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Microbes & Immunity Management of obesity

years, however, the significance of the gut microbiota in treatment. Given the prominent role of the gut microbiota
obesity has garnered increasing attention, revealing its in obesity progression, it presents a promising target for
profound impact on host energy storage and metabolic novel therapeutic strategies. Future research should focus
processes. Pioneering research has demonstrated that on better understanding the relationship between obesity
5,6
altered gut bacterial composition, specifically, a decrease and gut microbiota, uncovering the mechanisms by which
in the abundance of Bacteroidetes and an increase in the microbiota influences obesity, and evaluating the safety
7
Firmicutes, correlates with obesity. Moreover, studies and efficacy of microbiota-targeted therapies as potential
involving the transplantation of microbiota from obese treatments for obesity. 11
and lean individuals into germ-free mice have shown
that microbiota from obese individuals promote greater 2. Human gut microbiome and its relation
fat accumulation, highlighting the potential role of to obesity
gut microbiota in the development of obesity. This The gut microbiota plays a central role in obesity
3,7
observation, combined with emerging theories, such as
the hypothesis of metaflammation, suggests that genetic progression, affecting microbial diversity, metabolic
adaptations that evolved to combat infectious diseases pathways, inflammation, immunity, and hormone
may inadvertently contribute to the modern obesity regulation. Dysbiosis in obesity results in imbalanced
epidemic. Understanding the evolutionary origins and the bacterial populations, increased inflammatory markers,
8
complex interplay between genetics, the microbiome, and reduced gut barrier integrity, and alterations in
environmental factors is essential for addressing this global metabolic functions. The gut microbiome influences
health crisis. 9 energy homeostasis, shaping fat accumulation, insulin
resistance, and immune responses. While beneficial
Obesity is also strongly linked to an elevated risk of a microbes offer anti-inflammatory and metabolically
range of diseases, including cardiovascular complications, protective effects, harmful bacteria and microbial-
diabetes, respiratory issues, and certain cancers. While derived metabolites contribute to chronic inflammation
the causes of obesity are multifactorial and not yet fully and metabolic disorders. Understanding these intricate
understood, contributing factors include unhealthy mechanisms may pave the way for microbiota-targeted
eating habits, sedentary lifestyles, environmental interventions, offering potential therapeutic strategies to
influences, and genetic predisposition. One of the most improve metabolic health and combat obesity. In obese
12
intriguing environmental factors linked to obesity is the individuals, the gut microbiome is often characterized by
gut microbiota, which has been shown to play a pivotal intestinal dysbiosis, involving reduced microbial diversity,
purpose in the development and progression of obesity imbalanced bacterial composition, and altered metabolic
and other metabolic disorders, such as diabetes and non- functions. This dysbiosis leads to a loss of beneficial
alcoholic fatty liver disease (NAFLD). The gut microbiota, commensal bacteria, an overgrowth of pathogenic or
a complex ecosystem of microorganisms inhabiting the conditionally pathogenic microbes, and an overall decline
human gastrointestinal tract, includes bacteria, fungi, in microbial gene richness. Several studies have reported
viruses, archaea, and protists. With a total weight of reduced gut microbiome diversity in obese populations,
3
about 1 – 2 kg and containing more than 100 times the suggesting that a less diverse microbiota may contribute to
number of genes in the human genome, the gut microbiota metabolic disturbances and obesity development.
contributes to various essential physiological functions.
These include digesting and absorbing nutrients, defending A widely observed trend in obesity is an increased
against harmful microbes, and maintaining immune Firmicutes/Bacteroidetes ratio, with Firmicutes being
system balance. However, when the microbiota becomes more abundant and Bacteroidetes being significantly
dysbiotic, meaning it falls out of balance, it can contribute reduced. Some studies have confirmed this pattern across
to a range of diseases, including obesity. Gut dysbiosis is various populations, indicating a correlation between
thought to influence obesity through multiple mechanisms, gut microbiota composition and obesity. However,
13
including disruption of energy homeostasis, altered lipid newer research suggests that relying solely on phylum-
synthesis and storage, modulation of central appetite and level classification may be oversimplified, as differences
feeding behaviors, and promotion of chronic low-grade within bacterial genera and species reveal more nuanced
10
inflammation. While several effective interventions for microbiome changes in obesity. For instance, while certain
obesity exist, such as healthy lifestyle changes, weight- Firmicutes species, such as Clostridium, Lactobacillus, and
reducing drugs, and bariatric surgery, maintaining long- Ruminococcus are found in greater abundance in obese
term weight loss remains a challenge. In addition, side effects individuals, the levels of Faecalibacterium prausnitzii (also
associated with drugs and surgeries can further complicate within the Firmicutes phylum) decrease. This species is

Volume 2 Issue 4 (2025) 41 doi: 10.36922/MI025160036