Harmonizing gut microbiota dysbiosis: Unveiling the influence of diet and lifestyle interventions

Abstract

The gut microbiota, comprising trillions of microorganisms inhabiting the gastrointestinal tract, is essential to human health and disease. Recent research has illuminated the interactions between many components of human physiology and the gut microbiota, including immune function, metabolism, and neurological health. Central to maintaining this symbiotic relationship is the concept of dysbiosis – an imbalance in the makeup and roles of the gut microbiota. Dysbiosis of the gut microbiota has emerged as a significant factor in the pathogenesis of numerous health conditions, spanning from gastrointestinal disorders like inflammatory bowel disease and irritable bowel syndrome to systemic diseases such as obesity, metabolic syndrome, and even neurological disorders like depression and anxiety. While dysbiosis can result from a myriad of factors including antibiotic use, stress, and genetic predispositions, emerging evidence suggests that diet and lifestyle choices exert profound influences regarding the make-up and capabilities of the gut microbiota. In this review, We explore the complex interactions among lifestyle, nutrition, and gut microbial dysbiosis. In particular, we investigate how the gut microbiota can be modified and dysbiosis can be mitigated by dietary patterns, food composition, prebiotics, probiotics, and lifestyle factors including exercise, stress reduction, and good sleep hygiene. Restoring microbial balance and enhancing general health and well-being can be achieved through preventive and therapeutic measures that can be made more effective by understanding how dietary and lifestyle changes might affect the gut microbiota. Through this exploration, we aim to elucidate the possibility of using lifestyle and dietary modifications as tools for managing gut microbial dysbiosis.

1. Introduction

1.1. Gut microbiota

The gastrointestinal tract houses a complex ecosystem of microorganisms collectively known as the gut microbiota, which plays a pivotal role in human health [1]. Comprising a diverse array of bacteria, viruses, fungi, archaea, and protozoa, the gut microbiota exerts a profound influence on numerous physiological processes [2]. Among these microorganisms, bacteria represent the most prevalent and diverse group within the gut microbiota, with thousands of distinct species [1]. While Firmicutes and Bacteroidetes are the dominant phyla, Actinobacteria, Proteobacteria, and Verrucomicrobia also constitute sizable populations [3]. These microbes play vital roles in various aspects of human health, including immunity, digestion, metabolism, and mental well-being (see Fig. 1). Several key functions underscore the importance of the gut microbiota in human health. First, it contributes significantly to nutrient absorption and digestion by breaking down complex proteins, lipids, and carbohydrates that human enzymes alone cannot fully digest [4]. Additionally, gut microbes produce digestive enzymes that assist in the breakdown of dietary fibers, thereby releasing nutrients for absorption by the body. These processes highlight the intricate symbiotic relationship between the gut microbiota and human physiology, emphasizing its indispensable role in maintaining overall health and well-being.

Fig. 1.

Impact of healthy and unhealthy diet and lifestyle on the gut bacteria: Balanced diet with complex carbohydrates, regular exercises and physical activity promote probiotic microbiota that produce short chain fatty acids; acetate, propionate, butyrate on the contrary unhealthy fatty diet consisting of oligosaccharides, pollution, sedentary lifestyle, stress, alcoholism and smoking promote growth of pathogenic microbiota leading to production of toxic modified SCFAs, LPS and other microbial toxins. These metabolites tend to impact; the muscles, brain, liver and adipose tissue; influencing the metabolism positively/negatively based on the microbial flora producing it.

In adults, the gut microbiota typically comprises various genera of bacteria, notably including Bifidobacterium, Lactobacillus, Bacteroides, Clostridium, Escherichia, Streptococcus, and Ruminococcus [5]. Notably, a substantial proportion, approximately 60 %, of these bacteria are from Firmicutes or Bacteroidetes phyla. Additionally, methane-producing microbes, classified as Archaea rather than bacteria, are present in about half of individuals. While individuals may harbour hundreds of species of gut microbes, recent research, such as that from initiatives like The Human Microbiome Project, suggests the presence of thousands of distinct microbial species collectively inhabiting the human gut, underscoring significant variation in population composition among individuals. Despite this taxonomic diversity, many microbial genes responsible for fundamental metabolic functions exhibit similar abundance levels across individuals [6].

