The bacteria in your body are estimated to outnumber your own cells by 10-to-1. It’s a crazy thought. In terms of overall numbers, you are more bacteria than “you”. That’s because your body is an ecosystem. When everything works correctly, your cells and the bacteria live in harmony and often even work together. And when one system gets out of balance, you may find yourself sick.
This is especially true in your gut, where hundreds of bacterial species reside. Some of these bacteria are bad for you—they can cause diarrhea or upset stomachs when they are too numerous.
Others are good for you, helping you breakdown your food into digestible parts and keeping you regular. With all these bacteria in one place, it’s no surprise that your gut (your stomach and intestines) is one of the major focal points of your immune system, which is designed to protect you from infections. In fact, your gut houses more immune cells than just about any other part of your body.
Your “Gut” is Teaming with Bacteria, But Why?
There are so many different types of bacteria in the gut that scientists have called the environment the microbiome. This is just like the collection of genes is called the genome or the collection of all your proteins is called the proteome.
Why are there so many bacteria in your gut?
While we tend to think of the inside of the intestines (the “lumen”) as inside of us, it is actually exposed. When we eat and drink, we expose our intestine to countless amounts of bacteria. Our body protects us in a couple of different ways. The intestinal lining provides a physical barrier that keeps pathogens (bad bacteria, viruses, and parasites) from entering the body. When this structure breaks down, which can happen when you are ill, you can get “leaky gut”. This makes it easier for pathogens to enter your body. The same thing happens to your gums when you have gum disease.
Also, in a healthy gut, immune cells in your body secrete immunoglobulins (antibodies) against pathogens, binding them and preventing them from infecting you.
Your immune system is constantly surveying the environment, making sure that it is up-to-date against whatever you are coming in contact with. In some cases, the system can break down with some pretty disastrous consequences. For example, HIV rapidly destroys the immune system in the gut, which leads to a radically altered gut morphology and leaky gut.
Antibiotics Kill Bacteria and Can Cause Stomach Problems
When you have an imbalance of bacteria in the gut because of diet, medicine, illness, or an immune response, you can have digestive problems. When you have an infection and take antibiotics, the antibiotics not only kill the infection, they may kill many different bacteria types in your gut. This can lead to an imbalance, resulting in diarrhea. It’s not surprising that diarrhea is one of the common side effects of antibiotic treatments—up to 30% of antibiotic treated patients develop diarrhea. It’s a small price to pay to get rid of a potentially nasty infection. But certainly nobody wants to trade in one infection for digestive discomfort.
Probiotics Repopulate the Good Bacteria in Your “Gut”
So what are probiotics? Probiotics are the opposite of antibiotics. Antibiotics kill bacteria, while probiotics are bacteria. Probiotics help repopulate the good bacteria in the gut. These are the bacteria that keep you healthy. Probiotics can have several benefits. They can alter the pH (acidity) of the gut to allow or prevent the growth of other types of bacteria. Probiotics can directly compete with bad bacteria for nutrients and space, preventing the overgrowth of these bacteria. They can also stimulate the immune system, increasing your ability to defend against any unwanted visitors.
Taking Probiotics Helps Counteract Antibiotics Side Effects
Many people wonder “can I take probiotics while I’m on antibiotics?” Well researchers have looked at using probiotic supplements to combat antibiotic-associated diarrhea (AAD). In a recent issue of the Journal of the American Medical Association(JAMA), researchers took 63 of these studies—which represents over 11,000 patients—to see whether using probiotics can help with AAD. Susanne Hempel, PhD, of the Southern California Evidence-Based Practice Center, and colleagues found that probiotics helped decrease the risk of developing AAD by 42%.
The study is important for a few reasons. First, it’s huge. Combining the results from 60 different studies eliminates a lot of the individual flaws with smaller studies. A study this large means it is very unlikely that the statistical analysis will be in error. That’s why this study is in JAMA—one of the two most important medical journals in the United States (the other is the New England Journal of Medicine).
Second, because it comes from 60 studies, there were many different combinations of probiotics used. The authors say most of the studies used Lactobacillus-based formulas, although the study also included studies that looked atBifidobacterium, Saccharomyces, Streptococcus, Enterococcus, and/or Bacillus probiotics. This suggests that it is not just one type of probiotic that can help keep your gut in balance.
No Significant Differences in Effects Between Patient Types
Finally, the authors found no significant differences in effects between patient types. The probiotic effect was not significantly different between children, adults, and seniors; men and women; or between racial or ethnic groups.
This study is specific to AAD, it stands to reason that probiotics may be helpful in other cases where the microbiome is out of balance. Alterations in the gut environment have been observed not just in AAD and digestive diseases, but in mental health diseases, autoimmune diseases, infection, and diabetes. It’s unlikely that there will be a study of this size looking at probiotic use in these diseases, but the work by Hempel and colleagues goes a long way to validating the concept that probiotics can help restore normal function in the gut.
What is the difference between probiotics vs antibiotics? The Answer is in your Gut.
The best treatment for flu, cough, and cold is your own active immune system. Help it with plenty of fluids, nutrition, rest, exercise and hand washing.