What can cause an imbalance in gut flora populations?

Heather Campbell
 min read

What can cause an imbalance in gut flora populations?

What can cause an imbalance in gut flora populations?Most of us have, at one time or another, suffered from an imbalance in gut flora without knowing it. We’ve certainly suffered the consequences.

As a general rule, an imbalance of the gut flora can be caused by genetics, food, regular constipation, antibiotics, or surgery to mention a few. Stress and infections in the digestive tract are also to blame.

Ecosystem imbalance may be related to one of the three elements of the functional tripod. But the most vulnerable part of this intestinal ecosystem is the microbiota (intestinal flora).

Read on to learn how we can avoid it, and what its unpleasant indications are.

What can cause an imbalance in gut flora populations? Introduction

This is called dysbiosis (imbalance of the intestinal flora). The most common causes of this dysbiosis are:

  • surgical procedures
  • through food
  • constipation
  • vaccinations
  • early colonization conditions induced through birth and breastfeeding
  • stress
  • antibiotic intake (the impact is individual, even for a single intake and even more so in case of repeated intake)
  • digestive infections
  • genetic predisposition

Any disturbance of this microbiota (intestinal flora) can have important consequences, because, in eubiosis (balance), the intestinal flora ensures the maintenance of a good nutritional balance within the digestive tract and effective defenses against external aggressions.

This is due to a barrier effect (it prevents pathogenic bacteria from settling) and a modulation effect of cytokines, which are crucial in the regulation of the immune response.

The different causes of this imbalance, alone or in combination, are responsible for the disruption of this ecosystem and its possible consequences in the short, medium and long term, depending on our environment (what we breathe, eat and live) but also on our genetic vulnerability.

Surgical procedures

Regardless of whichever organ is removed, abdominal surgical procedures alter the anatomical relationships of the digestive organs and disrupt their function.

Bloating, transit disorders or mood disorders (depressive feelings) are not necessarily related to dysbiosis.

Therefore, a specialized stool examination should be performed. Dysbiosis may be pre-existing and inapparent to the procedure. The surgical act, as well as the anesthesia and the induced stress, can reveal it.

Moreover, any surgical procedure, on the abdomen or elsewhere, is accompanied by the use of anesthetic, analgesic and antibiotic drugs which, in addition to triggering or aggravating dysbiosis, will affect the enterohepatic cycle.

However, the dysfunctions of the intestine and the liver are intimately linked.

Related post: Small intestine and large intestine: Functions of these two organs

Through food

Eating too much sugar and fat can be a factor in dysbiosis.


Constipation is generally defined as having few, hard stools that are difficult to expel.

This prolonged transit time has an impact on the colonic flora and upstream on the intestinal flora. Constipation is accompanied by bloating, which is often painful, and odorous gas emissions.

Stool examinations have shown that constipated people have a dysbiosis with an imbalance of the intestinal flora, both in the fermentation flora and in the putrefaction flora.

In addition, this dysbiosis in relation to constipation has an impact on the production of digestive serotonin, which can lead to mood disorders.

Related postWhat role do gut bacteria play in digestion? Health insights


Contact with the vaccine forces the recipient’s immunity to shift to the newcomer. The objective is that all injected germs or viral particles lose their virulence.

It is quite possible that the information decoded by the general and intestinal immune systems may be wrong.

Neither the vaccine dose nor the vaccine particles (injected viruses, bacteria or toxins) nor their excipients are tailored to each individual.

Therefore, a blind system tested on animals is introduced into our very sophisticated, complex and fragile immune system. The general immunity reacts with signs such as fever, pain, fatigue, etc.

This condition, which resembles disease behavior, corresponds to inflammation of the brain, which is secondary to intestinal inflammation. This reacts in symbiosis with the general inflammation.

In addition, several studies have shown the presence of viral particles of the measles vaccine virus in the cerebrospinal fluid and intestinal tract of vaccinated children.

And let’s not forget that vaccine adjuvants are not without toxicity because of their content in mercury, aluminum, etc.

Through birth and breastfeeding

Remember that the newborn’s intestinal system is sterile at birth (see intestinal system).

The colonization of his digestive tract begins after the rupture of the water bag.

The newborn is suddenly immersed in a rich and varied bacterial universe and is rapidly colonized by the maternal vaginal, intestinal and cutaneous microbiota as well as by environmental microorganisms.

Continually exposed to new bacteria, its microbiota will then diversify. From the third day of life, bacteria are implanted.

Delivery (natural or cesarean) and breastfeeding strongly influence the speed of implantation of the intestinal microbiota in the newborn.

