Fermented Foods: Nature’s Mental Health Booster

Remarkably, an exciting new study from researchers at the University of Virginia School of Medicine suggests that a common strain of probiotics found in many fermented foods may help reduce anxiety and depression by positively influencing gut bacteria and neurotransmitters. It’s an important finding in terms of understanding the association between fermented foods and mental health and the gut-brain connection.

Here’s what you need to know about probiotics for depression and fermented foods and anxiety, plus a list of probiotic-rich foods to enjoy.

THE GUT-BRAIN CONNECTION

There’s a communication system between your gut and brain called the gut-brain axis or simply the gut-brain connection. Some refer to the gut as the “second brain” because your gut is lined with nearly 170 million neurons.

These neurons are in near constant, bidirectional communication with your brain. The neuronal network of the gut, called the enteric nervous system, manages the functions of the gastrointestinal (GI) tract.

Communicating primarily through the vagus nerve, there are both physical and biochemical messaging between these two areas of the body that can influence the health of the other. What’s more, the microorganisms in your gut appear to play a vital role in this communication.

In an animal study published in December 2024, UCLA researchers demonstrated causal evidence that the gut’s microflora has a direct influence on messaging between the gut and brain through the vagus nerve. It’s another piece of the puzzle in helping scientists understand how probiotics affect the brain.

Considering all the neurons in your GI tract and the direct communication it has with the brain, it makes sense that gut health and mood are closely linked. When your gut health is off, you are more likely to have mental health problems and vice versa.

Related: Long COVID, Inflammation, and the Gut-Brain Axis

This is evident in scientific studies. For example, inflammatory bowel disease is associated with higher rates of anxiety and depression, research has found.

Research points to other connections, too. Although it is not fully understood, increased intestinal permeability (more commonly known as “leaky gut” syndrome) and the inflammation it causes is believed to play a role in a number of mental health conditions – including:

• Depression
• Bipolar disorder
• Anxiety
• ADD/ADHD
• Autism spectrum disorder (ASD)
• Alzheimer’s disease

A HEALTHY MICROBIOME

To help protect and/or boost your mental health, it is necessary to have a basic understanding of how your microbiome works and take steps to keep it healthy. You might be surprised to learn the extent of your gut’s microorganisms.

Collectively, bacteria, yeast, and other microorganisms total about 100 trillion! That is 10 times the total number of cells in the rest of your body. This community of microorganisms is called the microbiome.

The microbiome plays an essential role in the synthesis of neurotransmitters—such as glutamate, GABA, serotonin, and dopamine. Serotonin has a strong influence on mental well-being.

Related: 9 Natural Ways to Balance Dopamine

Maintaining a balanced ratio of healthy bugs to harmful ones in your microbiome is key to gut health. Optimally, in a healthy gut, beneficial bugs make up about 85 percent of the microflora, while harmful bugs are limited to roughly 15 percent.

Of course, there are times when the balance is temporarily disrupted. However, when lifestyle factors lead to chronic disruption, problems arise in your gut—and your mental health can suffer.

The following lifestyle factors can negatively impact the balance of microflora in your microbiome:

• Poor diet
• Too little sleep
• Lack of physical activity
• Added sugars
• Smoking
• Stress
• Medications
• Toxins
• Artificial sweeteners
• Excessive alcohol consumption

In this video, Amen Clinics Integrative Nutritionist Cindy Santa Ana reveals what helps and what hurts the health of your microbiome to enhance overall wellness: