In the past, studies have shown that cocoa flavanol consumption can lower the risk of developing dementia, and this latest science supports the notion that regular consumption of dark chocolate may act directly on brain structure and function by protecting neurons from injury, improving metabolism and their interaction with the molecular structure responsible for memory.
To conduct this research, the study team assembled a cohort of 90 elderly participants with mild cognitive impairment. Participants were randomized to drink a dairy-based cocoa flavanol mixture containing concentrations ranging from 990 mg (highest) to 520 mg (intermediate) or 45 mg (lowest), daily for eight weeks. The diet was restricted to eliminate other sources of flavanols from foods and beverages other than the dairy-based cocoa drink. Cognitive function was examined by neuro-psychological tests of executive function, working memory, short-term memory, long-term episodic memory, processing speed and global cognition.
The researchers found that tests to assess working memory and the ability to relate visual stimuli to motor responses were significantly improved in the high cocoa flavanol group as compared to the lowest intake group. The study also determined that participants drinking higher levels of flavanol drinks had significantly improved cognitive scores than those participants drinking lower levels. Most important, high and intermediate intake group members showed improved markers for insulin resistance, oxidative stress and blood pressure relative to the low consumption participants.
The study authors concluded “This study provides encouraging evidence that consuming cocoa flavanols, as a part of a calorie-controlled and nutritionally-balanced diet, could improve cognitive function… the positive effect on cognitive function may be mainly mediated by an improvement in insulin sensitivity.” Prior research bodies suggest consuming the equivalent of one square of dark chocolate (minimum 85 percent cocoa flavanols) daily or supplementing with 500 to 1,000 mg of a standardized shake or capsule to improve memory and lower the risk of dementia during aging.