Depression and the Gut-Brain Connection

Depression and the gut-brain connection

Gut health and anxiety and the overall importance of gut health and mental health are gaining increased media and scientific attention. Depression and anxiety disorders are rising worldwide, with those affected experiencing increased disability, lowered quality of life, and significant illness burden.

While genetics, neurotransmitter imbalances, inflammation, and lifestyle play an important role in psychiatric disorders, there is mounting evidence that gut health and mental health, and nutrition, affect when these disorders begin and how they progress.

Exploring the Gut-Brain Connection in Depression

What is the gut-brain axis? Simply put, the gut-brain axis involves two-way communication between the brain and the gut via the vagus nerve.

While it may seem odd that a brain-gut connection exists, an increasing number of studies in recent years confirm its presence and significance in gut health and mental health. Many animal studies from independent research groups corroborate that gut flora imbalance, or an imbalance in intestinal microorganisms, is related to monoamine disruption in depression. This connects mood and gut microbiota.

Furthermore, researchers believe that intestinal barrier defects are linked with chronic low-grade inflammation, which is often found in those with stress-related psychiatric illnesses. Individuals experiencing depression symptoms frequently have higher levels of pro-inflammatory cytokines, C-reactive protein, interferon gamma, and tumor necrosis factor-a. Microbiota in the gut influence the copying or transcription of these cytokines. Gut microbiota imbalance triggers the inflammation pathway.

Depression and Gut Health

How are depression and gut health linked? The gut microbiome consists of bacteria in the trillions from our food and drink. These bacteria influence mood, feelings, and mindset. Recent studies point to a specific bacteria, Eggerthella, consistently found in increasing abundance in depressed individuals’ guts.

When individuals are depressed, their guts may be missing necessary beneficial gut flora. It may be possible to re-energize the gut microbiome by adding those elements. While this may seem challenging, with guidance and support, achieving a health gut and improving depression and gut health is possible.

The Role of Gut Microbiota in Mental Health

Researchers began to explore the connection between depression and gut health in 1910. Yet, a century later, it’s only now that the gut-brain axis is accepted as a critical pathway to prevent and treat depression effectively. But gut health and anxiety are also strongly linked.

Serotonin and the Gut

Numerous studies point to the suggested influence of the gut’s microbiota in regulating serotonin, a neurotransmitter believed to be a depression contributor. Others show how bacteria communicate with the brain. This includes how some bacteria produce butyrate and acetate, short-chain fatty acids, known influencers of brain activity. Other bacteria generate GABA, a chemical whose deficits have been linked with depression.

Stress and Leaky Gut Syndrome

When someone experiences stress, this activates another axis called the hypothalamic-pituitary-adrenal. Then, a torrent of hormones is released that may increase intestinal permeability. Toxins can leak into the bloodstream from the gut. This is called leaky gut syndrome.

Those toxins create an inflammatory response that can travel to the brain through the brain-gut connection. The neuroinflammation caused by stress may trigger anxiety.

Researchers believe that modulating gut microbiota can be effective in fighting or preventing anxiety.

Factors Influencing the Gut-Brain Axis

Many factors are responsible for influencing the gut-brain axis. Notably, researchers believe individuals can reduce risk and improve symptoms of gut health and anxiety, as well as depression and gut health, by eating a diet rich in fresh vegetables, fruits, healthy fats, and whole grains. The brain-gut connection is so strong that imbalances in the gut can trigger mood changes, and eating certain foods can help or disrupt mood.

The Role of the Digestive System in the Brain-Gut Connection

The body’s digestive system breaks down everything we eat. It’s here that the vital nutrients the body needs get absorbed. From there, nutrients move to the brain to play a crucial part in producing neurotransmitters, essential in mood regulation.

Irritating the body’s gastrointestinal system can send signals to the central nervous system, triggering mood changes.

