COCOA FLAVONOLS BOOST BRAIN OXYGENATION, COGNITION AMONG ADULTS
The brains of healthy adults recovered faster from a mild vascular challenge and performed better on complex tests if the participants consumed cocoa flavanols beforehand, researchers report in the journal Scientific Reports. In the study, 14 of 18 participants saw these improvements after ingesting the flavanols.
Previous studies have shown that eating foods rich in flavanols can benefit vascular function, but this is the first to find a positive effect on brain vascular function and cognitive performance in young healthy adults, said Catarina Rendeiro, a researcher and lecturer in nutritional sciences at the University of Birmingham who led the research with University of Illinois at Urbana-Champaign psychology professors Monica Fabiani and Gabriele Gratton, Science Daily reported.
"Flavanols are small molecules found in many fruits and vegetables, and cocoa, too," Rendeiro said. "They give fruits and vegetables their bright colors, and they are known to benefit vascular function. We wanted to know whether flavanols also benefit the brain vasculature, and whether that could have a positive impact on cognitive function."
The team recruited adult nonsmokers with no known brain, heart, vascular or respiratory disease, reasoning that any effects seen in this population would provide robust evidence that dietary flavanols can improve brain function in healthy people. The team tested the 18 participants before their intake of cocoa flavanols and in two separate trials, one in which the subjects received flavanol-rich cocoa and another during which they consumed processed cocoa with very low levels of flavanols. Neither the participants nor researchers knew which type of cocoa was consumed in each of the trials. This double-blind study design prevents researchers' or participants' expectations from affecting the results.
About two hours after consuming the cocoa, participants breathed air with 5% carbon dioxide -- about 100 times the normal concentration in air. This is a standard method for challenging brain vasculature to determine how well it responds, Gratton said. The body typically reacts by increasing blood flow to the brain, he said. "This brings in more oxygen and also allows the brain to eliminate more carbon dioxide," he said.