Accumulating evidence suggests that imbalances in gut microbiota can contribute to diseases such as inflammatory bowel disease, leading to increased recognition of the microbiota's role in maintaining the health and driving significant research and business ventures in this arena. Gut microbes secrete a variety of bioactive compounds with varying effects on health, ranging from beneficial vitamins to potentially harmful toxins. Host immune defenses, including the mucous barrier, play a vital role in preventing tissue damage caused by potentially harmful bacteria. By competing for resources and colonization sites, the maintenance of a varied and robust population of beneficial gut microbes helps suppress dangerous bacteria. The composition of each person's gut microbiota varies depending on several factors, including genetics, diet, age, location, and lifestyle [7]. Despite this variation, several core microbial species are generally present in all individuals and support fundamental gut processes. The maintenance of healthy population of gut microbiota is largely dependent on dietary interventions, especially the consumption of a variety of fibers. Furthermore, strategies such as probiotics may aid in promoting health [7]. This review aims to elucidate topics concerning diet, lifestyle, gut microbiota, and health while also highlighting prospects and gaps in knowledge in this field [4].

1.2. Short-chain fatty acids (SCFA)

Short-chain fatty acids (SCFAs) serve as pivotal mediators of cellular function across various local, intermediary, and peripheral tissues, raising intriguing questions about their role as the fundamental molecular link connecting diet habits, lifestyle, the microbiome, and health. With renewed interest in SCFAs and advancements in molecular biology tools, emerging evidence underscores the crucial role of SCFAs in the intricate interplay between diet, the gut microbiome, and host metabolism [8]. While the microbiome primarily functions as a system for substrate degradation, SCFAs act as active signaling molecules facilitating microbiome-host communication. Predominantly produced within the gut lumen, SCFAs exhibit selective uptake mechanisms, with acetate absorbed in peripheral tissues, propionate at the liver, and butyrate at the epithelium. Hepatic portal system rapidly delivers SCFAs and other metabolites to the liver, yet the precise function of molecular signaling in various liver cell types remains incompletely characterized. SCFAs have the potential to influence resident macrophages and hepatocytes, albeit with potential functional specificity for each SCFA [9]. Additionally, incretin hormones may exert effects on peripheral tissues and hepatocytes, establishing a dual signaling system that collectively contributes to maintaining liver health by regulating hepatic metabolism, inflammation, and controlling the flux of free fatty acids derived from adipose tissue [8]. Peripheral effects of SCFAs demonstrate tissue-specific characteristics, modulating insulin levels in the pancreas, regulating the flux of free fatty acids from adipocytes, influencing appetite centres of the brain, and serving as a fuel source for muscle tissue [8].

SCFAs result from the saccharolytic fermentation of carbohydrates that are unable to be absorbed and digested in small intestine. The pathways producing SCFAs, primarily butyrate, formate, acetate, and propionate, have been well-established and recently elucidated. Additionally, lactate, produced by the fermentation of certain non-digestible carbohydrates (NDCs), serves as a noteworthy organic acid. Protein-derived branched-chain amino acids ferment and produce minor amounts of branched-chain fatty acids. Despite the association of formate with methanogenesis and its elevation in inflammatory conditions, its function in the gut remains largely unknown. Nonetheless, a variety of cross-feeding organisms can further metabolize lactate into acetate, propionate, and butyrate [8]. However, despite the growing evidence on the benefits of SCFA, some studies reveal variability in SCFA production among individuals, even on similar diets, indicating the need for personalized microbiome interventions.

1.2.1. Dysbiosis

Dysbiosis of the gut refers to an imbalance or disruption in the composition and function of gut microbiota, often characterized by a reduction in beneficial microbes and an increase in harmful or pathogenic ones [10,11]. This imbalance can manifest in various gastrointestinal symptoms and is linked to a spectrum of health conditions, such as inflammatory bowel disease, irritable bowel syndrome, obesity, metabolic disorders, and autoimmune diseases. Factors like diet, antibiotic usage, stress, and certain medical conditions can contribute to dysbiosis [12]. In this review, we delve into the intricate interplay between diet, lifestyle, and gut microbiota dysbiosis. Specifically, we explore how dietary patterns, nutrient composition, prebiotics, probiotics, and lifestyle factors such as physical activity, stress management, and sleep hygiene can modulate the gut microbiota and alleviate dysbiosis. Understanding the influence of diet and lifestyle interventions affecting gut microbiota presents promising opportunities for preventive and therapeutic strategies aimed at restoring microbial balance and enhancing overall health and well-being. Through this exploration, we aim to illuminate the potential of leveraging diet and lifestyle modifications as effective tools in the management and mitigation of gut microbial dysbiosis.

2. Factors influencing gut microbiota

2.1. Diet

Diet plays a crucial role in sculpting composition of gut microbiota. Diet rich in fruits, vegetables, whole grains, nuts, seeds, and olive oil is associated with a more diverse and beneficial gut microbiota profile. This dietary pattern promotes higher prosperity of favourable bacteria such as Bifidobacterium and Lactobacillus. In contrast, the Western diet, characterized by high consumption of processed foods, red meat, saturated fats, and refined sugars, is linked to reduced gut microbial diversity and alterations in microbial composition. Specifically, it leads to reductions in favourable bacteria and increases in potentially harmful species [22]. The gut microbiome is profoundly influenced by dietary components that remain undigested and undergo metabolization, shaping its structure, composition, and function. Maintaining intestinal homeostasis relies on intricate interactions between the gut microbiome, mucosal immune system, and gut epithelium [13]. Among the most significant factors affecting gut microbiota composition is diet quality. A diet rich in fiber, fruits, vegetables, and whole grains fosters the growth of essential bacteria, while a diet high in processed foods, sugars, and fats can disrupt microbial balance [13].

Dietary fiber acts as a prebiotic, nurturing beneficial gut bacteria. Fiber-rich foods like fruits, vegetables, legumes, and whole grains are pivotal for cultivating a diverse and healthy gut microbiota. While humans lack the enzymes to digest fibers, they serve as substrates for gut bacteria to ferment into short-chain fatty acids (SCFAs), including acetate, propionate, and butyrate, which confer anti-inflammatory and metabolic benefits. Butyrate, especially, serves as an optimal energy source for the colonocytes and helps preserve gut barrier integrity [14]. High-fiber diets are linked with greater gut microbiota diversity and increased abundance of fiber-degrading bacteria [15]. Various types of dietary fibers play distinct functional roles, as illustrated in Table 1.

Table 1.

Types of Dietary fibers and their function [21].

Dietary Fibers
Types	Soluble	Insoluble
Constituents	Inulin, Pectin, Beta-glucans	Waxes, Chitins, Cellulose, Hemicellulose
Sources	Oats, Beans, Fruits, Vegetables, Prunes, Barley	Barley, Brown rice, Nuts & Seeds, Dried beans
Functional Role	Reduces; Postprandial glucose reponse, Total & LDL cholestrol, Gastric emptying	Reduces; Risk of Diabetes Type 2. Increases; Insulin sensitivity, Gut transit time

Polyphenols found in foods such as berries, nuts, tea, and dark chocolate encourage the growth of favourable gut bacteria like Bifidobacteria and Lactobacilli while inhibiting harmful bacteria. With antioxidant and anti-inflammatory properties, polyphenols contribute to gut health by reducing inflammation and oxidative stress [16]. Probiotics, live microorganisms ingested in suitable amounts, confer health benefits to the host. Foods like yogurt, kefir, kimchi, sauerkraut, and miso contain probiotic bacteria that aid in replenishing and diversifying the gut microbiota. Additionally, fermented foods undergo a fermentation process enhancing nutrient and bioactive compound availability, further promoting gut health [17]. Consumption of animal-derived foods, particularly meat and dairy, can negatively impact gut microbiota composition if not balanced with dietary fibers [18]. Dietary fats, especially saturated and trans fats, influence composition of gut microbiota, with high-fat diets, especially those rich in animal fats, linked to reduced gut microbiota variety and altered microbial metabolism [17]. Conversely, diets rich in healthy fats found in fish, nuts, seeds, and olive oil may have more favourable effects on gut microbiota composition.

