Microbiome and Neurotransmitters

Neurotransmitters, what are they?

Neurotransmitters are chemical messengers used in the brain to activate and suppress brain information pathways. They are responsible for how we feel, think, remember and process information. Key neurotransmitters are necessary for things like memory, happiness, joy, sleep and even movement and libido. When we have imbalances in neurotransmitters we do not feel optimal. It is profound to think that many or even correctly, most of our neurotransmitters are made by our bacteria in the gut! Healthy microbes affect how we think and feel and can help us in many other ways.

Types of Neurotransmitters

The brain and neurons of the body operate using chemical messengers called neurotransmitters. These messengers tell the receiving cell to do different things in the body and brain. When these systems are operating ideally we feel at peace, happy and harmonious. When they are not, we may feel depressed or even irritable and angry. Sleep and alertness are also controlled by these biochemical agents in the brain. The following are some of the neurotransmitters active in the brain.

Serotonin

Serotonin (5-hydroxy-tryptophan) is one of the neurotransmitters responsible for feeling happy, focused and at peace. It is a chemical derived from the amino acid tryptophan. It is also responsible for many diverse actions such as digestion, nausea and vomiting, memory, temperature regulation, hunger and sexual health. It is also involved in wound healing and bone health. Lack of serotonin may lead to depression, anxiety, mania and lack of libido and even osteoporosis. It is important to have well regulated and adequate serotonin to live a healthy life.

Foods for Serotonin

Certain foods can indirectly support serotonin production by providing the necessary building blocks and nutrients. Here are some:

Tryptophan-Rich Foods: Tryptophan is an amino acid precursor to serotonin. Foods like turkey, chicken, eggs, nuts (such as almonds and walnuts), seeds (like pumpkin and sesame seeds), and tofu contain tryptophan.
Complex Carbohydrates: Carbohydrates can aid in the absorption of tryptophan, which is why consuming whole grains like oats, quinoa, barley, and whole wheat products might support serotonin production.
Foods High in Vitamin B6: Vitamin B6 is essential for converting tryptophan into serotonin. Incorporate foods like bananas, spinach, potatoes, chickpeas, and salmon into your diet for their B6 content.
Fruits and Vegetables: Certain fruits and vegetables are rich in nutrients that support overall brain health and might indirectly influence serotonin levels. Examples include pineapple, kiwi, spinach, and other leafy greens.
Probiotic-Rich Foods: While not directly linked to serotonin production, maintaining a healthy gut microbiome through probiotic-rich foods like yogurt, kefir, sauerkraut, and kimchi might indirectly support overall neurotransmitter balance.
Dark Chocolate: Dark chocolate contains compounds that might indirectly enhance mood by supporting serotonin production. However, moderation is key due to its calorie and sugar content.

Remember, the key to supporting serotonin production is a balanced diet that includes a variety of nutrients and adequate levels of tryptophan along with other cofactors necessary for serotonin synthesis. Regular exercise, exposure to sunlight, and managing stress levels also play significant roles in maintaining healthy serotonin levels and overall mental well-being.

Many foods contain precursors to serotonin that may be helpful with levels. Certain herbs may influence production of this important messenger:

Salmon
Eggs
Turkey
Pineapple
Oats
Seeds
nutmeg
Saffron
Ginseng

Certain bacteria in our gut may also produce serotonin and prevent its breakdown. Eating for the microbiome is important to help maintain healthy levels of this important neurotransmitters. These bacteria have been shown to increase healthy serotonin production. see article: Microbiome Health

E. Coli
S. Thermophilus
Lactobacillus Plantarum

Dopamine

Dopamine is derived from the neurotransmitters tyrosine. Dopamine is considered a neurotransmitter involved with reward and motivation. It is also involved in coordination and movement as well as inducing hunger. Parkinson’s disease is associated with a lack of dopamine producing neurons in the brain. Current research even links development of Parkinson’s with lack of beneficial microbes producing butyrate in the gut. Destruction of the substantia nigra in the brain due to dysbiosis and leaking of LPS molecules into the brain has been associated with Parkinson’s as well. Dopamine is produced mostly in the brain but also in the gut by the microbiome.

Foods for Dopamine

Apples
Avocados
Beets
Dark Chocolate
Coffee
Dairy
Eggs
Beans
Turkey
Soy
Leafy Greens

Probiotics and Dopamine

Lactobacillus Rhamnosus
Lactobacillus Plantarum PS 128, DR 7
Prevotella
Bacteriodes
Clostridium

A healthy microbiome is associated with healthier levels of the important neurotransmitter Dopamine. Parkinson’s disease is associated with a lower amount of Dopamine and also now being shown to be associated with a poor microbiome. Species that help regulate Dopamine production and degradation are numerous.

Norepinephrine

Norepinephrine (NE) is important for multiple brain axis functions. It is very involved in the fight or flight response and all of the important aspects of our autonomic nervous system. It is derived from the neurotransmitter Dopamine.
Aspects under control of NEare:
High Levels:

Rapid Heartbeat
Increased sweating
Headaches
Irritability or nervousness

Low Levels:

ADHD
Depression/anxiety
Headaches
Low Blood Sugar
Low Blood Pressure

GABA

GABA, or gamma-aminobutyric acid, is a neurotransmitter in the brain that helps regulate nerve impulses. It’s known for its calming effects and is often taken as a supplement to potentially reduce anxiety, improve mood, and promote relaxation. Some research suggests that certain probiotics might have an impact on GABA levels in the gut, which could indirectly affect brain function and mood.

The gut-brain axis is a bidirectional communication system between the gut and the brain, and the microbiota in the gut can influence various aspects of health, including mental health. Some probiotics, particularly those containing specific strains of bacteria like Lactobacillus and Bifidobacterium, have been investigated for their potential to modulate GABA receptors in the gut, which might affect GABA levels in the brain.

Foods for GABA production:

While there’s no direct way to consume GABA through food because it doesn’t cross the blood-brain barrier easily, there are foods that can potentially support GABA production or promote a calming effect due to their nutrients or compounds.

Fermented foods: kimchi, sauerkraut, kefir, and yogurt contain probiotics, which may support gut health. A healthy gut can indirectly influence neurotransmitter function, including GABA.
Whole Grains: Foods like brown rice, oats, and barley contain high levels of glutamic acid, a precursor to GABA. These can potentially support GABA synthesis in the brain.
Vegetables and Fruits: Certain vegetables and fruits like spinach, broccoli, tomatoes, potatoes, oranges, and berries are rich in vitamins and minerals (such as magnesium, B vitamins, and vitamin C) that can support overall brain health and potentially influence neurotransmitter balance.
Nuts and Seeds: Almonds, walnuts, sunflower seeds, and flaxseeds are good sources of magnesium, which plays a role in GABA regulation.
Tea: Green tea contains theanine, an amino acid that may promote relaxation and has been linked to increasing GABA levels in the brain.
Seafood: Fish like halibut, mackerel, and shrimp are sources of vitamin B6, which is involved in GABA synthesis.
Legumes: Beans, lentils, and peas contain high levels of glutamic acid, contributing to potential GABA support.Herbs:
Certain herbs like chamomile and valerian root have calming properties and may help in relaxation, indirectly affecting GABA function.

While these foods contain nutrients or compounds that could support GABA production or promote relaxation, it’s important to note that the direct impact of diet on GABA levels is not fully established. A balanced diet with a variety of nutrients is crucial for overall brain health and neurotransmitter function. Incorporating these foods as part of a healthy and balanced diet may contribute positively to overall well-being and potentially support GABA-related processes in the body.

Eating for a Healthy Brain and Microbiome

So many of my patients wish to understand what is the healthiest diet to eat. My answer is always- it depends! Each patient may require different recommendations based on what it is they are trying to accomplish and what they might be dealing with medically speaking. Certainly, that is a personalized individual prescription when it comes to foods that will help as each of us are beginning from a different point with different goals in mind. Foods can be used to optimize health in many ways. One way to improve health is by diversifying and improving the microbiome. Healthy bacteria in the gut can help with things like detoxification, inflammation, vitamin production and also even neurotransmitter production. Sort of like the soil of a garden, when we have a healthy microbiome, our health is much easier to maintain.

Eating for the microbiome involves eating plenty of fiber of diversified types. Most of these will come from plants and plant based foods. Things like antibiotics and antimicrobials can dampen the diversity and allow for overgrowth of more inflammatory microbes that do not help with health and lack nutrient production. Certain microbes also help in the production of healthy neurotransmitters which affect how we feel. Microbes are also somewhat responsible for the break down of toxins and even estrogen in our gut. Sometimes, when our microbiome is off, we reabsorb toxins and estrogen which can lead to issues with health.

Conclusions:

While the research on the gut-brain axis and neurotransmitters is exciting, there’s still much to uncover about the specific mechanisms and how interventions targeting the microbiome might be effectively used to support mental health. Nonetheless, it’s becoming increasingly clear that nurturing a healthy gut through diet, lifestyle, and potentially targeted interventions like probiotics could have far-reaching effects on brain function and mental well-being.