Serotonin & Dopamine: The Neurological Benefits of Chocolate

Chocolate Cake with Mocha Frosting
(Recipe courtesy of Ina Garten)

• 12 tablespoons (1 1⁄2 sticks) unsalted butter, at room temperature
• 2 cups sugar

• 1 tablespoon pure vanilla extract
• 
3 extra-large eggs, at room temperature
  
• 1 3⁄4 cups all-purpose flour
• 
1 teaspoon baking soda
• 
1 teaspoon kosher salt
• 
2/3 cup hottest tap water
• 
2/3 cup unsweetened cocoa powder, such as Pernigotti
• 1 teaspoon instant espresso powder
• 2/3 cup half-and-half Mocha Frosting (see recipe)

Preheat the oven to 350 degrees. Grease a 9 × 13 × 2-inch baking pan. Line with parchment paper, then grease and flour the pan.

Place the butter and sugar in the bowl of an electric mixer -fitted with the paddle attachment and beat on medium speed for 4 to 5 minutes, until light and fluffy, scraping down the bowl. On medium speed, add the vanilla, then beat in the eggs, one at a time, until incorporated and the batter is smooth.

Sift the flour, baking soda, and salt together in a medium bowl. In another bowl or a liquid measuring cup, whisk together the hot water, cocoa powder, and espresso powder until smooth. Add the half-and-half and whisk until smooth. With the mixer on low, add the flour and chocolate mixtures alternately in thirds, starting and ending with the flour. With a rubber spatula, scrape down the bowl to be sure the batter is well mixed. Pour the batter into the prepared pan, smooth the top, and bake for 25 to

35 minutes, until a cake tester inserted in the center comes out clean. Cool completely in the pan. Turn out onto a flat platter or board and frost the top with the mochafrosting. Cut in squares and serve.

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I’m sure right now the only thing you think are thinking about after having baked this amazingly delicious chocolate cake is “Wow, I cannot wait to try a piece!” The smell of your kitchen is intoxicating and your mouth is salivating. At this point, any thoughts about the nutritional content or origins of the ingredients you used while baking are nonexistent. However, this cookbook is here to provide not only the “how to” behind cooking or baking, but also the historical background and science behind the ingredients you are consuming.
For this recipe we will focus on chocolate. With its roots traced back to the ancient Mayans, chocolate does more than satisfy your taste buds. This unique ingredient calls our attention to the idea of neural signaling. We no longer can just focus on the energy and caloric function that food provides. Rather, we must look beyond the surface and ask, what other roles does this ingredient play in the body? We now turn to examine both the history of chocolate and the future directions we must take to better understand how this ingredient not only affects our stomachs, but also our brains.

The earliest documented records of chocolate begin with the Central American Mayans who “not only consumed chocolate but revered it” (History Of Chocolate). In Mayan culture, chocolate was readily available and found its way into almost every meal. This ingredient was viewed as “magical” in that it possessed divine properties. Fast forward to the American colonies where chocolate was introduced in 1641 when it arrived by boat from Spain to Florida. For most of the 17^thcentury, chocolate was enjoyed as a “fashionable drink that was believed to have nutritious, medicinal, and even aphrodisiac properties”(Fiegl). It wasn’t until 1828 when a Dutch chemist, Coenraad Johannes van Houten, discovered how to make powdered chocolate from cacao butter that led to our modern idea of chocolate in its solid form (Fiegl). By the late 19^th, early 20^thcentury, well-known chocolate companies such as Mars, Nestle, and Hershey were mass-producing the chocolate confections we know very well today.

Yet it seems as though our knowledge of how chocolate affects our body begins and ends with how our taste buds feel during consumption. There are, however, a number of other ways that chocolate can later influence our mood in addition to the immediate physiological response one feels after taking a bite out of their homemade chocolate cake. One of the ways that chocolate is able to accomplish such a task is through the help of serotonin. Serotonin is a chemical that nerve cells produce to communicate in the brain. Serotonin is known as a “natural mood stabilizer” because it helps reduce depression and regulate anxiety (Health Line). Selective serotonin reuptake inhibitors, which aim to increase serotonin levels in the brain, are the major therapeutic agents used to treat depression, an affective disorder which is the leading cause of disability worldwide” (Jenkins, et al). Chocolate is linked to the neurotransmitter serotonin through a key compound that can be isolated from the chocolate bar itself: Tryptophan. Tryptophan is an amino acid found in small quantities in chocolate and is also the precursor for Serotonin. Clinical studies have used “the tryptophan depletion model to investigate the idea that low serotonin synthesis is associated with depressed mood” (Jenkins, et al). In other words, when tryptophan is low in the diet, there is less serotonin production and thus the individual might feel more depressed or anxious. However, because chocolate contains tryptophan, the resulting increase in serotonin can help explain why one might feel happier, calmer, or less anxious after eating a piece of their chocolate cake (Serotonin).

Chocolate also has the capacity to affect our levels of dopamine, a neurotransmitter that helps control the brain’s reward and pleasure centers (Brookshire). An increase of dopamine in the brain tells the individual that he or she should try and get more of whatever it was that caused that increase. This influences the way we behave in the sense that we keep going back to the thing that makes us feel good, in this case, the chocolate in our chocolate cake. Chocolate contains a key compound called tryamine, which is derived from the amino acid tyrosine. Tyrosine is the amino acid precursor to dopamine (Roizman). With increased tyrosine levels comes increased dopamine levels, which results in the activation of the reward center in the brain. This dopamine pathway can also help to explain the pleasure and joy you might feel after tasting that first bite of the chocolate cake you have just worked hard to bake.

This research goes to show how ingredients used to make a simple chocolate cake can influence how you feel beyond the immediate consumption of your masterpiece. It is critical to understand how an ingredient as straightforward as chocolate influences your body, mind, and mood once it has passed your mouth and entered your digestive tract. We are in a sense manipulating the way we feel by consuming compounds that go on to manipulate the neurochemical signaling that occurs in our brains. Now, the next time you decide to open this cook book and bake this cake, you will not only better understand the steps behind the actual baking that takes place the kitchen, but also how the ingredients used to make this dessert can impact your nerve cells in such a way that can alter your mood. The amount of power we have over our bodies by choosing what we consume is an extraordinary responsibility. However, being aware of this information and understanding how our food can affect how we feel is already half of the battle.

 

References

Brookshire, B. (2017, January 17). Explainer: What is dopamine? Retrieved from https://www.sciencenewsforstudents.org/article/explainer-what-dopamine

Fiegl, A. (2008, March 01). A Brief History of Chocolate. Retrieved from https://www.smithsonianmag.com/arts-culture/a-brief-history-of-chocolate-21860917/

History of Chocolate. (2017, December 14).  Retrieved from https://www.history.com/topics/ancient-americas/history-of-chocolate

Jenkins, T. A., Nguyen, J. C., Polglaze, K. E., & Bertrand, P. P. (2016). Influence of Tryptophan and Serotonin on Mood and Cognition with a Possible Role of the Gut-Brain Axis. Nutrients, 8(1), 56. doi:10.3390/nu8010056

Roizman, T. (2018, June 11). Chocolate & Dopamine. Retrieved from https://healthyeating.sfgate.com/chocolate-dopamine-3660.html

Serotonin: Functions, Side Effects, and More. (n.d.). Retrieved from https://www.healthline.com/health/mental-health/serotonin