Microbial Diversity in the Gut:

A Key Player in Chronic Noncommunicable Disease Development

 

Kanaka Durga Devi. N1*, Bharghava Bhushan Rao. P2, Sirisha Koppula1, R. Triveni1, K. Jyothi1 R. Anusha1,  K. Anil kumar1, Madhu Priya. Vanukuri1, Kammeli Siva Durga1,

Gudivada Harshini1

1KVSR Siddhartha College of Pharmaceutical Sciences, Vijayawada, Andhra Pradesh, India.

2A.M.Reddy Memorial College of Pharmacy, Narasaraopeta, Andhra Pradesh – 522001, India.

*Corresponding Author E-mail: nelluriss@rediffmail.com

 

ABSTRACT:

The human gastrointestinal tract, with its vast surface area, hosts the intricate gut microbiota, essential for regulating the immune system and energy metabolism. Chronic non-communicable diseases (NCDs) pose a global threat, particularly burdening low and middle-income countries. Urgent interventions, including vaccination, testing, public health measures, and targeted treatments, are advocated by leading scientists and the WHO. The scarcity of data on NCDs in Southeast Asia underscores the need for increased awareness and action. Unhealthy lifestyle behaviors are major contributors toNon-communicable diseases (NCDs) encompassing a range of health conditions such as cardiovascular ailments, cancer, chronic respiratory disorders, and diabetes. Disparities in access to nutritious food and physical activity exacerbate the NCD challenge, impacting disadvantaged individuals. Addressing the NCD crisis is compounded byScarce resources, a vulnerable public healthcare infrastructure, an insufficiently controlled private healthcare sector, and an increasingly aged demographic. Comprehensive strategies and global cooperation are vital to mitigate the escalating burden of NCDs.

KEYWORDS:  Gut microbiota, Non-chronicinfectious disease, Cardiovascular disease, Cancers, Food and physical activity.

 

 


INTRODUCTION:

Thehuman gastrointestinal (GI) tract is a significant interface, encompassing an expansive surface area of 259-400 square meters, through whichThe individual is influenced by environmental elements and antigens. Throughout an average lifetime, around 60 metric tons of food pass through the gastrointestinal tract, transporting a multitude of microorganisms from the surrounding surroundings. The influx of microorganisms poses a substantial challenge to the integrity and health of the gut1.

 

Furthermore, the gut microbiota engages in a tight-knit interaction with the immune system, contributing to the education and control of immune responses. This interplay is essential for the appropriate maturation and operation of the immune system, thwarting excessive inflammation while fostering tolerance to innocuous antigens2.

 

Comprehending the complex interconnection between the host and gut microbiota is a dynamically researched field, and it presents encouraging prospects for advancing therapies that target the gut microbiota to enhance human well-being3.

 

The gut microbiota development, which begins at birth and continues throughout life, is intricately linked to host metabolic and neurologic programming. This coevolutionary process between the microbiota and host is of paramount importance for maintaining health and well-being in the later stages of life4.

 

Energy metabolism significantly relies on the gut microbiota's ability to extract and store energy. They are involved in fermenting and absorbing undigested carbohydrates, which would otherwise be unavailable for the human host. The capacity to extract surplus energy from the diet has probably exerted substantial evolutionary pressure, leading to the establishment of bacteria as symbiotic entities within the human body5.

 

ORIGIN AND COMPOSITION OF GUT MICROBIOME:

Encouraging the proliferation of particular strains within a well-balanced gut microbiome offers:

 

Achieving a balanced Intestinal microbiotainvolves nurturing a diverse community of beneficial microorganisms through a combination of dietary choices, probiotic supplementation, stress management, and mindful use of medications.

 

Enhanced energy efficiency refers to the optimization of energy usage, reducing waste,and maximizing output, resulting in improved energy conservation and productivity.

 

Enhanced macrophage activity and phagocytosis amplify the immune response, enabling efficient engulfment and elimination of pathogens and cellular debris for improved immune defense and tissue maintenance.

 

The induction of mucin production stimulates the production of protective mucus, which forms a barrier and helps maintain the integrity of mucosal surfaces, promoting a healthy and resilient defense against pathogens and irritants.

 

Mucin production is induced to protect and maintain the health of the mucosal surface.

 

The potential of competitive exclusion to impede the adhesion of pathogens and prevent their colonization.

 

By augmenting antigen-specific immune responses, it lowers the risk of re-infection, thereby providing enhanced protection against future encounters with the same pathogen6.

 

 

Dominant Microbial Communities98%

 

Actinobacteria 1% to13%

 

 

Bacteroidetes 9 % to 42%

Gut

Microbiota

 

 

 

Firmicutes 30% to 52%

 

 

Other Microorganisms 2%                          

 

Lactobacillus 2%

 

 

Enterobacteria 1%

 

 

Streptococci 2%

 

 

Fig 1: bacteria percentage in gut microbiota

 

ROLE OF MICROBIOTA:

The gut microbiota has a pivotal role in upholding immune equilibriumresponse by facilitating the Initiation and maturation of thegastrointestinal immune system7,8.

 

Additionally, the mucosal immune systemExercises a pivotal influence in regulating the makeup and conduct of the intestinal microbiome.

 

Furthermore, its influence on effector T cells within the gastrointestinal (GI) tract, the gut microbiota also exerts influence on aspecialized subgroup of CD4+ T helper cells referred to as Th17 cells. These unique T cells are recognized for their capacity to release particular interleukins, specifically IL-17A, IL-17F, IL-21, and IL-22. The generation of these cytokines by Th17 cells plays a role in diverse immune reactions and inflammatory mechanisms occurring within the gastrointestinal system9.

 

In addition to its role as a potent inflammatory cytokine, IL-17 has the ability to amplifyContinued inflammation is perpetuated through the stimulation of the expression of tumor necrosis factor (TNF)-α and IL-1β in different cell types. The heightened inflammatory response contributes to the ongoing progression and persistence of inflammatory diseases10.

 

Low-grade inflammation is linked to obesity and metabolic syndrome, potentially resulting in a range of health issues like type 2 diabetes, cardiovascular disease, and stroke. Managing these conditions requires a multifaceted approach that includes a combination of dietary changes, exercise, and medication when necessary. One important aspect of managing obesity and metabolic syndrome is making dietary changes.Enhancing insulin sensitivity and mitigating inflammation can be achieved by diminishing the consumption of processed and high-fat foods, while simultaneously increasing the consumption of fruits, vegetables, and lean proteins. Additionally, limiting sugar and alcohol intake can help to promote weight loss and improve overall health17.

 

The Influence of Diet on Gut Microbiome:

Protein, fat, and carbohydrates constitute the main elements in human diets that have a substantial influence on the gut microbiota's makeup. Metabolites stemming from these dietary constituents, notably short-chain fatty acids (SCFAs) like acetate and butyrate, represent the final outcomes of microbial-assisted breakdown within the gastrointestinal tract (GIT). Extensive research has been conducted on SCFAs generated by the gut microbiota, revealing their profound physiological impact on the host's well-being17.

 

An individual's diet composition, particularly the balance between fat and fiber consumption, plays a pivotal role in shaping microbial diversity. When contrasting someone following a high-fat, low-fiber diet with an individual adhering to a high-fiber, low-fat diet, the latter typically shows a reduced presence of pathogenic bacteria18.

 

CHRONIC NON-COMMUNICABLE DISEASE:

Persistent non-communicable ailments (NCDs)Present a substantial worldwide health concern and pose a considerable threat to both human well-being and progress. Low and middle-income countries bear the primary brunt of these diseases, imposing a substantial burden on their populations19.

 

In response to the urgent need for effective interventions, leading scientists and the global health body, commonly known as the World Health Organization (WHO)have elevated to call for action20. They are advocating for the implementation of strategies that can address the current challenges and improve the situation. These strategies may include widespread vaccination campaigns, enhanced testing, and contact tracing efforts, the promotion of public health measures such as mask-wearing and physical distancing, and the development of targeted treatments or therapies. The aim is to utilize the available interventions to their full potential and mitigate the impact of various health issues, such as infectious diseases or other public health crises21,22.

 

The limited data availability concerning the trends, impact, and determinants of chronic non-communicable diseases in Southeast Asia countries underscores the need for increased attention to this issue. By providing comprehensive information on these diseases, we aim to raise awareness and focus efforts on curbing the epidemic23,24

The changing pattern of unhealthy lifestyle behaviors poses a significant risk for non-communicable diseases (NCDs). These diseases are chronic conditions that typically develop over time and are not caused by infectious agents. The major NCDs responsible for a significant number of deaths worldwide include25

Cardiovascular diseases (CVDs): These encompass a spectrum of health conditions that impact the cardiovascular system, including coronary artery disease, heart attacks, and strokes. Factors contributing to the risk of cardiovascular diseases involvesmoking, an unhealthy diet, sedentary lifestyle, obesity, hypertension, and diabetes.

Cancers:Multiple forms of cancer, comprising lung, breast, colorectal, and prostate cancers, add to the worldwide load of non-communicable diseases (NCDs). Factors that elevate the risk of cancer encompass the use of tobacco and alcohol, an unhealthy diet, physical inactivity, exposure to certain chemicals and pollutants, and genetic factors.

Chronic respiratory ailments: Health conditions such as chronic obstructive pulmonary disease (COPD), asthma, and occupational-related lung diseases. occupational lung diseases are categorized under this classification. Tobacco use, contact withair pollution, indoor and outdoor allergens, as well as occupational hazards are some of the key risk factors for chronic respiratory diseases.

Diabetes is a metabolic disorderCharacterized by elevated levels of glucose in the bloodstream.Non-insulin-dependent diabetes mellitus, which accounts for the majority of diabetes cases is closely associated with lifestyle variables such as poor food, lack of physical exercise, and obesity. 

 

Unhealthy lifestyle choices have a crucial role in the development and progression of many NCDs. Poor dietary habits, lack of physical exercise, usage of tobacco and alcohol, and exposure to environmental pollutants are all modifiable risk factors that can be targeted through preventive measures and health promotion strategies. By adopting healthier habits and addressing these risk factors, Individuals can lower their risk of getting NCDs and enhance their overall health.26

 

CAUSES DISEASES THAT ARE NOT COMMUNICABLE:

The burden of noncommunicable illnesses is influenced by past and cumulative hazards, whereas current population exposure to risk factors determines the future burden. While the key risk factors for noncommunicable disease epidemics are more complicated than those for infectious illnesses, they are well-established and play a role in the majority of such occurrences27.

 

These risk factors are often shared among the most common kinds of noncommunicable illnessesof they can be modified. Furthermore, Although there may be some quantitative changes, these risk variables work similarly in all parts of the world28,29.

 

RISK CHRONIC NON-COMMUNICABLE DISEASE FACTORS:

Age, sex, and hereditary factors are considered non-modifiable determinants of chronic diseases. These factors are beyond the control of an individual and cannot be altered. Age is a non-modifiable determinant because as individuals grow older, they may become more susceptible to certain chronic diseases due to natural physiological changes that occur over time. Sex, referring to biological differences between males and females, can also influence the risk of developing certain chronic diseases. Lastly, hereditary factors or genetic predispositions inherited from parents or ancestors can play a role in determining an individual's susceptibility to specific diseases.

 

 

FIG 2: Death rate in non-communicable disease

 

BIOLOGICAL FACTORS:

High Blood Cholesterol :

Cholesterol levelsA diet strong in saturated fats and lacking in fibermay cause a buildup of cholesterol in the circulation, raising the risk of a heart attack.

