“Going with your gut”, a common phrase meaning to go with your feelings and intuition now has another meaning. Beyond a sixth sense, going with your gut can now reference that you are focusing on something much larger- about 100 trillion times larger, in fact. You read right, 100 trillion times. What am I talking about? If you guessed gut bacteria (aka the microbiome, microbiota, or microflora) you are correct!
But what exactly is gut bacteria, what does it do for my health, and how can I support a community of 100 trillion cells?!
100 trillion? Really?
Yup, turns out the microbiome and Zimbabwe’s currency (their 100 trillion dollar note actually exists) have something in common. If you are thinking that 100 trillion sounds like a crazy large number, you are not alone. Many friends and family members have asked me a variation of the following question: “How do 100 trillion cells fit in my gut?” My response usually involves something to the extent of “Bacteria are really, really small.”
That’s cool and all, but what are bacteria?
So glad you asked! Bacteria are tiny (microscopic!) single celled organisms. Bacteria are extremely prevalent on Earth, having been found in disparate locations ranging from 40 miles up in the atmosphere to miles underneath the ocean’s surface. Additionally, bacteria are found throughout the human body.
Large communities of bacteria on the skin, in the gut, and reproductive organs make up distinct profiles, classified as the microbiome. Microbes can be divided into classes based on different characteristics, with some classes contributing to health, while others classes cause infection and disease. For the microbiome, there are three predominant microbial classes that have been associated with a “healthy” microbiome: Bacteroidetes, Actinobacteria, and Firmicutes.
What’s with all the health hype?
Recent research has shown that the microbiome positively promotes health by aiding in digestion, providing energy and nutrients that are difficult to acquire, outcompeting harmful bacteria, and training the immune system. Sounds great, right? I think those are enough reasons for all of the recent interest and coverage. However, it’s not the only piece of the puzzle.
Just like most good things have fine print, the microbiome is no exception. Altered microbiome profiles have been linked to chronic diseases like obesity, inflammatory bowel conditions, cancer, and cardiovascular disease, and much is still unknown about these interactions and associations.
So what can I do to nourish my microbiome?
Nourishing your microbiome starts with nutrition. You may have heard of the terms prebiotics and probiotics. These “biotics” are the two primary ways you can support your microbiome. Breaking down the two words can get at what these things actually do for the microbiome. “Biotic” means relating to, or resulting from living things, especially in their ecological relations. “Pre” means before and “pro” means to stimulate or support. So just by looking at the words alone, you can get a pretty good sense of what they do for the microbiome.
Basically, prebiotics are the “food” used by microbiome. Prebiotics are composed of complex carbohydrates that can predominately be digested by microbiome. Some examples of prebiotics include inulin, polydextrose, fructooligosaccharides (FOS), and galactooligosaccharides (GOS).
On the other side of the equation are the probiotics. Probiotics contain microbiome-promoting bacteria. Common probiotic strains include Bifidobacterium, Streptococcus, and Lactobacillus, which have been shown to support a healthy microbiome. However, just because you may see these strains listed on food ingredients does not necessarily mean these foods will have a probiotic effect. For this reason, in order to be classified as a probiotic, the specific strains must result in proven health benefits and/or contain more than 108 organisms per gram (i.e. 100 million bacterial cells/gram) at the end of manufacturing.
Where can I find prebiotics and probiotics?
In case the words inulin, FOS, and GOS don’t mean much to you, the following foods are rich sources of prebiotics: bananas, honey, whole grains, artichokes, leeks, onions, and garlic. In addition, you can find prebiotics in fortified foods and beverages. Aim to eat about 2-30 grams per day of prebiotics, which can be achieved from eating ¼ of an onion, 1 banana, and about ½ cup whole wheat flour (or something that has been made with ½ cup whole wheat flour. As for probiotics, yogurt, buttermilk, kefir, kombucha, kimchi, sauerkraut, miso, tempeh and other fermented foods contain probiotics. If you’d rather get your dose of probiotics in the form of a supplement, go for it.
Myths about microbiome
What about the relationship between low-calorie sweeteners and the microbiome?
You may have heard or read the most recent article that linked low-calorie sweeteners and negative modifications to the microbiome. However, coverage from media stories often leaves out critical details (design, results and limitations) from research studies and most often tells and sells a story based on one study that is counter to what the totality of scientific research in the area concludes.
The majority of media stories about the role of low-calorie sweeteners on the microbiome use the same few studies performed in animal models, and try to pose that the findings have direct implications to human health. Excuse me? This should not happen and these articles should shift their focus to research stemming from clinical trials (the gold standard). In case you were wondering, there are no published studies that assess the relationship and impact of low-calorie sweeteners on the microbiome in humans.
So there you have it, yet another reason to go with your gut to support your overall health. Try to incorporate prebiotics and probiotics into your diet. Don’t let the myths and misinformation about the microbiome bog you down, but rather, stick to the science and your gut will be good to go!