How Fermented Foods Help Promote Better Mental Health

• Fermented foods have the potential to modulate the microbiota-gut-brain axis, offering neuroprotective benefits by influencing gut and brain communication, immune pathways, and nervous system functions
• These foods are an affordable and accessible dietary intervention, providing a practical strategy for enhancing mental health across diverse populations by introducing beneficial microbes and bioactive compound
• Fermented foods contain microbes and molecules with neuroactive potential, which actively influence brain function and mood through the production of microbial metabolites during fermentation
• Long-term consumption of fermented foods is important for achieving mental health benefits, as they help maintain gut and brain barrier integrity, reduce inflammation, and modulate hormone levels like serotonin and GLP-1
• Current studies on fermented foods often lack appropriate controls, leading to challenges in standardizing interventions and accurately measuring their effects on mental health

(Mercola)—Fermented foods stand out as a potent intervention when it comes to influencing your mental health by impacting a symbiotic relationship inside the body, which is called the gut-brain axis. Here, the influx of probiotics influences your mental health, and your current mood subsequently influences your microbiome. While the symbiosis looks simple on paper, it’s a complex communication network, underscoring the importance of eating fermented foods regularly.

Understanding the Link Between Fermented Foods and Mental Health

Fermented foods are rich in beneficial probiotics and metabolites, which influence your gut microbiota composition and diversity. These foods have been well-studied, and researchers eventually discovered that the human body has a communication pathway between your gut and brain — the gut-brain axis.¹

When you eat fermented foods, the probiotics and other bioactive compounds begin to influence the communication between your gut and brain. In particular, a fascinating aspects about them, is their ability to influence mood, and researchers attempted to quantify their benefits in one study.

Fermented Foods — A Practical Path to Attaining Mental Wellness

The paper, published in Neuroscience & Biobehavioral Reviews, found that fermented foods offer an affordable dietary intervention strategy to enhance your mental health by targeting the gut-brain axis.² But before diving in further, the researchers established the definition of the gut-brain axis in their research:

“The microbiota-gut-brain axis facilitates a constant bidirectional relay of information from the intestine via the enteric nervous system (ENS) and from the intestinal milieu consisting of microbial communities, microbial metabolites, gut associated lymphoid tissue (GALT), peripheral immune cells and cytokines to the brain and vice versa via the sympathetic/parasympathetic nervous system, neurotransmitters and the circulatory immune system.”

Using this definition as the foundation, the researchers noted that incorporating fermented foods into your diet introduces a diverse array of beneficial microorganisms, resulting in a balanced gut microbiome. Moreover, this approach is convenient and cost-effective compared to taking a supplement, especially for families coming from different socioeconomic backgrounds around the world, as it offers them a way to stay healthy without resorting to adding another layer of expense.³

The neuroactivity of fermented foods is achieved through the introduction of probiotics into the digestive tract during consumption, which interact with the gut-brain axis. Enhanced microbiota diversity ensures a more resilient and efficient gut environment, which directly impacts brain health and function.⁴

Research also shows probiotics modulate immune and nervous system pathways, as well as impact the hypothalamic-pituitary-adrenal (HPA) axis, which is crucial for stress regulation. Probiotics also influence hormone levels, such as the gut hormones GLP-1, which plays important roles in glucose homeostasis and satiety.⁵

Going back to the gut-brain axis, fermented foods influence pathways that relay information from the gut to the brain by altering neurotransmitters, neuroactive substances and neuromodulators. These compounds play vital roles in regulating mood, stress response and overall cognitive function. In turn, this helps maintain the human body a balanced state of mental health, reducing the risk of disorders such as anxiety and depression.⁶

Moreover, fermented foods contain metabolites that reduce the permeability of both the intestinal barrier and the blood-brain barrier.⁷ A strong barrier prevents harmful substances from entering the bloodstream and reaching the brain, thereby protecting it from inflammation. This is a key factor in preventing neuroinflammation and promoting cognitive resilience.⁸