Potential Therapeutic Approaches for Gut-Brain Health in Depression

Anyone experiencing depression or anxiety, among other mental health disorders, wants to find ways to alleviate symptoms, reduce severity and frequency, and potentially overcome the debilitating conditions. Therefore, recent research highlighting therapeutic approaches for improving gut health and mental health in those with depression is promising and worthy of discussion.


For those with major depressive disorder (MDD), psychotherapy can be instrumental in helping to alleviate symptoms and learn to make lifestyle and food choices that may be causing leaky gut syndrome. Other types of psychotherapy may be used to target unhealthy thinking patterns and behaviors. These may include neurofeedback to regulate brainwave activity and transcranial magnetic stimulation (TMS).

Increased Physical Activity

In combination with psychotherapy or other counseling, vigorous physical exercise can be invaluable to help reduce symptoms of depression and improve gut health and anxiety. There is strong evidence supporting aerobic exercise to prevent and reduce depression and other mental health disorders.

  • Aerobic exercise includes walking, dancing, swimming, running, hiking, cross-country skiing, kickboxing, and aerobics classes.
  • Mental health experts recommend engaging in physical activity for at least one hour weekly. Even though the more expertise you get, the better, any exercise will help. This includes movement of any intensity, from low to moderate to strenuous.

Nutritional Psychiatry

It’s a relatively new field, yet nutritional psychiatry holds promise for treating those with anxiety and depression. The impetus in dietary coaching is to provide action steps individuals can take to improve their gut health and anxiety, and depression. For those with psychiatric conditions and disorders, nutritional psychiatry, or precision nutrition, is another practical, low-cost, non-medication way to treat and improve mental health.

Indeed, moderating diet is one of the easiest ways to achieve and maintain a beneficial, healthy gut microbiome. Diet is now regarded as an amenable factor in the protection against psychiatric disorder onset and manifestation by controlling the gut-brain axis.

These include dietary interventions like the recommendations to:

  • Eat a well-balanced and healthy diet, such as the Mediterranean diet, eat more fiber and dietary supplements as necessary, and modify gut microbiota with prebiotics, probiotics, and postbiotics.
  • Avoid foods that trigger inflammation.
  • Consume more fiber to decrease bacteria linked to inflammation and stress, thus potentially reducing depression symptoms.
  • Use nutritional interventions to counter adverse medication effects.

Probiotics for Depression

Several clinical trials have shown evidence of the beneficial effects of using specific types of probiotics in the treatment of anxiety and depression. The class of probiotics involved is called psychomicrobiotics or psychobiotics.

Interestingly, many individuals, especially younger adults who have no prior depression, may prefer initial treatment approaches that do not involve medication, like consuming multi-strain probiotics and careful selection of probiotic strains.

  • A 2015 study found that individuals with depression consuming a multispecies probiotic had significantly reduced incidence of ruminative and aggressive thoughts. The formula included the following specific strains: B lactis, B bifidum, L acidophilus, L casei, L brevis, L lactis, and L salivarius.
  • Another study (2016) found depression improvement scores after an 8-week treatment of consuming three specific probiotics in combination (L acidophilus, Bifidobacterium bifidum, and L casei).

Other Ways to Treat Gut Health and Anxiety and Depression

Try holistic and complementary approaches to treat gut health and anxiety and improve overall gut health and mental health. These can be included in comprehensive treatment plans for depression, anxiety, or other mental health disorders.

According to the National Center for Complementary and Integrative Health (NCCIH), there is evidence that yoga, acupuncture, and music therapy may provide modest improvements or significantly reduce depression symptoms in some individuals.

  • Guided imagery with music, relaxation techniques accompanied by music, and other types of music therapy also show symptom improvements in those with anxiety.
  • These are considered generally safe physical activities with no adverse side effects.
  • Yoga and acupuncture should be used with guidance or administered by qualified practitioners.

Getting Started

If you are experiencing gut health and anxiety or depression and gut health problems, you may wish to consider getting treatment. Our mental health experts at Restore-Mental Health are always available to discuss treatment options and answer all your questions. Contact us anytime for a free consultation.