The increase in cesarean deliveries and the decrease in breastfeeding may be key factors in the increase in allergies.


Any stressful situation affects the gut, for example, diarrhea before a school exam. This is also the case in irritable bowel syndrome, gastritis, bloating, etc.

Dissatisfaction, anger and fear, to name a few common feelings, have an influence on our gut and naturally promote the establishment or maintenance of imbalances.

Any situation experienced as stressful triggers a general adaptation syndrome in three phases:

  1. Alarm
  2. Resistance
  3. Exhaustion

These phases are accompanied by biological reactions, particularly from the alarm phase, a secretion of adrenalin accompanied by a significant leakage of magnesium from the cell and its urinary elimination.

This leads to a significant decrease in all the body’s magnesium reserves. This drop in magnesium is responsible for worsening the state of stress.

Magnesium depletion also has many important health consequences:

  • At the level of the intestinal flora: Disorders of intestinal absorption and disruption of tight junctions, which cause intestinal hyperpermeability
  • A decrease in the production of energy by the body’s cells (therefore fatigability)

Taking antibiotics

Antibiotics have a considerable influence on the intestinal microbiota.

Several studies have shown a link between the early use of antibiotics and the occurrence of certain diseases.

One study found a link between early antibiotic use (before age 5) and the development of Crohn’s disease.

Similarly, antibiotic use in the first year of life is related to the risk of developing asthma in childhood, especially in infants who received four or more courses of antibiotics.

Antibiotics influence the intestinal microbiota composition from the first days after the start of the antibiotic therapy to reach a maximum percentage of modification after 4 days.

However, depending on the individual and/or intercurrent diseases, the original microbiota gradually returns to its initial profile.

Each individual reacts differently.

Also in adults, the occasional development of chronic disorders following antibiotic therapy has been noted, sometimes favoring opportunistic infections, especially if the treatments are long and repeated.

Digestive tract infections

Diarrhea or gastroenteritis is often foodborne and can lead to:

  • Stunted growth in children with increased immediate or delayed morbidity and mortality.
  • Increased susceptibility to other infections
  • Malabsorption
  • Repeated infections
  • Malnutrition

Digestive tract infections can be fatal.

Protection from pathogens (that can make you sick) is provided by the intestinal ecosystem:

  • the mucous membrane and its secretion of mucin
  • the microbiota
  • the systemic and local immune system

Their ability to penetrate the organism depends both on the virulence of the pathogens themselves and on our defense factors, but also on the ability of these pathogens (viruses, parasites, etc.) to hijack our inflammatory responses in order to promote their growth and thus to infect us.

The most frequent infectious causes of this dysbiosis are parasitosis, mycosis and enteropathogenic bacteria.


Parasitosis often manifests itself in stomach pains, transit disorders with soft, liquid or hard stools, bloating, gurgling and sometimes by itching in the anus or elsewhere on the skin, a state of fatigue or allergy.

Intestinal parasites are frequently associated with and transmitted by dirty hands or by parasitic and undercooked food.

Prevention is based on simple hygiene rules. You must:

  • Sufficiently cook pork and beef
  • Wash your hands, especially before cooking or eating
  • For those who like tartare, make sure you are eating quality meat that is not parasitized.
  • Soap your hands after a bowel movement and brush your nails

In tropical countries, the conditions of transmission are the same. Prevention consists of drinking water disinfected with Micropur for example (purification tablets), or mineral water with the capsule intact before consumption.

To avoid transcutaneous parasitosis, you should not walk in stagnant water or rivers, but only in seawater.


They are extremely common.

High-dose antibiotic therapy or repeated doses, without probiotic protection, weakens our dominant bacteria or even decimates them. Candida albicans then take over and disrupt the intestinal immunity and the systemic immune system.

Genetic predisposition

Let’s take the case of twins as an example. The microbiota of monozygotic twins (identical twins, one egg) are more similar than those of dizygotic twins, and those of dizygotic twins are more similar than those of unrelated individuals.

To explain this similarity (or particular distribution), some scientists suggest the existence of a genetic factor determining the composition of our intestinal flora.

It would result in similarity but not the same identity (the differences being related to environmental conditions).

What can cause an imbalance in gut flora populations? Conclusion

It’s easy to see, after reading the above, that while certain factors such as genetics and childbirth don’t allow us to control any imbalance, how we conduct our day to day activities has a strong impact on gut health.

Food, medicines, environment and so many other factors really are up to us.

About Heather Campbell

As a nutritionist, my field of specialization is science-based nutritional advice but more importantly, it is my goal to share capturing and inspiring stories, examples and solutions which can help plus-size individuals overcome their specific difficulties. Read More