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.
Gut microbiota has a dual effect on human cognition
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. Despite the methodological limitations in microbiota studies and the potential for overestimation of results, the impact of GM on cognitive processes, particularly decision-making and behavioral preferences, is significant and requires further investigation. These new findings about the effects of GM, particularly on human volition and desires, compel us to reconsider our relationship with at least some types of intestinal microbes.
A new approach called “behavioral microbiomes” is being used to study how microbes influence behavior. This approach considers multiple factors beyond the mere presence of microorganisms. It encompasses the metabolic activity of microbes, interactions among various microbial species, as well as the genetics and environment of the host. The researchers argue that a multidimensional approach is necessary to fully comprehend the intricate relationship between the microbiome and behavior. They suggest that this approach could have significant implications for fields such as neuroscience, psychiatry, and microbiology. The microbiota influences a wide range of human behaviors, including exercise habits, addiction, sleep patterns, and even moral judgments. However, the impact of GM on our appetite and food preferences can have significant effects on our health and may contribute to the development of diseases.
The effect of GM on dietary choices
Some research highlights suggest that our gut microbiome plays a significant role in determining our eating behavior and dietary choices. Scientists have discovered that mice with a less diverse microbiome tend to consume a higher proportion of fat, whereas those with a more diverse microbiome tend to consume more sugar. Some studies have shown that gut microbes may contribute to the preference of obese individuals for unhealthy, high-calorie foods.
An elevated ratio of Firmicutes to Bacteroidetes phyla, which is widely accepted as a normal balance of microbiota, has been linked to an increase in appetite and weight gain. These bacteria are believed to play a crucial role in breaking down complex carbohydrates and producing short-chain fatty acids. The study found that the composition of gut microbes differs between obese and lean individuals. When gut microbes from obese mice were transferred to lean mice, the lean mice developed a preference for high-fat and high-sugar foods. The findings suggest that the gut microbiome may have a significant impact on food preferences and weight gain. Therefore, the individual’s microbiota type should be taken into consideration when designing a diet program to manage eating disorders, obesity, and metabolic diseases .
Microbiome and personalized diet
Personalized nutrition is a novel approach to diet and nutrition that considers an individual’s distinct characteristics, including their genes, lifestyle, and dietary preferences. It utilizes advanced technologies, including genetic testing, blood analysis, and artificial intelligence, to develop personalized nutrition plans that provide to individual needs. This approach aims to optimize health, prevent and manage chronic diseases, enhance athletic performance, and attain specific fitness objectives. Personalized nutrition may involve recommendations for specific foods, meal timing, supplements, and lifestyle modifications that are customized to meet an individual’s unique needs. So far, the most important factors in personalized nutrition was genotype of individuals; however, the microbiome plays a significant role in personalized nutrition, because it can impact how the body processes and absorbs nutrients.
The composition of the microbiome can vary among individuals, which can affect their response to various types of foods and diets. For instance, certain individuals may possess a microbiome that is more adept at metabolizing fiber-rich foods, whereas others may harbor a microbiome that is highly proficient in digesting fats. By analyzing an individual’s microbiome, personalized nutrition plans can be developed that take into account their unique needs and preferences. Additionally, interventions such as probiotics and prebiotics can be used to modify the microbiome and improve its function, potentially resulting in improved overall health and nutritional outcomes .
Recent evidence suggests that genetic testing could enable personalized dietary recommendations based on an individual’s genetic makeup. Certain genes may impact how the body metabolizes certain nutrients, allowing for personalized dietary recommendations. Moreover, analyzing an individual’s microbiome can provide valuable insights into their food digestion and absorption, which can lead to personalized recommendations for achieving optimal gut health. However, further research is needed in this area, and caution should be exercised to avoid oversimplifying the relationship between genetics, microbiome, and nutrition.