High intake of refined sugars and artificial sweeteners can disrupt composition and function of the gut microbiota, potentially leading to dysbiosis and increased intestinal permeability, contributing to metabolic dysfunction and inflammation [19]. Processed foods often lack fiber and other essential nutrients for a healthy gut microbiome [20]. Some studies suggest that artificial sweeteners like saccharin, aspartame, and sucralose may modify gut microbiota composition and metabolism, though the long-term effects remain unclear [19]. Table 2 provides an integrated overview of these interventions, detailing microbial alterations and associated health outcomes, offering a critical tool for clinicians and researchers. By comprehending the intricate interactions between diet and gut microbiota, individuals can make informed dietary choices that foster a diverse and balanced microbial community in the gut, thereby supporting overall well-being and health [23].

Table 2.

Summary of dietary and lifestyle interventions on gut microbiota and disease implications [ADDED as per reviewer 2].

Intervention	Example	Effect on Gut microbiota
Dietary Fiber	Whole grains, legumes, fruits, vegetables	Increases diversity and promotes short-chain fatty acid (SCFA) producers (e.g. Bifidobacteria, Lactobacilli) SCFAs like butyrate support gut barrier and immune function
Prebiotics	Inulin, fructooligosaccharides (FOS), GOS	Selectively stimulates beneficial bacteria like Bifidobacteria and Lactobacilli. Often added in functional foods
Probiotics	Lactobacillus, Bifidobacterium species (from fermented foods or supplements)	Can temporarily increase beneficial strains and modulate immune response. Effects may be strain-specific and temporary
Fermented Foods	Yogurt, kefir, sauerkraut, kimchi	Introduces live microbes and enhances microbial diversity. May support resilience of microbiota
Polyphenols	Berries, green tea, dark chocolate	Promotes growth of beneficial bacteria, e.g. Akkermansia, Bifidobacterium. Acts as substrates for microbial metabolism
Animal-Based Diets	High red meat, low fiber	Increases Bacteroides, decreases SCFA production, may raise pro-inflammatory species. Linked to lower diversity and dysbiosis if long-term
Plant-Based Diets/vegetarian	Fruits and Vegetables	Increases Prevotella and SCFA-producing bacteria. Associated with healthier microbial profiles
Exercise	Moderate exercise	improves microbial diversity, promotes SCFA producers. Sedentary lifestyle associated with lower diversity
Sleep Quality	7–9 h/night, regular schedule	Poor sleep linked to dysbiosis and gut-brain axis disruption.
Stress	Stress	Stress-induced dysbiosis; Chronic stress negatively alters microbiota
Antibiotics	Broad-spectrum antibiotics	Major reduction in microbial diversity; risk of Clostridioides difficile overgrowth.
Artificial Sweeteners	Aspartame, sucralose, saccharin	May disrupt microbiota composition, reduce SCFA levels and linked to glucose intolerance in some studies
Alcohol	Alcohol	Chronic high intake. Reduces microbial diversity, increases gut permeability
Smoking	Cigarettes, vaping	Associated with dysbiosis, increased Proteobacteria

2.2. Antibiotics

Antibiotics, while designed to eliminate harmful bacteria, can inadvertently disrupt the delicate balance of gut microbiota by indiscriminately targeting both beneficial and harmful bacterial species. This disruption often results in a reduction in microbial diversity, potentially leading to various health concerns [24]. Impact of antibiotics on gut microbiota is a complex and multifaceted phenomenon that has attracted considerable attention from researchers in recent years [10]. Broad-spectrum antibiotics act on a wide array of bacteria, encompassing both beneficial and harmful strains, whereas narrow-spectrum antibiotics exhibit greater selectivity, targeting specific types of bacteria. The consequences for gut microbiota composition vary depending on the spectrum of antibiotics employed [25].