Other Effects of Fermented Food on Human Physiology

Fermented foods exert immunomodulatory effects by influencing the levels of circulating cytokines and other immune markers. These benefits help reduce systemic inflammation, which is often linked to various mental health issues. By supporting the immune system, fermented foods create a healthier body and mind.⁹

The study also points out that probiotics influence the production of hormones such as serotonin, neuropeptide-Y, GLP-1, ghrelin, peptide YY, motilin and somatostatin, which play significant roles in regulating appetite, mood and energy. This promotes metabolic health, which is closely linked to mental health.

That’s because a well-regulated metabolic system aids in maintaining stable energy levels and mood, thus preventing the onset of mood swings and symptoms of depression. Certain probiotic strains also lower stress levels, which is another benefit that promotes better mood and overall health.¹⁰

The study underscores that fermented foods influence neurotransmitter levels, including serotonin, which is a key player in mood regulation.¹¹ The slight boost in serotonin levels help enhance feelings of well-being and happiness, reducing the prevalence of mood disorders.

However, note that serotonin levels shouldn’t be always elevated. As noted in my article “Media Twists Findings of Study Linking High Serotonin to Dementia,” elevated serotonin levels will contribute to health issues such as:

• Fibrosis, including cardiac and pulmonary fibrosis
• Impaired thyroid function
• Reduced metabolism due to excessive glycolysis and high lactic acid production
• Reductive and then secondary oxidative stress
• Bizarre, recurring nightmares and post-traumatic stress disorder (PTSD)

Strategies to Nourishing Your Gut Microbiome

Are you eating enough fermented foods? If you’ve been feeling down lately, adding them into your diet will give your mood a nice boost. This strategy subsequently affects the microbiota-gut-brain axis that results in better overall mental health. To help you achieve this goal, here are some practical steps:

Additional Strategies to Boost Your Mood

While fermented foods are certainly important, there are other strategies available to help boost your mood. One of my top recommendations is getting regular exercise. Not only is it free, it’s also easy to incorporate into your daily routine.

In a study¹³ published in the British Journal of Medicine, researchers noted that exercise is better than antidepressants when it comes to improving mental health. In fact, according to their calculations, it’s 1.5 times more effective. As noted by lead author Ben Singh, Ph.D.:¹⁴

“Physical activity is known to help improve mental health. Yet despite the evidence, it has not been widely adopted as a first-choice treatment … Higher-intensity exercise had greater improvements for depression and anxiety, while longer durations had smaller effects when compared to short and mid-duration bursts.

We also found that all types of physical activity and exercise were beneficial, including aerobic exercise such as walking, resistance training, Pilates, and yoga. Importantly, the research shows that it doesn’t take much for exercise to make a positive change to your mental health.”

Aside from exercise, eating a healthier diet (in addition to fermented foods) will help boost your mood. I recommend adding more vitamin B-rich foods into your diet, as this nutrient plays a role in cognitive function. For example, a B1 deficiency causes irritability and emotional disturbance. On the other hand, a B3 deficiency has been linked to anxiety, aggression and depression.¹⁵

Lastly, I recommend you try the Emotional Freedom Techniques (EFT). It’s a form of psychological acupressure that takes inspiration from the concept of energy meridians used in acupuncture. In EFT, you’re tapping certain meridians while voicing out positive affirmations to help uplift your mood. That said, people experiencing the symptoms of depression will benefit from EFT. In the video below, EFT practitioner Julie Schiffman shows you how.

• ^{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11} Neuroscience & Biobehavioral Reviews, March 2024, Volume 158
• ¹² Int J Mol Sci. 2022 Aug 24;23(17):9588, Introduction
• ¹³ British Journal of Sports Medicine 2023;57:1203-1209, Abstract
• ¹⁴ University of South Australia, February 24, 2023
• ¹⁵ Nutrients. 2016 Jan 28;8(2):68, Table 1