Saturated fats may be found predominantly in animal products such as fatty red meats, full-fat dairy products such as butter and cream, and egg yolks. These foods can contribute to elevated cholesterol levels when consumed in large amounts.

Trans fatty acids, which are widely present in partly hydrogenated oils used in processed foods, can elevate cholesterol and increase the risk of heart disease. A diet high in soluble fiber, on the other hand, can help decrease cholesterol levels. Soluble fiber binds to cholesterol in the digestive tract, preventing it from being absorbed into the circulation.

Fruits, vegetables, whole grains, legumes, and nuts are high in soluble fiber.In addition to dietary factors, other lifestyle choices such as physical inactivity, smoking, and excessive alcohol consumption can also contribute to High blood cholesterol levels contributing to an increased risk of heart disease.

Managing cholesterol levels often involves a combination of dietary changes, regular exercise, and, in some cases, medication prescribed by a healthcare professional. It is critical to get personalised advice and help from a healthcare expert while dealing with elevated blood cholesterol levels.30

 

Genetics:

In another example, individuals of Ashkenazi descent and Jewish ancestry are more prevalent.of specific genetic BRCA1 and BRCA2 mutations dramatically enhance their chance of getting specific forms of hereditary breast and ovarian cancers31.

It is important to note that while genetic factors can contribute to an increased susceptibility to certain chronic diseases, lifestyle and environmental factors also play a crucial role. Adopting good behaviours like as eating a balanced diet, exercising regularly, and avoiding tobacco and excessive alcohol usage might help reduce the riskassociated with these genetic predispositions. Additionally, regular medical check-ups and genetic testing can aid in identifying and managing potential risks32.

 

HYPERTENSION :

According to national statistics from 2003, the rates of managed hypertension were relatively low in both men and women.Just over one-quarter all men and 22% of women had hypertension under control. This highlights the need for improved management and treatment of hypertension to prevent complications and promote better overall health outcomes. It reinforces the importance of regular medical check-ups, adherence to prescribed medications, and lifestyle modifications such as physical activity and a good diet to successfully manage and control hypertension33.

 

BEHAVIOURAL RISK FACTORS:

PHYSICAL INACTIVITY:

Regular physical activity has been shown to have numerous Health advantages and can help minimize the chance of developing a variety of chronic conditionsassociated with a sedentary lifestyle34.

Engaging in moderate amounts of physical activity, taking into account thePositive health effects has been linked to frequency, length, and intensity. These advantages include a lower risk of obesity, breast cancer, colon cancer, osteoporosis, hypoglycemiamental health conditions such as stress, anxiety, and depression.

TOBACCO CONSUMPTION:

Tobacco usage is a primary cause of avoidable death, with approximately four million deaths attributed to it annually according to the World Health Organization (WHO), andprojections indicate that smoking may claim one in six lives worldwide by 2030 if current trends persist..

 

CONCLUSION:

The GI tract's vast interface and its interaction with the gut microbiota are crucial for human health. Understanding this relationship offers promising therapeutic avenues. The development of gut microbiota is intricately linked to host well-being, particularly in later life.

Noncommunicable chronic illnesses posea worldwide health risk, predominantly affecting low and middle-income countries. Urgent interventions, as advocated by the WHO, are required to address these challenges and mitigate their impact.

The scarcity of data on NCDs in Southeast Asia emphasizes the need for increased attention to this issue, raising awareness to combat the epidemic. Unhealthy lifestyle behaviors significantly contribute to major NCDs, making preventive measures and health promotion essential for improving public health and individual well-being

 

ACKNOWLEDGEMENTS:

The authors are very much thankful to Management and Principal of KVSR Siddhartha College of Pharmaceutical Sciences, Vijayawada for their support and constant encouragement.

 

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Received on 23.03.2024      Revised on 21.06.2025

Accepted on 02.04.2026      Published on 01.07.2026

Available online from July 04, 2026

Research J. Pharmacy and Technology. 2026;19(7):3383-3387.

DOI: 10.52711/0974-360X.2026.00480

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