Antibiotics can deeply impact the composition and variety of the gut microbiota by selectively targeting certain bacterial species. While they effectively combat pathogenic bacteria, antibiotics can also disrupt beneficial or commensal bacteria crucial for maintaining gut health [10]. For instance, antibiotics may diminish the abundance of bacteria involved in producing SCFAs, vital for gut barrier function and immune regulation. This disruption often leads to reduced microbial diversity, that is associated with various health issues. Prolonged or repeated antibiotic use can result in dysbiosis, an imbalance in gut microbial composition [25]. Dysbiosis induced by antibiotics creates an environment more susceptible to colonization by opportunistic pathogens and has been linked to gastrointestinal disorders such as inflammatory bowel disease (IBD), irritable bowel syndrome (IBS), and Clostridium difficile infection (CDI).

While gut microbiota is able to partially recover following antibiotic treatment, complete restoration of its composition and function may take weeks to months [10,26]. In some instances, the impact of antibiotics on the gut microbiota can be long-lasting or permanent, particularly with repeated or excessive antibiotic use, with systemic effects on host health extending beyond the gastrointestinal tract [27]. Recent research suggests that alterations in the gut microbiota may contribute to the development of conditions such as obesity, metabolic syndrome, autoimmune diseases, and mental health disorders. The impact of antibiotics on the gut microbiota results from a complex interplay between the antibiotic spectrum, duration and frequency of use, and the resilience of gut microbiota. Understanding these dynamics is crucial for mitigating the adverse consequences of antibiotics on gut health and overall well-being [28].

2.3. Lifestyle choices

Various lifestyle factors, including smoking, alcohol consumption, and physical activity, can significantly influence the composition of gut microbiota. For instance, smoking has been associated with changes in gut microbial diversity, whereas consistent physical activity tends to foster a more diverse and beneficial gut microbiota. The influence of lifestyle on gut microbiota composition is complex and multifaceted, with dietary habits, levels of physical activity, stress levels, quality of sleep, and circadian rhythms all exerting pivotal roles in shaping the microbial communities in the gastrointestinal tract. Here's a detailed examination of how different lifestyle choices influence gut microbiota composition.

Physical Activity and Exercise: Physical activity and exercise exert profound effects on composition and function of gut microbiota. Regular physical activity is linked to enhanced gut microbiota diversity and a more resilient microbial community structure. The variations in gut microbiota induced by exercise may stem from changes in gut motility, blood circulation, and metabolic processes [29]. Physical activity fosters the proliferation of beneficial bacteria and augments microbial diversity, potentially contributing to the metabolic and anti-inflammatory benefits associated with exercise. Conversely, sedentary behavior correlates with diminished gut microbiota variations and alterations akin to those observed in individuals with a Western diet and metabolic disorders [29]. Exercise-induced modifications in gut microbiota include increases in beneficial bacterial taxa such as Firmicutes and Bacteroidetes, which are linked to improved metabolic health and bolstered immune function [29]. Furthermore, physical activity enhances gut barrier integrity by reducing gut permeability and upregulating expression of tight junction proteins. This fortification of the gut barrier mitigates the translocation of bacteria and toxins from the gut into the bloodstream, thereby diminishing the risk of inflammation and metabolic disorders [29].

Stress: Psychological stress can impact gut microbiota composition through the brain-gut axis, a bidirectional communication pathway between central nervous system and gastrointestinal tract [30]. Stress-induced alterations in gut microbiota might be mediated by changes in gut motility, immune function, and release of stress hormones such as cortisol [31].

Sleep Quality: Poor sleep quality and disrupted circadian rhythms have been associated with alterations in gut microbiota's composition and increased gut permeability. Disruptions in circadian rhythms can affect the timing of gut microbial activity, leading to dysbiosis and metabolic disturbances [32].

Circadian Rhythms: The gut microbiota displays diurnal fluctuations in composition and function, regulated by the host's circadian rhythms and feeding-fasting patterns. Disruptions in circadian rhythms, such as irregular meal schedules or shift work, can disturb the timing of microbial activities, potentially leading to dysbiosis and metabolic disorders [33].

