Bacteria: More Good than Bad and Ugly

Only 10% of bacteria are “bad” or pathogenic (disease-causing) while the other 90% are “good” or non-pathogenic. In fact, they are necessary components for human life.

Many times when people think of bacteria they associate them with disease. Commercials abound for cleaning wipes that sterilize (kill) “99.5%” of bacteria and viruses on household surfaces. However, the reality is that only 10% of bacteria are “bad” or pathogenic (disease-causing) while the other 90% are “good” or non-pathogenic. In fact, they are necessary components for human life.

Bacteria and You

Many times bacteria are found to live in symbiotic relationships with other organisms. “They [bacteria] receive room and board in exchange for labour and chemical currency” (typically in the form of nutrients).1 Bacteria play a very important role in the large intestine. In the womb, babies are essentially sterile but by the age of 2 have acquired through their environment the complement of bacteria that will inhabit their gut throughout adulthood, also known as gut flora.2 “The human gut houses a staggering 10 to 100 trillion microbes from 500 to 1,000 species—more than 10 times the number of cells that make up the human body.”3 So essentially, you are more bacteria than human!

Gut flora are responsible for aiding in digestion (they have enzymes to breakdown foodstuffs that we don’t) and making vitamins. Another important function they serve is usually not noticed until the gut flora is killed by taking well-intentioned antibiotics for an infection. Sometimes people will suffer from what is referred to as antibiotic-associated diarrhea. When many of the “good” bacteria are killed by the antibiotics, the “bad” bacteria can gain a foothold and cause diarrhea.

Competition among bacteria is very important for keeping populations of pathogenic bacteria in check.

Gut flora are in constant competition with pathogenic bacteria (acquired through the environment) for nutrients. Gut flora can alter the gut environment making it unsuitable for growth by pathogenic bacteria. They also produce bacteriocins, which are chemicals that kill other bacteria. Competition among bacteria is very important for keeping populations of pathogenic bacteria in check. So think twice about using those antibiotic wipes for general cleaning—a sterile environment is not a good thing!

A recent study found that “skin harbors at least 182 species of bacteria, many of which were previously unknown.”4 Differences in the complement of bacteria on the skin were found between individuals (more than 71% were unique to an individual) and between men and women.5 Again, one of their main roles may be competition to keep the numbers of “bad” bacteria low.

Exposure to bacteria early in life has also been linked to lower incidences of allergies in children. Children who live on farms (supposedly exposing themselves to many bacteria by working with animals and being outside) are less likely to develop allergies than children not living on farms.6Allergies are caused by the body overreacting to a foreign agent (such as pollen, dust, etc.). The bacteria are thought to “train” the immune system to react appropriately. So the next time you see your kid stuffing their mouth full of dirt, stay calm and think about all the “training” their immune system is getting.

Consuming Bacteria Can Be Good for You

The term probiotics (literally “for life”) refers to dietary supplements that contain live cultures of bacteria or yeast. Many dairy products, such as yogurt and milk, are considered probiotics. Dannon has recently marketed a yogurt which contains the bacteria Bifidus Regularis [sic], which the company claims helps to regulate your digestive system.7 Probiotics are sort of the Rid-X of the human septic system. The bacteria that compose the probiotics do not remain in the body permanently but may be effective when normal gut flora has been diminished. Research on probiotics is preliminary, but their market worth ranges in the billions. Probiotics are currently being investigated for their effectiveness in curing obesity, colitis, colon cancer, and irritable bowel syndrome.8


Although unseen and often given a bad rap, most bacteria are not a detriment to human life but rather necessary for human life. Although the Fall has affected bacteria (as everything else) resulting in mutations that can lead to bacteria that cause disease, this was not part of God’s original design. Fortunately, much of God’s original design of beneficence can still be seen in these microscopic wonders that inhabit our gut, skin, and every environment on planet earth.


  1. Bijal Trivedi, “Slimming for Slackers,” New Scientist, September 28, 2005,
  2. Ibid.
  3. Ibid.
  4. Jennifer Viegas, “Bacterial ‘Zoo’ Thrives on Human Skin,” Discovery Channel, February 5, 2007,
  5. Ibid.
  6. Roger Lauener, et al., “Expression of CD14 and Toll-like Receptor 2 in Farmers’ and Nonfarmers’ Children”, The Lancet 360, no. 9331 (August 10, 2002): 465-466, doi:10.1016/S0140-6736(02)09641-1.
  7. Ibid.
  8. Trived, “Slimming for Slackers;” and Chung, “It’s a Jungle in There.”


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