Most of us know the typical culprits when it comes to weight gain: excess calories, sedentary lifestyle, and sometimes even hormones and thyroid disorders. There’s another cause for weight gain that comes from within your stomach itself (other than insatiable hunger): gut bacteria. Keep reading to learn about gut bacteria and the factors that affect your own, so you don’t pack on unwanted pounds.
All of us have a complex economy of naturally occurring and dietary-affected microorganisms living within our gut—billions, in fact—which you may have heard of as being divided into “good bacteria” and “bad bacteria.” This is because depending on the breakdown of different strands of microbes coexisting in your intestines and recent lifestyle factors (for instance if you just took a heavy course of antibiotics), the bacteria there can either do helpful or harmful things to your body and its various systems—digestive, immune, cardiovascular, and more.
New studies have shown that the composition of gut flora in obese and thin people actually varies, with an abundance of diverse and good bacteria in thin people that obese people seem to have less of or lack altogether. After the bacteria present in thin people was identified by studying identical sets of twins in which one twin was obese and one twin was thin, researchers found that germ-free mice who were given the bacteria present in thin people gained less weight than those who weren’t, on the same diet and regardless of exercise.
Researchers think that gut bacteria affect how you digest food and turn it into energy, with bad bacteria both causing people to store more fat and also crave more sugary, fatty foods.
Though the specific type of bacteria, Christensenellaceae, found in thin people and used in the aforementioned mice study hasn’t been approved for oral transmission in humans just yet, don’t despair. The flora and microbial ecosystem in the thin twins’ guts didn’t just have Christensenellacea; it was also overall far more diverse and populated with good bacteria than in the heavier twins.
Luckily, diet does play a role in regulating the ratio of better bacteria to bad bacteria. As nature, science, and biology would have it, good bacteria thrive on diets high in fiber, fruits, and vegetables, and low in fat, while bad bacteria survives on highly-processed foods. In fact, fiber actually causes good bacteria to grow. So until you can safely ingest Christensenellaceae, the best thing you can do to promote the balance of good and bad bacteria in your own gut is to keep processed foods to a minimum; eat a healthy intake of fiber, fruits, and vegetables; and eat as much low-sugar, homemade yogurt as you can stomach (pun intended) if you have to take a course of antibiotics, as antibiotics notoriously wipe out the good bacteria that were rooting for you right along with the bad.
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