Chocolate: Habitual Consumption 'Positively Associated' With Brain Function

23 Feb 2016 --- Brain health benefits of chocolate have been discovered in new research published in the journal Appetite— the first cohort study to examine associations between longer-term chocolate eating and brain function, according to researchers.

Prior studies have shown chocolate and cocoa flavanols can improve cardiovascular health, but less is known about ways chocolate impacts human cognition. The present study aimed to learn more about the treat's neurocognitive benefits.

The research was undertaken by Dr Georgie Crichton, of the Alliance for Research in Exercise, Nutrition and Activity (ARENA) at the University of South Australia, in collaboration with the University of Maine and the Luxembourg Institute of Health.

"Previous research has focused on dark chocolate (as it is higher in cocoa flavanols – thought to be responsible for the beneficial effect), but our research has included milk chocolate consumers. So good news if you prefer milk over dark!" Crichton told NutritionInsight.

Data was obtained from the sixth wave of the Maine-Syracuse Longitudinal Study (MSLS) – a study which has tracked 1,000 people over 30 years, measuring a whole range of health variables. Participants living in Syracuse, N.Y., were measured for dietary intake and risk factors for cardiovascular disease. For the dietary portion, the contributors answered a questionnaire that measured how frequently they consumed a list of foods, including meat, rice and pasta, fruit, vegetables, chocolate, other snack-type foods, as well as beverages like water, coffee, and alcohol. The answers ranged from never to once or more per day.

Curious to see if cognitive performance predicted chocolate consumption, researchers performed a second analysis on a sample of participated who completed the dietary questionnaire, as well as cognitive tests given during earlier waves of MSLS. However, the results found no significant associations between chocolate intake and performance.

Crichton explains: “These relations were not attenuated with statistical control for cardiovascular, lifestyle and dietary factors. This means that irrespective of factors including age, sex, education, cholesterol, glucose, blood pressure, total energy and alcohol intake, the relationship between chocolate intake and cognition remained significant.”

To measure for cognitive function, participants were given a series of tests designed to measure a wide range of cognitive domains: visual-spatial memory and organization, scanning and tracking, verbal episodic memory, and working memory. The Mini-Mental State Examination was also included to measure for mental status — high scores indicating better performance.

When combining dietary intake with cognitive tests, individual demographics, and physical health assessments, researchers found chocolate consumption was positive associated with cognitive performance "irrespective of other dietary habits." The finding held up even when researchers adjusted for participant's cardiovascular risk factors, including total and LDL-cholesterol, glucose levels, and hypertension.

Some studies suggest there's an equal amount of methylxanthines in chocolate, a combination of caffeine and theobromine that's been associated with improving alertness and cognitive function. Nevertheless, an overwhelming amount of chocolate-related research shows preference for dark chocolate as it tends to have higher levels of flavanols: one hundred grams of dark chocolate contains approximately 100 mg of flavanols, compared to 15 mg for the same amount of milk chocolate.

“Previous research has mostly examined the acute effects of increasing chocolate consumption on cognition, (i.e. performance) immediately after consuming a chocolate bar or cocoa-rich drink, with a focus on dark chocolate. Our research has looked at habitual intakes, and also included milk chocolate. So although milk chocolate is lower in cocoa flavanols than dark chocolate, the findings suggest that there may also be some benefit to brain health from consuming milk chocolate”.

"It is evident that nutrients in foods exert differential effects on the brain. As has been repeatedly demonstrated, isolating these nutrients and foods enables the formation of dietary interventions to optimize neuropsychological health," the researchers wrote. "Adopting dietary patterns to delay or slow the onset of cognitive decline is an appropriate avenue, given the limited treatments available for dementia. The present findings support recent clinical trials suggesting that regular intake of cocoa flavanols may have a beneficial effect on cognitive function, and possibly protect against normal age-related cognitive decline."

In the future, researchers suggest there be "longer-term clinical trials to shed further insight into this association between chocolate," cocoa flavanols, and neuropsychological health. They're also interested to see how the amounts of chocolate people eat affects cognition, and the effects of when foods high in flavonoids are consumed in combination.

Given the results of this research, Dr Crichton is keen to emphasize that chocolate consumption should just be one part of a healthy, balanced diet. “Of course chocolate intake should be considered within an overall healthy eating pattern, with consideration given to total energy intake and an individual’s energy needs,” she says.

by Kerina Tull