Are microbes good or bad

Microbes including bacteria, fungi, and viruses are also called microorganisms, these microbes live in our bodies and can make us ill.

There are trillions of microbes living in the human body and most of them don’t harm the body at all. In fact, they maintain reproductive health, fight against infection, and aid in the digestion of food.

We tend to focus on destroying the bad microbes forgetting that taking care of the good ones may even be more important.

Microbes, often invisible to the naked eye, are the unsung heroes and villains of the natural world.

We encounter them daily, sometimes without even realizing it. From the air we breathe to the food we eat, microbes are an integral part of our lives.

But are they friend or foe? Let’s embark on a journey to uncover the mysteries of microbes and decipher whether they are indeed good or bad.

Quick Facts About Microbes in general

Are microbes good or bad
  • Microbes actually outweigh the cells in the human body on a scale of ten to one (10:1). Over 10,000 different species occupy the human body.
  • The human body is composed of approximately 10 trillion human cells, but there are estimated to be around 100 trillion bacterial cells in and on the body.
  • Microorganisms live in harmony with their human hosts and provide vital functions necessary for human survival.
  • We have only a few harmful microbes e.g. 1 percent of bacteria that can invade our body and make us ill.
  • Microbes can be genetically engineered to produce useful products, such as insulin for diabetic patients. Their fast division rate and ability to separate desired proteins make them valuable in biotechnology.
  • Microbes are essential for a thriving ocean ecosystem. They contribute to nutrient cycling, carbon fixation, and the overall health of marine organisms.
  • Some microbes can develop resistance to antimicrobial drugs, posing a significant global public health threat. This phenomenon, known as antimicrobial resistance (AMR), is a concern for healthcare professionals.
  • The number of microbes on Earth is estimated to outnumber all other flora and fauna and outweigh them as well.

The Bad Microbes

There is strong proof that microorganisms may contribute to some non-infectious invertebrate diseases, such as coronary heart disease and some forms of cancer.

To cause an infection, microbes must enter our bodies through a point known as the portal of entry and they can enter the body through points which are;

  • Respiratory tract (mouth and nose)
  • Gastrointestinal tract (mouth oral cavity)
  • Urogenital tract
  • Breaks in the skin surface

In order to make us ill microbes have to;

  • Reach their target site in the body
  • Attach to the target site they are trying to infect so that they are not dislodged.
  • Multiply rapidly
  • Obtain their nutrient from the host
  • Avoid and survive an attack by the host immune system
  • Microbes are not always welcome in our food. Foodborne illnesses, food spoilage, and food preservation are areas where the detrimental effects of microbes become evident.
  • Beyond human health, microbes also impact the environment in various ways. Some contribute to pollution and the degradation of ecosystems, while others are essential for environmental processes.
  • Infectious diseases caused by bacteria, viruses, and other microorganisms have shaped human history and continue to pose a threat today.

Examples of some of the microbes that are bad (disease-causing) are;

  • Yersinia pestis: Bubonic plague
  • Mycobacterium tuberculosis: Tuberculosis
  • Plasmodium falciparum: Malaria
  • Escherichia coli: Food poisoning
  • Trichophyton rubrum: Ringworm

The Good Microbes

Microbes are also beneficial to the human body in many ways. Microbes are important for your skin. The health of the skin depends on the trial balance between your cells and the microbes that live on its surface.

  • Bacteria living in the gut can help humans and animals break down food. These good bacteria help maintain the conditions necessary for food digestion. The mix of microbes in your gut can affect how well you use and store energy from food.
  • Good bacteria help our body digest food and absorb nutrients and they produce several vitamins in the intestinal tracts including acetic acid, niacin, and vitamins B6 and B12.
  • White blood cells police the body looking for infections, likewise, bacteria keep white blood cells from using too much force. Bacteria help to protect the cells in the human intestines from invading pathogens and also promote the repair of damaged tissues.
  • Microbes in our intestines may play critical roles in how we absorb calories.
  • Exposure to antibiotics especially early in life may kill off healthy bacteria that influence our absorption of nutrients into our bodies.
  • Agriculture owes much of its success to microbes. From nitrogen-fixing bacteria that enrich the soil to the fermentation of food and beverages, microbes play a pivotal role in agriculture and food production. We’ll uncover how microbes are key players in feeding our growing global population.

Below is a list of some of the good microbes and what they do in the human body, especially bacteria.

  • Lactobacillus acidophilus: It treats inflammation of the vagina.
  • Lactobacillus rhamnosus: It fights against diarrhea caused by Clostridium difficile
  • Lactobacillus rhamnosus: It helps to prevent eczema in infants
  • Lactobacillus plantarum: Helps to improve the immune system barrier against invading disease-causing bacteria.
  • Bifidobacteria lactis: Improves cholesterol levels in women and in people with type 2 diabetes.


In conclusion, the question of whether microbes are good or bad doesn’t have a one-size-fits-all answer.

Microbes are neither entirely friend nor foe; their impact depends on context. Understanding their roles, from environmental stewards to disease-causing agents, is crucial in harnessing their potential for the greater good.

As science continues to unveil the mysteries of microbes, we must stay informed and strike a balance that benefits both us and the microbial world that surrounds us.

So, the next time you ponder the question, “Are microbes good or bad?” remember that the answer lies in the intricate dance of these tiny, yet incredibly influential, life forms.

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