Smoking: Smoking is linked to significant alterations in gut microbiota's composition, characterized by reductions in beneficial bacteria like Bifidobacterium and elevations in potentially harmful bacteria such as Firmicutes. These changes have been involved in promoting inflammation and heightening susceptibility to various diseases. Smoking also correlates with increased gut permeability, resulting in a condition colloquially termed "leaky gut" [34]. This compromised gut barrier allows harmful substances to breach into the bloodstream, inciting inflammatory responses and potentially contributing to the onset of gastrointestinal disorders. Additionally, smoking can influence the production of microbial metabolites in the gut, including short-chain fatty acids (SCFAs) [35].

Alcohol consumption: Chronic alcohol consumption has been associated with to disturbances in the balance of gut microbiota, resulting in changes in microbial composition and reduced diversity. This imbalance often involves an increase in pathogenic bacterial species, which could contribute to inflammation and dysfunction in gastrointestinal tract [36]. Alcohol consumption disrupts the integrity of the gut barrier, leading to heightened permeability and the leakage of bacterial toxins into the bloodstream. Consequently, this can trigger immune responses and inflammation, thereby fostering the development of conditions such as alcoholic liver disease and other gastrointestinal disorders [36]. Moreover, alcohol metabolism in the gut generates harmful byproducts like acetaldehyde, which can inflict damage on the intestinal lining and disrupt microbial metabolism. These alterations have the potential to interfere with the production of short-chain fatty acids (SCFAs) and other microbial metabolites, exacerbating gut dysbiosis and inflammatory responses [37].

Age: The gut microbiota undergoes dynamic changes throughout an individual's life, with notable shifts occurring during infancy, childhood, and old age. Factors like the mode of birth (vaginal delivery vs. cesarean section), breastfeeding, and the introduction of solid foods play pivotal roles in shaping the early development of gut microbiota [38]. Age is a significant factor to determine of gut microbiota composition and function, influenced by diverse factors including diet, lifestyle, medications, and physiological changes associated with aging. These factors collectively contribute to the continuous evolution of the gut microbiota throughout the lifespan. For a comprehensive understanding of how age impacts the gut microbiota, further exploration is warranted [39].

2.4. Disease and health conditions

Several medical conditions, including diabetes, obesity, irritable bowel syndrome (IBS), and inflammatory bowel disease (IBD), are associated with changes in composition of the gut microbiota [40]. These alterations can disrupt the delicate balance between beneficial and harmful bacteria, potentially worsening symptoms [12]. IBD, comprising ulcerative colitis and Crohn's disease, is characterized by persistent inflammation in gastrointestinal tract. Dysbiosis in individuals with IBD often involves reduced microbial variations and shifts in specific bacterial populations, such as decreases in Firmicutes and increases in Proteobacteria. This dysbiosis might contribute to gastrointestinal symptoms through various mechanisms, including alterations in gut motility, heightened visceral sensitivity, immune activation, and changes in gas and SCFA production. Some individuals with IBD/S have found relief from symptoms through interventions like probiotics, prebiotics, and dietary adjustments aimed at modulating the gut microbiota [41]. Dysbiotic microbiota can trigger and sustain gut inflammation by interacting with the immune system, compromising gut barrier function, and producing pro-inflammatory substances. This understanding has spurred the investigation of microbiota-targeted therapies such as fecal microbiota transplantation (FMT) and probiotics as potential complementary treatments [42].

