In a session sponsored by Beneo earlier this year, I learned more about how certain fibers interact with the gut’s flora. I was not compensated to write this post, and the thoughts expressions are my own. This post includes affiliate link to Regular Girl® products, I am not affiliated with any of the other product ideas linked in this post however.
If you do a search for “microbiome, health”, you’ll find over 10 million hits. Scholarly articles hit at about 165,000. Study of the human microbiome is relatively new science, and interest in this area is rapidly growing for good reason. The microbiome is the beneficial microbes and pathogens that exist throughout our body, with the largest community found in our guts.
Research theorizes that the health of gut bacteria can impact whole body systems, and possibly impact obesity, heart health, neurological status, immunity and other aspects of human biology.
There’s no question that diet plays a role in gut health, and we’ve known this for years. Diet (both nutrients and non-nutrients like fibers) have an impact on the physiological function of our guts (digestion, absorption, transit, excretion) and also impacts our immunity and endocrine secretion. The food we eat then in turn also impacts those beneficial microbes in our guts. Essentially what we eat “feeds” those healthy microbes, for better or worse.
In addition to diet, other factors impact the microbiome. Antibiotic medications generally have a negative impact, and probiotics a positive one. You probably have heard all of these terms (“microbiome”, “probiotic”, “prebiotic”), but it can get confusing, so let’s differentiate them.
What are Probiotics?
Probiotic foods introduce good bacteria into the gut. They are found in naturally in some fermented foods (like kefir, buttermilk, lactobacillus milk, yogurt, aged cheese, or kimchi). Not all fermented foods contain probiotics however. Also, some foods that claim to contain “live, active cultures” may not have the right bacterial strain, nor an adequate amount. Probiotics can also be found in supplement form (pills or powders, and more recently some refrigerated snack bars).
Probiotics in yogurt for instance, can even improve any lactose intolerance you may experience. And, including probiotics in your diet will improve gut function overall, leaving you with less gas, bloating, diarrhea or other belly troubles.
All types of fiber (soluble and insoluble) are good for you, but not all fibers are prebiotic fibers. Prebiotic fibers are a type of fiber that provides nutrition to good (probiotic) gut bacteria. We get soluble fiber (oat bran, barley, beans, nuts, some fruits) and insoluble fiber (wheat bran, whole grains, vegetables) in our diet, but prebiotic fibers have a unique impact on the gut microbiome. Prebiotic fibers are found in onions, garlic, asparagus, bananas, whole wheat, and artichokes.
Inulin and oligofructose are two supplemental prebiotic fibers of particular interest. These “functional fibers” nourish the bacteria in your colon. These fibers are used as functional food ingredients in products such as yogurt, beverages, infant nutrition products, snack/sports bars or other baked goods.
Inulin is a prebiotic fiber that has many potential benefits:
- Digestive health: Improves the balance of intestinal flora
- Weight management: This fiber helps you stay full, reduce food intake
- Strong bones: Increases calcium absorption
Oligofructose is naturally extracted from chicory root, and a subgroup of inulin. Both inulin and oligofructose stimulate the growth of intestinal bifidobacteria. Bifidobacteria are friendly bacteria and helpful to our guts. The exact molecular mechanism of how these bacteria have these positive impacts isn’t completely clear yet.
Bottom Line: What to Eat Today
This is a really exciting area of nutrition. We will continue to see more research, and more applications of these functional food ingredients. While the research grows, what we know so far seems like a pretty positive case to include probiotic foods or supplements, and prebiotic fiber in the diet. So how can you act now?
Here are my tips:
- Eat a diet rich in a variety of fruits and vegetables (Bonus: DASH Diet supports this habit!). The variety matters too, because every plant offers different nutrients that have different functions. Include the foods I mentioned that have prebiotic fibers (onions, garlic, asparagus, bananas, whole wheat, and artichokes).
- Eat a diet that includes natural probiotics. Enjoy yogurt daily, or a fermented food like sauerkraut or kimchee with a meal. Personally I think low fat yogurt is the easiest and tastiest way to include a daily probiotic, and you have the added benefit of yogurt fitting into a heart healthy DASH Diet plan. Choose a yogurt that includes probiotics on the label, and choose the ones that specify the bacteria strain (will include numbers with the bacteria name on the ingredient label). As an affiliate for Regular Girl®, I attest to the acceptability and ease of use of the product – which provides both prebiotic fiber and a probiotic (Bifidobacterium lactis), so that’s also an option.
- Enjoy whole grains and cereals to provide a variety of soluble and insoluble fibers to your diet.
- Add a prebiotic fiber like inulin to your diet. Supplements should never replace healthy eating, and you don’t have to use a daily supplement, but adding a supplement during the week may be prudent. The initial research seems very promising to me, so I recommend including some foods that use inulin or chicory root. You’d have to eat 200 bananas to get the dose of inulin you’d get from a snack bar supplement. You can choose to either use a supplement powder, or you can choose foods that include inulin on the ingredient list (like cereals or bars).