Bacteria is everywhere. We are hyper-aware of the dangers of E. coli, Staphylococcus, Listeria, and Salmonella, so we try to make our world as healthy as possible by sanitizing and bleaching them away.
However, bacteria doesn’t only exist in the world around us; it’s inside of us all. And that’s not necessarily a bad thing.
From birth, every one of us will acquire more than 1000 unique species of bacteria in our gastrointestinal systems, or guts. We get our personal mix of gut bacteria from vaginal vs. caesarian section births; breast milk vs. formula; the bacteria on our family members and in our homes, schools, parks, etc.; and the foods we eat. Basically, we gather our gut bacteria from the world around us. Though most people share some of the same organisms, each one of us has a unique cocktail of gut bacteria that can work for and against our personal health throughout our lives. (1, 2)
The Good and the Bad
Ninety-five percent of the serotonin in our bodies is produced in the gut, keeping an open line of communication with the brain. Pain, anxiety, mood, hunger, and illness are among the things constantly communicated between brain and gut via serotonin. (4, 5)
Gut bacteria is also seen to have an impact on weight. Recent evidence has shown that the gut bacteria in people of a healthy weight is more varied than that of obese people. A study performed on mice shed a bit more light on the phenomenon: Gut bacteria from sets of human twins with one obese and one lean twin were given to baby mice. When the mice were in separate cages and eating the same diet, those with the obese twin’s bacteria gained more weight. However, when the mice were placed in a cage together, the obese mice began to lose weight as they ingested the lean mice’s feces and acquired their beneficial gut bacteria. (6)
The best way to have a healthy gut is to promote a wide variety of bacteria… but how?
Fiber. A great way to boost healthy bacteria in your gut is to eat foods with lots of fiber, which can be digested by certain gut bacteria, causing them to reproduce. High-fiber foods to include in your diet could include raspberries, bananas, pears, whole wheats, barley, bran, split peas, lentils, a variety of beans, artichokes, green peas, and turnip greens. (7) Bonus: Eating a diet rich in fruits and veggies can halt the growth of some bad bacteria. (8)
PRObiotics. Probiotics are the good guys! We can feed our guts the good bacteria through probiotic-rich foods as well as with over-the-counter supplements. Some probiotic-rich foods are kimchi, sauerkraut, yogurt and other fermented dairy products, and pickles. (9)
PREbiotic Foods. Prebiotics are “selectively fermented” foods that can boost healthy gut bacteria. (10) Basically, prebiotics feed probiotics so that they can multiply in your gut. Some prebiotic foods are Jerusalem artichokes; dandelion greens; raw garlic, onion, and leeks; avocadoes; peas; and apple cider vinegar. (11)
Feed Your Bacteria. We’ve seen that certain foods, like fiber-rich foods and prebiotics, are better at promoting good bacteria because or bodies don’t digest them. But eating these foods, we are feeding the good bacteria in our guts. Alternatively, when we eat foods that are easily digested by our bodies, we are starving our gut bacteria and they need to find other things to eat… like the lining of our guts, which can lead to inflammation and discomfort. Foods to avoid include sugars, simple carbohydrates, and processed foods. (12)