Unsung Heroes Of A Healthy Gut
Prebiotics: The unsung heroes of a healthy gut
Gut health is a hot topic, and for a good reason. We’re continually learning more about how the health of the trillions of bacteria living in our gut has on our overall health. Our gut affects everything from our blood sugar, weight, mood, and memory. A healthy gut has been linked to a lower risk of cardiovascular disease, type 2 diabetes, obesity, auto-immune diseases, and many types of cancer.
As more evidence of the power of gut health accumulates by the day, you are likely wondering how you can ensure a healthy gut. As a primary care and lifestyle medicine physician, I regularly discuss the importance of gut health with my patients. In this article, I’ll specifically hone in on how we optimize our gut health with prebiotics, the fuel source for healthy gut bacteria. I’ll cover what prebiotics are, how they lead to improved health, and some actionable steps you can start taking today to optimize your prebiotic intake and overall gut health.
We have about 39 trillion bacteria that live along the lining of our colon, and their health is inextricably tied to our overall health. The health of those bacteria really depends on whether or not they get fed the right food or prebiotics. That’s right. Even our bacteria need to eat. So while probiotics are living strains of healthy bacteria, prebiotics are the fuel source for those healthy bugs. Prebiotics are found mostly in plants. They are things we can’t digest that end up in our colon, where they feed our healthy gut bugs. And the healthy gut bugs reward us with beneficial compounds for our health that we call postbiotics.
Notice I wrote that prebiotics are things we can’t digest. These are things that we would otherwise poop out, except we don’t. When postbiotic compounds go to the colon, healthy gut bacteria can ferment these compounds and, in doing so, provide us with beneficial postbiotics in exchange.
There are several types of prebiotics, and most originate from plants. Two types of prebiotics, fiber and resistant starch, are found exclusively in plants. Another type, polyphenols, are micronutrients originating from plants that are rich sources of antioxidants. Sometimes small amounts of polyphenols are found in animal products, but these always originate from the plants in their diet. Lastly, polyunsaturated fats that are not absorbed in our gut can serve as prebiotics. An example of this would be the omega 3 fatty acid ALA found in walnuts.
In the presence of prebiotics, our healthy gut bacteria produce beneficial postbiotics, the most notable and well-studied class of these being short-chain fatty acids (SCFAs). SFCAs have a whole slew of beneficial effects. One specific SCFA, butyrate, feeds the colonocytes, the cells that line the large intestine, increasing their thickness and overall health. Butyrate also influences genes that control cell replication and could explain why it seems protective against mutations that lead to colon cancer.
The powerful effects of postbiotics don’t just stop at the gut. Postbiotics enter the bloodstream, where they perform all kinds of magic. Some examples include the following:
They regulate blood sugar levels by improving insulin sensitivity.
They improve cardiovascular health by reducing inflammation, cholesterol, and LDL levels.
They regulate our mood.
They improve our memory and ability to learn.
You can’t reap the benefits of postbiotics if you don’t have enough healthy bacteria. You won’t have enough healthy bacteria if you don’t have fuel for that healthy bacteria. This is why optimizing our prebiotic intake is the key to gut health.
Take it from someone who has seen both sides of a healthy gut. For years, I suffered from chronic gas and bloating and erratic bowel movements that were sometimes hard, sometimes soft, and rarely something I looked forward to doing. Throughout medical school and residency training, I ate a standard American diet rooted in meat, dairy, and processed foods and devoid of much whole plant food. I was diagnosed with irritable bowel syndrome (IBS), which afflicts as many as 1 in 7 adults in the United States. IBS is caused by a lack of healthy gut bacteria, leading to a breakdown of the intestinal lining.
As I transitioned to a whole food plant-based diet, these symptoms have resolved over time. I now happily eat what I want when I want, and I don’t worry about digestive issues. I also regularly look forward to my 2-3 satisfying bowel movements every morning.
If this gut health bliss sounds like something you’re lacking, here are some steps you can take to optimize your prebiotic intake and improve your gut health:
Eat mostly plants (or only plants if that’s your thing). If getting enough prebiotics is the priority, and prebiotics all originate from plants, it benefits us to prioritize whole plant foods at every meal. Aim for 80% whole unprocessed plant food as the basis of your diet. Each meal is an opportunity to feed our good gut bugs or starve and deprive them. So if you want to show your gut bugs some love, make sure to load up on whole plants.
Go low and slow. Slowly increase the amount of plant food and fiber you are eating. This tip is especially true if you aren’t used to eating a lot of fiber in your diet or when incorporating foods that you’ve traditionally had symptoms of food intolerance, like gas and bloating. I highly recommend reading Fiber Fueled by Dr. Will Bulsiewicz. It is an excellent primer for those wanting a deeper understanding of gut health, and it includes a 28-day plan to help you get your gut back into health by slowly incorporating more variety of plant foods into your diet.
More varieties of plants = better gut health. Variety is the spice of life, and, it turns out, variety is also best for your gut health. Every plant has a distinct type of fiber, which feeds a different and specific type of bacteria. Eating various plants means more diversity of healthy bacteria, which leads to better health. Experts recommend that people wanting a top-level microbiome eat at least 30 different types of plants per week, and there’s no upper limit. Get your 30 varieties in by eating various fruits, vegetables, nuts, seeds, whole grains, and legumes. By increasing the diversity and health of your gut, your healthy bacteria will be pumping out postbiotics like it’s nobody’s business.
Incorporate more resistant starch. Resistant starches are starches we can’t digest, and, as a result, they end up as food for the bacteria in the colon. There’s a neat trick to increase the resistant starch content in the food you’re already eating. Simply by cooking grains (like rice and oatmeal) and starches (like potatoes) in advance and then cooling them down in the fridge, you turn some of the starch into resistant starch. Cooked potatoes that have been boiled and cooled, for example, will have close to twice as much resistant starch (4.3g/100g) compared to boiled potatoes eaten right after cooking (2.4g/100g).
Eat the rainbow. In addition to increasing bacterial diversity, eating various colors of plants also ensures you get a variety of polyphenols, found in the various pigments in different fruits and vegetables. There are over 8000 different polyphenols found in plants, and they all provide unique health benefits. Polyphenols can’t be directly absorbed, so they end up unchanged as prebiotics in the colon. We absorb the postbiotic antioxidants created by our healthy bacteria after they ferment the polyphenols.
Consider adding a prebiotic supplement. Many prebiotic supplements are varieties of insoluble fiber, like acacia fiber, guar gum, and psyllium husk. Prebiotic fiber supplements shouldn't replace your food, but if you are experiencing symptoms related to poor gut health, adding a prebiotic supplement can often help.
Ultimately what I have learned from my own experience and what I empower my patients with is that we have a huge amount of control over our gut health. And a healthy gut starts by optimizing the food we feed ourselves and our bacteria.
Disclaimer: This article is for educational purposes only and NOT intended to diagnose, treat, cure, or prevent any disease or psychological disorder. Always consult your physician or another qualified healthcare provider with your questions about your medical condition and before starting or using any diet, dietary supplement, herbal remedies, or other health programs