Prebiotics, which are the fiber that probiotics eat, have been around for millenia, but they’ve only come into our collective consciousness in the last decade or so. Prebiotics are vital to our gut health, but they can have the unpleasant side effects of gas and bloating. Here’s everything you need to know about taking them.
What Are Prebiotics?
To answer the question of what prebiotics are, let’s start with our microbiome. That’s the complex system of bacteria that resides on and in our bodies—the average person carry anywhere from about 2 to 6 pounds. For the sake of this discussion we’ll skip talk of the bacteria that live on us, and focus on where they concentrate most inside us: our gut. The bacterial balance in our intestines is a pivotal factor of our wellness, as most of our immune system resides there.
The “good” bugs we want to have as the major player in our gut are known as probiotics, and they keep us healthy in countless ways, including important ones like preventing cancer. That’s why you’ve undoubtedly heard you should be consuming them regularly, either as a supplement or in foods like yogurt, kombucha, and kim chi.
What’s less well known is the fact that in order to replenish your probiotic supply, your probiotic colony needs food. Hey, everything needs to eat in order to multiply! Rather than eating and taking probiotics nonstop, you can give them the food required to multiply on their own. What they eat is insoluble fiber, which is also known as resistant starch. It’s one of the two types of fiber contained in the foods we eat. Insoluble means our guts don’t digest it or get nutrients from it, which does happen when we eat soluble fiber. Instead, our stomach passes that fiber along intact, and the probiotics in our intestines consume it. It’s called resistant starch because it resists digestion by our digestive systems.
Prebiotics Make Us Happier
You may be aware that our guts are responsible for the majority of the serotonin, a primary feel-good chemical needed for emotional wellbeing, that our bodies manufacture. The link between wellness and our intestines is irrefutable for physical and emotional health, and just like probiotics can help keep us happy, taking prebiotics has been proven to improve our emotional wellness. Prebiotics reduce our production of the stress hormone cortisol, and have an anti-anxiety (anxiolytic) effect.
How Do We Get Prebiotics?
Before recent years, prebiotics weren’t something you could ingest on their own. We got them solely through the food we eat. Foods high in prebiotics include onions, jicama, and bananas, to name a few. You’ve likely eaten lots of foods with them and never even noticed. Once people became more aware of the importance of prebiotics, we began to add them to processed foods to increase their nutrient value; prebiotics are typically labeled as “inulin” in packaged goods. In recent years the food, beverage, and supplement markets have been flooded with powders, capsules, bars, chips, drinks, and more touting the benefits of prebiotic fiber.
Prebiotics and Bloating
As mentioned, prebiotic fiber occurs naturally in numerous foods. It is no coincidence the more resistant starch a food contains, the more unpleasant gut-related side effects it may have. For example, sunchokes, formerly known as Jerusalem artichokes, are among the highest in insoluble fiber of all foods. They taste like a cross between an artichoke and a potato, and have deliciously creamy flesh. And they are known colloquially and in the chef world as fartichokes.
Because our digestive system can’t break down insoluble fiber, the fiber enters the latter stages of our digestive system intact. There, probiotics eat it, and as that happens the fiber ferments as well as pulls water into our intestines. That fermentation—which occurs quickly despite sounding like something that takes months, not minutes or hours—creates gas. Oddly enough, it isn’t considered a bad thing when the cause of gas and bloating is fiber—instead, it's considered a normal part of the process. That said, it certainly isn’t an experience most of us are comfortable with or want as a part of our days.
Can You Take Prebiotics Without Experiencing Bloating?
Here is where science differs from anecdotal evidence. I was inspired to write this article because I’ve written and spoken publicly about prebiotics for a good few years now, and I’m an avid fan of the idea of consuming them, but for the life of me I cannot digest them. Ever. No matter what. Science says when you first start taking prebiotics, you can expect an increase in gas and bloating, but after a couple weeks it will reduce to the levels experienced before. Specifically, “The volume of intestinal gas produced...increased by 37% at the beginning of HOST-G904 administration...and decreased down to preadministration level after 2 week administration.”
Prebiotic supplement brands may claim that their particular product doesn’t cause gas or bloating, and that if you experience those effects, you aren’t taking the right prebiotic. That logic is perfectly sound, with one brand stating, “People supplementing with digestion resistant starch sometimes complain of bloating and discomfort, especially when first trying the product or when increasing the dose. This is often the case with other prebiotics. However, this problem is generally temporary and is likely related to the microbiome adapting to increased prebiotic levels: The bacteria that can use the prebiotic more efficiently (and produce less problematic gas as a side effect) increase in numbers over time as the amount of prebiotic in the diet increases.”
The Bottom Line
If you want to try taking prebiotics, start slow and small—this may be the key to avoiding gas or bloating. Gradually increase your dosage until you reach the full amount, and, according to prebiotic suppliers, you’ll do well. Certainly this is the case for some people, as the industry continues to flourish.
For others like me, it doesn’t matter what product I try, or what quantity of it. I have otherwise excellent digestion, and gas and bloating aren’t complaints in my general life, so that isn’t the issue. Yet when I was gifted a pound of prebiotic fiber powder by a company, I discovered that even a fraction of a teaspoon made me bloated for the day. I have since given up on taking prebiotics and chosen to leave well enough alone.
You shouldn’t take prebiotics if you have SIBO (small intestine bacterial overgrowth) or if you’re sensitive to FODMAPs, which are a specific group of sugars that ferment in your gut differently than others and also exacerbate SIBO symptoms. For everyone else, prebiotics are an important part of our diet, just don’t be too surprised if when you eat or take them, it feels like you’re doing your probiotic colony more of a favor than it’s doing you.
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