Cocoa for cognition: Study proposes how to assess what exactly in chocolate may give brains a boost

The potential cognitive benefits of eating chocolate is an enduring topic among researchers and consumers alike because, well, it’s chocolate.

Scientific literature backing this potential continues to build, ranging from a 2012 paper in The New England Journal of Medicine ​which linked a country’s level of chocolate consumption and its total number of Nobel laureates​​, to a clinical trial from last year​​ which looked at how cocoa flavanols may enhance brain health benefits of exercise.

But given the high degree of variation in composition found in commercial cocoa and chocolate products (geographical origin, fermentation, further processing, and so forth), “it is amazing to see how little attention is paid in many studies to proper characterization of test samples,” ​argued researchers from the University of Antwerp, Belgium, in a paper​​ published in Planta Medica​ this year.

“In many cases, only the amount of cocoa flavonols is mentioned, and in fewer cases the levels of caffeine and theobromine.”​

“This creates a high degree of uncertainty about which components might be responsible for positive results and if negative results may be due to poor quality and low levels of biologically active ingredients of the test materials or cocoa/chocolate products used,”​ they added.

The ‘mood pyramid’​

The researchers conducted a systematic review, in which they reviewed studies published so far that involved chocolate consumption and measured a cognitive health-related outcome.

They sifted through study databases like SciFinder and PubMed using the search terms ‘cocoa,’ ‘mood,’ and ‘cognition.’ The goal was to analyze the pool of studies from a phytochemical lens, looking at the various biologically active compounds found in plants.

So what exactly in chocolate is responsible for a mood boost? It’s still vague, for now, but the researchers argued that their analysis is the first to structurally organize all existing studies on chocolate and mood, helping them pinpoint different levels and factors of which cocoa and cocoa-derived products like chocolate may improve mood.

This led to the creation of a ‘mood pyramid’ for use in future studies on cocoa and chocolate. At the top of the pyramid is the orosensory properties, which is about the mouthfeel, flavor, and overall experience of eating chocolate.

“It has been established that also the orosensory properties of chocolate can at least in part explain the desire to ingest chocolate and can contribute to mood effects,” ​they wrote. This includes products like hot coco, but not capsules of individual compounds found in cocoa.

As we go down on the pyramid, the psychopharmacological actions of cocoa and chocolate become more specific. This means, while a pleasurable orosensory experience can be found from other food items found in nature (sugar, savory potato chips, and more), the bottom of the pyramid is for cocoa flavanols, which are specific to cocoa.

Future studies should characterize chocolate samples in more detail​

Future studies on cocoa that are in vitro​ (in a petri dish) or in vivo ​(an animal or human clinical trial) should use an intervention product that is phytochemically characterized in much more detail than is common practice today, they argued.

Depending on geographical origin and processing, the phytochemical composition of cocoa and chocolate can be highly variable.

“Only by comparing different test samples with different analytical profiles can the role of the various constituents of cocoa and chocolate be unraveled and potential synergistic effects be rationalized,”​ they wrote.

Source: ​Planta Medica​
Published online ahead of print, DOI: 10.1055/a-0588-5534
“Mood Components in Cocoa and Chocolate: The Mood Pyramid”​
Authors: Emmy Tuenter, Kenn Foubert, Luc Pieters