Currently, a huge body of work confirms that gastrointestinal inflammation may play a critical role in the development of depression.

Thus, in some cases, beneficial bacteria (probiotics that reseed the intestinal flora) can be more effective than any other type of treatment.

A Hungarian scientific study published in 2011 relates the following observations: depression very often occurs alongside inflammations and autoimmune diseases that affect the gastrointestinal sphere. But it is also the case when there is a cardiovascular disease, a neurodegenerative disease, a type 2 diabetes or a cancer. All these health problems have in common a chronic inflammatory terrain. This factor contributes significantly to the development of a depressive terrain.

Thus, the depression presented for decades by scientists as a brain disorder or an imbalance of certain neurotransmitters would be a neuropsychiatric manifestation of a chronic inflammatory syndrome.

This postulate is confirmed by numerous clinical studies. They demonstrated that treating gastrointestinal inflammation with probiotics, vitamin B, and vitamin D greatly reduced symptoms and depression. The conclusion of this research suggests that the primary cause of brain and behavioral disorders is dysfunction of the gut-brain axis.

For some years now, moreover, many books and therapists have been talking about the fact that the gut would literally be the body's second brain. This is totally plausible since the gut and the brain are built from the same embryonic tissue and both are controlled by similar neurotransmitters.

This argument is supported by the fact that gut bacteria produce as much, if not more, serotonin than the brain itself.

The lesson here is that we need to take good care of our gut, as it is a fundamental part of the equation for our mental state and overall manifest health. So if you eat a lot of processed foods, if you eat a lot of sweets or sodas, or if you eat a lot of meat, your intestinal flora is inevitably damaged and decimated. When they are insufficient, commensal bacteria are replaced by pathogenic germs, yeasts and fungi that promote inflammation and disrupt brain health.