Obesity is characterized by alterations in gut microbiota's composition, often marked by reduced microbial diversity and changes in specific bacterial taxa. Dysbiosis in obesity may contribute to metabolic dysfunction through mechanisms such as increased energy extraction from the diet, altered adipose tissue metabolism, inflammation, and insulin resistance [43]. Strategies for modulating the gut microbiota, including dietary interventions, prebiotics, probiotics, and FMT, are being explored as potential approaches to manage obesity and its associated metabolic complications [44]. Diabetes, encompassing both type 1 and type 2, is marked by changes in gut microbiota composition. These alterations often involve decreases in beneficial butyrate-producing bacteria alongside increases in potentially harmful pathogens [45]. This dysbiosis can contribute to metabolic dysfunction, inflammation, and insulin resistance through various mechanisms, including compromised gut barrier function, sustained low-grade inflammation, and altered bile acid metabolism [46]. There's growing interest in modulation of gut microbiota through dietary changes, probiotics, and fecal microbiota transplantation (FMT) as potential strategies for enhancing metabolic regulation and mitigating the risk of diabetes-related complications [46].

2.5. Environmental factors

Exposure to environmental pollutants, such as heavy metals and pesticides, can evidently impact composition of gut microbiota and contribute to gut dysbiosis. These pollutants exert their effects through various mechanisms, including direct toxicity to microbes, disruption in the gut barrier function, modulation of immune responses, and induction of inflammation [47]. Heavy metals like arsenic, lead, mercury, and cadmium directly inhibit the growth and metabolism of gut bacteria, thereby disrupting microbial homeostasis by interfering with essential cellular processes and enzymatic activities [48]. Similarly, pesticides such as organophosphates, carbamates, and pyrethroids possess antimicrobial properties and may selectively inhibit the growth of specific bacterial species in the gut [49].

Exposure to environmental pollutants has found to compromise integrity of the gut barrier, resulting in increased intestinal permeability, commonly referred to as "leaky gut" [50]. This phenomenon allows pollutants, microbial components, and inflammatory molecules to pass from the gut lumen into the bloodstream, triggering systemic immune responses and inflammation [51]. Environmental pollutants can also influence immune responses within the gut, causing shifts in the composition and function of the gut microbiota [52]. These pollutants may activate pro-inflammatory immune pathways or suppress anti-inflammatory responses, creating an inflammatory environment that promotes growth of pathogenic bacteria. Chronic inflammation in gut alters the availability of nutrients and substrates required for microbial growth, leading to the proliferation of pro-inflammatory microbial species and disrupting the delicate balance of microbial-host interactions [53].

3. Conclusion

The gut microbiota plays an essential role in our metabolism by producing SCFAs and actively maintaining homeostasis. A diverse and balanced gut microbiota competes with harmful pathogens for nutrients and space, preventing their colonization. Beneficial bacteria also produce antibiotics that inhibit growth of harmful species, reinforcing the intestinal barrier and preventing toxins and infections from entering the bloodstream. Dysbiosis, of the gut microbiota, has been associated with various diseases, including allergies, autoimmune disorders, metabolic syndrome, and IBS. Diet and lifestyle significantly influence the composition of gut microbiota, making them essential for gut health and disease prevention. Dietary and lifestyle modifications, such as reducing unnecessary antibiotic use, managing stress, and creating a healthy gut environment, can support a diverse and balanced microbiota. Diet rich in fiber from whole grains, fruits, vegetables, and fermented foods encourages the growth of beneficial bacteria while limiting the proliferation of harmful ones. Limiting processed foods, sugary snacks, and saturated fats also helps prevent dysbiosis. Additionally, regular exercise, stress reduction, and adequate sleep are crucial for maintaining microbial balance. While exercise enhances microbial diversity and balance, chronic stress and poor sleep quality can disrupt this equilibrium. The intricate relationship between nutrition, lifestyle, and gut microbiota extends beyond digestive health to impact the immune system, metabolism, and mental well-being. Therefore, adopting a holistic approach that includes dietary adjustments, stress management strategies, and mindful living habits is essential for cultivating a healthy gut microbial ecosystem and promoting overall health and vitality.

CRediT authorship contribution statement

Sharvari S. Pandit: Writing – review & editing, Writing – original draft, Visualization, Validation, Project administration, Methodology, Investigation, Formal analysis, Data curation, Conceptualization. Prabhu Meganathan: Writing – review & editing, Writing – original draft, Validation, Supervision, Resources, Project administration, Conceptualization. Hemamalini Vedagiri: Writing – review & editing, Supervision, Project administration, Investigation.