The human digestive system is far more complicated than it seems. Science has developed artificial hearts for cardiac patients and dialysis for patients with kidney disease, but nothing in medicine can really duplicate the incredibly complex series of reactions that go on in the gut. This complexity isn’t just courtesy of the endocrine system, either. It also comes from an unlikely source: the billions upon billions of bacteria that live inside of us.
“Good” Bacteria vs.”Bad” Bacteria
If you’ve ever used probiotic supplements or eaten yogurt made with live, active cultures, you might be familiar with “good bacteria.” These are bacterial strains, like Lactobacillus species, that typically populate a healthy digestive tract in large numbers. Other bacteria, like Salmonella or Escherichia coli, are often considered “bad” bacteria. When you ingest certain strains and their numbers begin to grow, you may suffer from diarrhea, vomiting, and other digestive upsets.
The thing is, “good” and “bad” are really misnomers. E. coli is present in a healthy digestive system, only certain strains cause illness. It’s also entirely possible to get an infection from “good” bacteria, like Lactobacillus. The trick is to avoid pathogenic strains, and maintain the right balance.
How do “bad” bacteria affect your digestive health?
Strains of infectious bacteria can access the digestive system via contaminated food, contaminated fluids, or even through touching a contaminated surface, then eating without washing your hands. Foods or beverages that have been contaminated with fecal matter can result in an E. coli infection. Because these germs are so similar to the bacteria your digestive system needs in order to stay healthy, it’s pretty much an ideal environment for them to grow and reproduce.
“Bad” bacteria make you sick because, as they live in the digestive system, they produce toxins. One particular group of E. coli strains produces a compound that damages the lining of the intestine. This can result in bloody diarrhea. Some strains of Salmonella attach themselves to the lining of the small intestine, and produce toxins in a similar fashion to pathogenic E. coli.
How do “good” bacteria help keep you healthy?
“Good” bacteria are a first line of defense against infectious germs. If your colonies of intestinal flora are robust, they take up space and consume resources that infectious bacteria need in order to grow and make you sick. They also help by interacting with the intestinal lining and immune system to regulate inflammation. A specific strain of Lactobacillus — L. rhamnosus — is currently being studied for its effects in helping to regulate allergic reactions.
These beneficial bacteria don’t just help your physical health, either. Many people with anxiety or depression have low levels of the neurotransmitter serotonin. Interestingly, about 90% of the body’s serotonin is actually made in the digestive tract. Studies in animals show that lactobacillus plantarum can actually help improve mood and reduce anxiety responses by increasing dopamine and serotonin levels, and reducing inflammation.
How can you improve your “good” bacteria?
The best way to improve your levels of beneficial intestinal flora are to feed and hydrate them well, and avoid doing things that will disrupt them.
- Always cook food to a safe temperature and wash your hands thoroughly before eating in order to avoid consuming infectious bacteria.
- Make sure you eat enough prebiotics — sources of fiber, like inulin, that serve as a food source for your gut flora. Choose high-fiber fruits and vegetables.
- Eat fermented or cultured foods, like yogurt, kefir, kimchi, or sauerkraut. These are natural sources of beneficial microbes.
- Avoid highly processed foods.
- Drink plenty of water. This keeps your intestinal lining healthy, and balances levels of gut bacteria.
- Antibiotics can wipe out a lot of your intestinal microbes. If you need to take an antibiotic, follow your doctor’s advice when it comes to using probiotics to help replenish your gut flora.
In many cases, “good” and “bad” are relative. Good bacteria can cause infections if they grow unchecked, and some strains of bad bacteria are actually necessary for health. By following these tips, you can keep your gut flora happy, healthy, and balanced.