The Relationship between the Immune and Digestive Systems

I’ve always connected my immune system to what I eat, probably because from a very young age my father told me that eating oranges would keep colds away. As I’ve grown and become involved in athletics in high school, I’ve also learned that this relationship has an important effect on athletes.

 Source: Ben Aguillon

As humans we eat a variety of different things, and unfortunately some of these things contain bacterias or contaminants that can be harmful. It should be noted that most of the bacteria we eat is good bacteria that is needed for various functions of the immune and digestive systems, but certain bacterias cause illness. Bacteria is on literally everything, and because of this the digestive systems takes in quite a bit of it. In order to prevent illness, the immune system has proteins and chemicals that kill off the bad bacterias. The immune system has cells, organs and chemicals that help differentiate between the two types of bacteria, and then based on that judgement, the immune system can eliminate it. When bad bacteria is detected, the immune system protects the rest of the body from being infected by it and then kills the harmful bacteria.

Source: NASA’s Marshall Space Flight Center

The digestive system and immune system further work together in preventing the spread of bacteria. The linings of the stomach and intestines act as a corral to keep bacteria from spreading to other more susceptible parts of the body. The body also naturally builds up an immunity to bacterias that are encountered often, which helps prevent illness as well.

The two systems are tied so closely together because (almost) everything that enters the body enters through the mouth. Therefore, athletes need to be aware of the nutrition they are receiving. Let’s say that there is an athlete who constantly eats only McDonalds and Red Bull, and another who eats plenty of fruits and vegetables and lots of lean protein. The latter athlete will perform better because they are receiving nutrients that can better serve their body when they perform. If an athlete habitually eats things like raw meat from sketchy restaurants or gas station sushi, their body has to spend more time and energy on fighting harmful bacterias which robs them of energy that would improve their performance.

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Everyone should be aware of what they’re eating, but especially athletes. Eating a diet rich in nutrients will increase performance and ultimately aid them.