Eating a healthy, balanced diet that supports a diverse microbiome is protective against numerous mental health-related conditions such as anxiety and depression. The relatively new field of Nutritional Psychiatry focuses on how diet and gut health can positively or negatively affect mood.
When someone has prescribed an antidepressant such as a selective serotonin reuptake inhibitor (SSRI), the most common side effects are gut-related, such as nausea, diarrhea, or gastrointestinal problems. Anatomical and physiologic two-way communication occurs between the gut and brain via the vagus nerve. Studying this gut-brain axis provides a deeper understanding of the intrinsic connection between diet and disease, including depression and anxiety. These medications are effective at controlling symptoms, but ultimately are unable to solve the problems created by gut dysbiosis and can even make things worse in the long term.
Building and maintaining gut microbe diversity is one of the best strategies to support your mental health through the creation of serotonin, as well as regulate other tasks within the body. Our microbiome is responsible for obtaining nutrients and energy from food, cleansing toxins, fighting viruses, producing hundreds of neurochemicals for regulating essential mental processes such as learning, memory, and mood.
Gut bacteria manufacture between 90-95% of the body's supply of serotonin, which influences both mood and GI activity. Serotonin enables brain cells and other nervous system cells to communicate with each other regulates sleep and waking, aids memory, regulates hunger and digestion, controls bowel movements and function. Serotonin is even important for the process of healing wounds, as it communicates to tiny arteries instructing them to narrow to form blood clots.
SCFAs (short-chain fatty acids) are produced by gut bacteria when we digest fiber. The cells in the colon then use SFAs as their primary energy source, making them essential for maintaining good gut health.
Over time, high levels of stress or poor diet can create intestinal permeability. Tiny particles such as undigested food are then able to move more easily into the bloodstream which can lead to chronic inflammation.
Short-chain fatty acids appear to play a role in mental health. Research studies found that introducing SCFAs to the guts of mice significantly reduced stress and anxiety-related behaviors. They also influence physical gut damage as a result of stress. The researchers found that by introducing SCFAs, they reduced the gut leakiness caused by persistent stress. Although this study was conducted on mice, it indicates that high-fiber diets might propel gut bacteria to produce more SCFAs and increase our gut’s natural defense capabilities against damage caused by stress. In any case, it’s always a good idea to consume more fruit and vegetables for the numerous associated health benefits, so it’s certainly worth a try!