., and Can Ozan Tan, Ph.D., in a related editorial. "There has been considerable interest in the development of polyphenols including flavanols as vascular interventions for neurodegenerative disease either as single chemical entities (such as epicatechin and resveratrol) or as components of nutriceuticals such as cocoa, but the results of this pilot trial argue against this hypothesis."
Of course, chocolate isn't the only food that could give your brain a boost. Click through the slideshow for some other foods that could do your noggin' good: