A recent study in the Journal of Proteome Research suggests that eating a few pieces of dark chocolate every day may improve the metabolic response of people who report feeling highly stressed.

For this study, the researchers investigated the metabolic response in a group of 30 healthy adult volunteers who were asked to consume two portions of 20g of dark chocolate every day for up to 14 days.

The volunteers were separated into 2 groups based on whether they exhibited low or high anxiety traits.

To assess metabolic response (specifically energy metabolism and microbial activity in the gut), the researchers analyzed urine and blood plasma given by each volunteer during three test days at the beginning, the middle and the end of the 14 day period.

After the 14-day study period, the researchers found that:

• Subjects with higher anxiety trait had a distinct metabolic profile, which was indicative of a different energy and hormone metabolism, and gut microbe activity.

• Dark chocolate reduced the amount of stress hormone cortisol and catecholamines in the urine.

• Dark chocolate also partially normalized stress-related differences in energy metabolism and gut microbial activities.

So what do these findings even mean?

Well, according to the researchers, “The study provides strong evidence that a daily consumption of 40 g of dark chocolate during a period of 2 weeks is sufficient to modify the metabolism of free living and healthy human subjects, as per variation of both host and gut microbial metabolism.”

The researches also maintained that…

“Consuming dark chocolate daily can positively impact the metabolism of people that report having high-stress levels.”

It comes as no surprise that this study was conducted by the Nestlé Research Center in Lausanne, Switzerland.

I’m not saying that the results are biased. Obviously someone (or some company) needs to conduct the research.

However, what isn’t clear is what type of dark chocolate was used in the study. I can only assume that is was Nestlé’s on brand that was given to subjects. If that’s the case, then that’s a bit of good news for a big food conglomerate that doesn’t necessarily consider the health-promoting properties of its products to be the greatest priority.

How Does Chocolate Reduce Stress?

Cacao (the main component of chocolate) has been treasured for centuries. In fact, the some ancient civilizations even used cacao as currency!

Eating chocolate can help reduce because of its numerous effects on our brain and nervous system.

For instance, chocolate increases the levels of endorphins released into the brain, which work to lessen pain and decrease stress.

Another common neurotransmitter affected by chocolate is serotonin. Serotonin is known as an anti-depressant. One of the chemicals which causes the release of serotonin is tryptophan found in, among other things, chocolate.

One of the more unique neurotransmitters released by chocolate consumption is phenylethylamine. This compound causes changes in blood pressure and blood-sugar levels leading to feelings of excitement and alertness. It works in much the same way as do amphetamines to increase mood and decrease depression, but it does not result in the same tolerance or addiction.

Phenylethylamine is also called the “love drug” because it causes your pulse rate to quicken, resulting in a similar feeling to when someone is in love. However, this could also be caused by the slight amount of caffeine naturally found in cacao.

Another interesting compound found in chocolate is the lipid anandamide. Anandamide is unique due to its resemblance to THC (tetrahydrocannabinol), a chemical found in marijuana.

Both activate the same receptor which causes the production of dopamine, a neurotransmitter which leads to feelings of well being that people associate with a high. Normally, anandamide, found naturally in the brain, breaks down very rapidly. However, besides increasing the levels of anandamide, chocolate also contains other chemicals which work to slow the breakdown of the anandamide, thus extending the feelings of well-being.

Even though the anandamide in chocolate helps to create feelings of elation, the effect is not the same as the THC in marijuana. THC reacts with receptors more widely dispersed in the brain and is present in much larger amounts. It would take twenty-five pounds of chocolate to achieve a similar high to that of marijuana.

A more well known chemical found in chocolate is theobromine. Besides having properties that can lead to mental and physical relaxation, it also acts as a stimulant similar to caffeine. It can increase alertness as well as cause headaches. There is much debate as to whether or not caffeine even exists in chocolate. Some scientists believe that it is the less potent theobromine which is solely responsible for the caffeine-like effects.

How to Choose the Healthiest Chocolate

Finding the healthiest chocolate can be a daunting task, especially considering the overwhelming number of options. But in general, there are a few things you want to look for.

• Choose a dark chocolate that is at least 70% cacao. This is means that the chocolate is lower in sugar and dairy products.

• Choose a chocolate that contains no dairy. You can find ones that use cocoa butter and rice milk instead.

• Choose a chocolate that is organic and fair trade if possible.

• Choose raw chocolate whenever possible. All the benefits we talked about above are lessened when cacao is heated and processed. I personally love raw cacao nibs/powder. They can easily be added to a smoothie or used to make a raw dessert.

If you don’t have access to the raw cacao from a health food store, then you can also try grabbing these ones. These are my 3 favourite types of commercially available chocolate.

• Terra Nostra – organic and equitable trade chocolate. They also have a rice milk chocolate.

• Theobroma Chocolat - 100% organic and absolutely delicious. I like the dark and coconut flavours.

• SOMA – local to Toronto and 100% organic, I usually grab a truffle or set of 85% dark chocolate squares any time I pass by.

Got any other chocolate you’d like to share? I’d love to hear your thoughts in the comments.

Reference:

“Metabolic Effects of Dark Chocolate Consumption on Energy, Gut Microbiota, and Stress-Related Metabolism in Free-Living Subjects.”Francois-Pierre J. Martin, Serge Rezzi, Emma Per-Trepat, Beate Kamlage, Sebastiano Collino, Edgar Leibold, Jrgen Kastler, Dietrich Rein, Laurent B. Fay and Sunil Kochhar. Journal of Proteome Research, 2009

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