Our bodies are constantly influenced by external factors that interfere with the bodily balance state, called homeostasis. To keep this balance, we have many systems in our body that aim to keep or restore this state when an external factor causes perturbations. Probiotics and a healthy lifestyle are one way to maintain a healthy balance of our intestinal microbes.
A healthy microbiota is characterized by resistance and resilience. This is defined as the ability to resist an external perturbation and to return to the pre-perturbation state after a change occurs, respectively . Gut microbiota are excellent at adapting to new environments , but in the case of maintaining homeostasis this can be a double-edged sword: if an external factor is stronger than the stability of the gut ecosystem, this can interfere with its resistance and resilience capacities . This in turn can prevent the microbial community to return to the homeostatic state, resulting in a state of permanent dysbiosis, which is the opposite of homeostasis [4,5]. Such dysbiosis can occur either in terms of bacteria composition or in their functionality [6,7]. At this point where dysbiosis predominates over balanced states, the consequences can be detrimental to an individual’s health .
So what are these external factors that can shake up our intestinal ecosystems? Certain factors in our lifestyle can influence our microbiota and affect the homeostatic processes of the human body . This promotes the development of chronic oxidative and inflammatory processes overtime, and makes us more vulnerable for diseases .
One of the most important factors of our lifestyle is diet. In particular, long-term dietary habits, which include not only the specific composition of nutrients, but also meal times and food behaviors, account for deeper and chronic changes in the gut microbiota than short dietary interventions . In addition, there are several nutrients and bioactive compounds that can affect the gut microbiota (both in beneficial and in harmful ways) and have been frequently investigated, such as probiotics (including yogurts), prebiotics (fibers and polyphenols), alcoholic beverages, sweeteners, and fats.
More specifically, probiotics play a relevant role in our diet and are defined as “live microorganisms, which when administered in adequate amounts, confer a health benefit on the host” . It is known that whereas a high bacterial diversity has been associated with a better metabolic profile and a good health status, a loss in bacterial diversity is a typical feature of certain metabolic disorders, such as obesity .
However, in addition to factors such as diet, intestinal dysbiosis is also influenced by changing eating habits that involve the consumption of processed foods that contain artificial ingredients, such as sweeteners; and worsening other lifestyle habits, such as smoking, drug use, and sleep, can together contribute to poor health as well as the development of chronic diseases .
Thus, although the balance of intestinal microbes appears to be critical to achieving long-term health preservation due to their role in homeostatic processes, it is important to remember that in addition to a good diet, it is necessary to maintain good lifestyle habits for achieving health preservation in the long term.
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