Similar to our hunter-gatherer ancestors, we have an evolutionary preference for high-calorie foods. Our ancestors developed a genetic program to store as much energy and valuable nutrients as possible for periods when food was scarce. Therefore, we have inherited genes that make it challenging for us to resist delicious food, which can lead to obesity, diabetes, cardiovascular diseases, and even cancer, despite the fact that we no longer experience food shortages like in the past.

However, in order to manifest pathological phenotypes, these genes must interact with environmental influences. It seems that the gut microbiome (GM) plays a critical role in regulating these paleo-genes. The human gut accommodates tens of trillions of microorganisms, including bacteria, viruses, fungi, and other microorganisms collectively referred to as the GM. The GM has been present in the intestines of our human-like ancestors and has evolved alongside them, eventually reaching modern homo sapiens. So far, it has been believed that GM has a reciprocal symbiotic relationship with humans, resulting in beneficial effects for both parties. However, it is important to note that our relationship with GM may not always be a permanent, reciprocal, symbiotic one. At times, this relationship may become harmful to us.

Recent studies have shown that GM can have both positive and negative impacts on our mood, decision-making, and behaviors. This is often referred to as the "gut-brain axis." Several studies have shown that imbalances in the microbiota, known as dysbiosis, may lead to various mental and cognitive alterations, including anxiety, depression, and even autism. On the other hand, our moods have an effect on the diversity of microbiota.........

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