Dopamine, Serotonin, and the Gut Microbiome
Dopamine: A More Addictive Reward
Dopamine is a neurotransmitter that gives us pleasure. More significant amounts of dopamine can make many feel euphoric and motivate people to repeat the behavior that triggered the euphoria. It is mostly manufactured in the brain, but surprisingly, almost half is manufactured in the gut!
We receive dopamine from participating in more pleasurable activities, which many times can often be more addictive activities. Humans receive significant amounts of dopamine from drinking alcohol, eating carbohydrates, gambling, having sex, and taking recreational drugs. However, some dopamine is also released from exercise, being in the sunshine, and even smelling freshly baked bread.
Dopamine is vital to survival and regulates motivation. It encourages behaviors that increase the likelihood of survival, such as eating calorie-dense food, which is reinforced by dopamine.
Serotonin: A Stabilizing Reward
Serotonin is a neurotransmitter that is most associated with mood. It is manufactured in the brain and gut and is present throughout the body. However, it is MOST prominent in the GI tract. Serotonin promotes mood stability, making it integral to one's overall sense of well-being. Low serotonin can potentially contribute to anxiety and depression, as this is why many SSRIs help increase serotonin levels in the brain by blocking the reabsorption of serotonin.
Sunlight, meditation, laughing, exercise, omega-3 fatty acids, and probiotics are a few ways to increase serotonin production. Unlike dopamine, many activities that increase serotonin are not considered addictive and are believed to be more stabilizing. Not only does serotonin affect mood, but it also affects numerous other bodily processes such as digestion, wound healing, sex drive, nausea, sleep, and even pain perception.
Dopamine vs. Serotonin: The Main Differences
Although both neurotransmitters bring "happiness," dopamine is seen more as addictive pleasure, whereas serotonin is associated more with contentment. Dopamine is short-term, like eating a piece of cake or winning some money at a slot machine. On the other hand, serotonin is associated with being more long-term, like doing a yoga class or spending a day at the beach.
Dopamine inspires more taking. For example, it inspires cashing in your chips at the casino, whereas serotonin inspires giving, like helping out a friend or volunteering at a soup kitchen. Dopamine inspires taking, however, it is not always a negative. It helps humans survive and reproduce. From an evolutionary perspective, dopamine helps us to do things that keep us alive.
Dopamine typically makes the brain say, "This feels good; I want more," and serotonin typically makes the brain say, "This feels good, and it's enough."
Dopamine and Food
Interestingly enough, dopamine has a role in our food preferences. As mentioned before, the dopamine response can lead to different types of addiction if overstimulated, such as hyper-palatable food and intense cravings for more high-carbohydrate foods for energy to be able to have a quick burst of energy to run fast and make quick decisions.
Humans evolved to seek foods containing substantial quantities of carbohydrates because we needed quick energy bursts to run fast and make quick decisions.
However, if our diet is “carbohydrate dominant” this can affect our dopamine levels to be more “carbohydrate dependent” via the gut-brain axis.
Serotonin and Digestion
Did you know that your gut microbiome houses and manufactures 95% of the body's supply of serotonin? As mentioned previously, this connection is known as the gut-brain axis. The gut-brain axis is a two-way biochemical signaling between the gastrointestinal tract and the nervous system. Part of the nervous system (known as the enteric nervous system) is located in the gut and is embedded in the lining of the GI.
Serotonin affects many functions of your gut, such as how fast food moves through the GI, how much fluid is secreted in the intestines, and how sensitive the intestines are to fullness. Because of the gut-brain axis, many researchers have looked at the links between depression, IBS, and serotonin. One study found that serotonin levels in the colon were ten times higher in IBS participants than in control participants. Thus, they concluded that an imbalance of serotonin may cause symptoms of IBS.
The Bottom Line
Neurotransmitters rule our body physically, mentally, and emotionally. When our gut microbiome is not in optimal shape, it can potentially affect our mood, how we digest, our food cravings, and even how restful our sleep is!
Curious to see how your gut microbiome shapes up? Book a session with Vitamin Kay to dive deeper and take a microbiome test. This test gives a comprehensive and personalized gut report outlining your unique microbiome diversity, phyla balance, presence of beneficial species, and presence of pathogenic species.
