Drinking cocoa can increase your mental agility, study finds

Drinking cocoa can increase your mental agility thanks to the presence of flavanols – chemicals that are abundant in cocoa beans.

British and American researchers found that healthy adults performed better cognitive tasks if the participants consumed a cocoa drink containing high levels of flavanols.

After drinking flavanol-rich cocoa, participants produced a faster and greater increase in blood oxygenation in the frontal cortex – a region of the brain that plays a key role in cognition and decision making – which helped them accomplish these tasks.

Flavanols are antioxidants and are abundant in tea, red wine, blueberries, apples, pears, cherries, and peanuts, as well as in the seeds of the cocoa tree – cocoa beans.

By fortifying supermarket cocoa with flavanols, food producers could help us increase brain-boosting plant nutrients in our diets.

They are already well known for their beneficial effects on cardiovascular health, a 1993 study showing a negative relationship between total intake and coronary heart disease.

But this new study is the first to find a positive effect of flavanols on cerebrovascular function and cognitive performance in healthy young adults, the researchers say.

“Flavanols are small molecules found in many fruits and vegetables, as well as in cocoa,” said study author Dr Catarina Rendeiro of the University of Birmingham in the UK.

“They give fruits and vegetables their bright colors and they are known to be beneficial for vascular function.

“We wanted to know if the flavanols were also beneficial for the cerebral vascular system and if this could have a positive impact on cognitive function.

Working with psychology professors at the University of Illinois at Urbana-Champaign in the United States, Dr. Rendeiro recruited 18 adult males between the ages of 18 and 40.

All 18 participants were non-smokers with no known brain, heart, vascular or respiratory disease.

The researchers said, “Women were excluded from the study to ensure a more homogeneous sample and to minimize the impact of hormonal fluctuations during the menstrual cycle on vascular outcomes.

The team tested the participants before their consumption of cocoa flavanols and in two separate trials – one in which the subjects received cocoa rich in flavanols and another in which they consumed processed cocoa with very low levels of flavanols.

The researchers used a “double-blind” design – in which neither the participants nor the researchers knew what type of cocoa was consumed in each of the trials – to prevent any expectations from affecting the results.

About two hours after consuming the cocoa, the participants underwent a standard procedure to challenge the blood flow to the brain.

This involves breathing in 5% carbon dioxide – about 100 times the normal concentration in the air – producing an effect called hypercapnia.

This is a standard method for challenging brain vasculature to determine how well it is responding.

“The body generally responds by increasing blood flow to the brain,” Gratton said.

“It brings in more oxygen and also allows the brain to remove more carbon dioxide.”

Non-invasive near infrared spectroscopy – a technique that uses light to capture changes in blood oxygenation levels – was then used to track increases in oxygenation in the frontal cortex and “ see how well the brain defends itself against excess CO2 ”.

The frontal cortex plays a key role in planning, regulating behavior and making decisions.

Each participant underwent the CO2 test before and after drinking a cocoa drink on two occasions – and on one of these occasions the drink was fortified with flavanols.

After the test, participants were asked to perform a number of progressively complex cognitive tests that required them to deal with sometimes contradictory or competing demands.

The cognitive tests were based on a modified version of the Stroop task – which involves identifying whether there is a mismatch between the name of a color and the ink it is printed in (e.g. the word “ purple ” appearing in green ink).

Most participants had a stronger and faster cerebral oxygenation response after exposure to cocoa flavanols than they did when starting or after consuming cocoa without flavanols, the researchers found.

“Peak oxygenation levels were more than three times higher in high flavanol cocoa than low flavanol cocoa, and the oxygenation response was about a minute faster,” said Dr Rendeiro.

After ingesting the cocoa flavanols, participants also performed better on the more difficult cognitive tests, correctly solving problems 11% faster than when they started or when consuming cocoa with reduced flavanols.

However, there was no measurable difference in performance on the easier tasks.

“This suggests that flavanols might only be beneficial during more difficult cognitive tasks,” said Rendeiro.

“Our results showed a clear benefit for the participants taking the flavanol-fortified drink – but only when the task became complicated enough,” said Dr Rendeiro.

“We can relate this to our results on improving blood oxygenation – if you are challenged more, your brain needs improved blood oxygen levels to handle that challenge.

Participants varied in their responses to cocoa flavanols, the researchers found, and although most people benefited from the flavanol intake, there was a small group that did not.

Four of the 18 participants had no significant difference in the brain’s oxygenation response after consuming flavanols, and their test performance did not improve.

But these four participants already had the highest oxygenation responses at baseline.

“This may indicate that those who are already fairly fit have little room for improvement,” said Dr Rendeiro.

“Overall, the results suggest that improvements in vascular activity after exposure to flavanols are related to improved cognitive function.

The study was published in Scientific Reports.