There have been numerous studies linking gut bacteria and human health. The modern Western diet and wide availability of antibiotics have changed the number and variety of bacteria that live in our gastrointestinal tract, which appears to have poor overall health effects. Surprisingly, even our immune systems are affected by this global shift in gut flora. According to a new study, gut bacteria protect against sepsis and other serious infections by interacting with an important immune protein called IgA.
Infectious Disease: A Global Threat
Many people think of infectious illness as a declining issue in the modern world. With the advent of antimicrobial treatment, vaccination programs and modern sanitation, infectious diseases have become far less common throughout most of the globe.
However, infectious disease still remains a sizeable risk. Many people in the developing world remain at risk of catching a deadly microbial infection. In addition, infants, elderly people and the immune compromised are at risk even in the developed world. Last, many pathogenic bacteria are becoming resistant to antibiotics and other treatments, creating an increase in deadly infections.
Despite these challenges, there is still one important line of defense against infectious disease: a healthy immune system. Our body has a complicated system of cells and proteins designed to seek out and attack bacteria and viruses that can cause illness. According to new research, our gut bacteria play an important role in supporting a healthy immune system.
Gut Bacteria and the Immune System
Although most people do not realize it, our gut bacteria — and thus our diet — can have far-reaching effects on the immune system. Certain types of gut bacteria that are becoming increasingly common can cause inflammation in the gastrointestinal tract, which can eventually lead to colon cancer. In addition, certain types of gut bacteria can actually protect against inflammation and disease.
Most of the research on gut bacteria and the immune system have focused on the interaction between our flora and immune activity in the gastrointestinal tract. However, a new group of studies suggests that our immune system as a whole may be affected as well. Your risk of infections in the lungs, bloodstream, and other areas of the body may be impacted by what you eat and how this affects your gut flora.
How Some Gut Bacteria Protect Against Sepsis
A recent study looked at infants at high risk of developing sepsis, a dangerous and potentially deadly condition in which the bloodstream is infected with pathogenic bacteria. One group of infants was given a synbiotic supplement, which contains both probiotic bacteria and the prebiotic foods needed to feed them, while the other did not receive the supplement. The infants who were given the synbiotic supplement had a 40 percent reduction in sepsis and sepsis-related deaths.
How can gut flora affect the chance of getting a blood infection? Another study, this time looking at mice, found that mice were more resistant to sepsis when they had a large number of a species called Proteobacteria. In fact, their blood levels of IgA, an important immunoglobulin, rose when they took supplements with this species of bacteria. This is significant because IgA is crucial in combatting bacterial sepsis.
On the other hand, the wrong balance of GI flora may contribute to disease and even death. Mice that had large numbers of pathogenic bacteria in their guts had more inflammation, even in areas of the body outside of the gut. In addition, these disease causing bacteria were likely to be found in their lings and bloodstream, contributing to both sepsis and acute respiratory distress.
The Importance of Prebiotics and Probiotics
Clearly it is important to keep your gut flora balanced. However, this can be a challenge in modern industrial civilizations. Our foods are often deficient in the healthy bacteria needed to maintain optimal health. This allows less beneficial bacteria to take over the GI tract, creating inflammation. Many people take a probiotic supplement or make an effort to eat foods rich in positive GI bacteria. This may not be enough on its own. Researchers and medical scientists are increasingly recommending that people also take a supplement with prebiotics, which are the soluble fiber and other foods that help to feed healthy GI flora so they can flourish.
There is a great deal of conflicting information about healthy lifestyle. However, research is clear that having the right GI flora can be important and even crucial to our health and well-being. The bacteria that live in our guts can have effects on our immune system, our bloodstream, and even our mental health. Taking a supplement with both probiotics and prebiotics may help to make us healthier in a variety of ways.