Unless you've been living under a rock, you've likely heard the buzz swarming the topic of probiotics in recent years. But one such topic that's just as important (or perhaps even more so), is prebiotics—the stealthy form of fiber that fuels the healthy-inducing fire courtesy of probiotics.
"Prebiotics are the nondigestible carbohydrates, or fibers, that serve as the 'food' for our gut-healthy bacteria—probiotics," explains Lauren O'Connor, MS, RDN, RYT, registered dietitian at Nutri Savvy Health. "These healthy fibers include inulin, fructooligosaccharides, galactooligosaccharides, beta glucans, pectins, and resistant starches." So how do we get them? Well, we eat them of course! Read on for 12 of the best prebiotic foods, according to nutritionists.
You've already taken the first step in healing your gut by fitting in those daily doses of probiotic-rich, fermented foods. Good for you! But that's just Part A. That's because when you eat probiotics without changing your fast-food, high-carb, and bad-fat diet, it's as useless as drinking decaf coffee during an all-nighter. Studies have shown that probiotics are unable to colonize and mend your gut microbiota when you continue to eat a saturated-fat-heavy, fiber-free, unhealthful diet.
It turns out that probiotics don't like pizza, burgers, and french fries. They're into a fiber-rich, plant-based diet. Which is why Part B is that you not only have to eat probiotics to reap their corrective benefits but also prebiotic foods: food for your gut bugs!
What is the gut microbiome and how does it work?
Before we delve into the "why," here's a little about the "what:" The human gut consists of 100 trillion live, symbiotic, bacterial microbes that influence our nutrient absorption, metabolism, mental health, immune function, and digestive system. (Yeah, they're pretty important.) Like all living things, our belly bugs need food in order to survive and do their job—and they rely on us to feed them.
You could say they're not too picky. In fact, they'll eat whatever leftovers your body doesn't use for energy or can't break down. The only problem? Many of us regularly eat easily-digestible foods that don't have leftovers. Simple, refined carbs and junk food are processed to be readily absorbed, so your body quickly uses up their sugars as energy, or stores it as fat, leaving nothing for your lower gut. So your gut bugs starve, deprived of the food they like best: "prebiotics," such as complex carbs and various types of plant fibers.
When they get the proper foods, microbes can ferment them into short-chain fatty acids, compounds which nourish the gut barrier as well as help prevent inflammation and mend insulin sensitivity—all three things essential for weight loss. They also have the proper fuel to perform other regulatory functions, like keeping your appetite in check and your skin glowing. Ready to get started? Below we've collected a list of the best prebiotic fuels that boost the effectiveness of your gut reset and set you well on your way to a slimmer, happier you.
Why you need to eat a variety of prebiotic foods.
Experts recommend eating a variety of the following foods, as each offers unique fibers, and different microbes like to munch on different types. This way, you also increase your microbial biodiversity, which researchers have found is crucial to a healthy gut. And even if you haven't jumped on the probiotic bandwagon just yet, you should probably introduce these foods into your diet anyway; studies show that just adding prebiotic veggies to an unhealthy diet can begin to alter the composition of our gut by strengthening our good microbes. (Yes, they're still in there!)
Without further ado, here is our list of the 15 best prebiotic foods to nourish your microbiome and feed probiotics.
You're not the only one who loves chocolate—your gut bugs do, too! A recent study at Louisiana State University found that gut microbes in our stomach ferment chocolate into heart-healthy, anti-inflammatory compounds that shut down genes linked to insulin resistance and inflammation. What's more, a study published in the American Journal of Clinical Nutrition found that those who consumed drinks with higher percent cocoa solids saw an increase in the beneficial microbes Bifidobacteria and Lactobacilli as well as a decrease in undesirable gut microbes called Clostridia. Enhance the effects by pairing chocolate with some apple slices: The fruit speeds up the fermentation process, leading to an even greater reduction in inflammation and weight. To reap the most benefits, pick a chocolate with the highest percentage of cocoa solids.
Their claim-to-fame might be as a muscle-repairing, potassium-rich wonder fruit, but did you know bananas can also lead to better gastrointestinal health? They're an excellent source of prebiotics: nondigestible carbohydrates that act as food for good gut bacteria. So excellent, in fact, that they have not one, but two sources! One is (say it with us, now) fructooligosaccharides (FOS), a cluster of fructose molecules that feeds your beneficial Bifidobacteria bacteria, a species which is typically in low concentrations in obese people. And when they're green, bananas also act as a source of resistant starch—yet another form of prebiotic. A study in the journal Anaerobe found women who ate a banana twice daily as a pre-meal snack for 60 days experienced an increase in good bacteria levels and a 50 percent reduction in bloating. And that's not all, check out what else these yellow fruit do in the 21 Amazing Things that Happen To Your Body When You Eat Bananas!
Think of every bean or lentil like a little weight-loss pill. That's because pulses, like lentils, split peas, beans, and chickpeas are a source of "resistant starch." They pass through the small intestine intact, meaning these leftovers can move into the large intestine as food for your gut bugs. The microbes ferment them into a fatty acid called butyrate, which helps to turn off the genes that lead to inflammation and insulin resistance. A recent study in the Journal of Functional Foods found that when you eat resistant starch, your gut biome gets stronger. Your beneficial bacteria literally get a workout digesting the stuff, becoming more dominant and leading to a healthier gut. Curious how to fit pulses into your diet? Check out these 25 Recipes and Ideas for Pulses.
When nutritionists tell you to "eat the rainbow," that includes white! Onions are one of the best sources of the gut-healthy, soluble fiber called oligofructose, a natural source of inulin which the gut uses to spring clean as well as increase the numbers of good bacteria. In one Canadian study, subjects who were supplemented with oligofructose not only lost weight but reported less hunger than those who received a placebo. Researchers discovered that the subjects who received the fiber had higher levels of ghrelin—a hormone that controls hunger—and lower levels of blood sugar.6254a4d1642c605c54bf1cab17d50f1e
Now we know why mom told us to eat our greens. A study published in the journal Nature Chemical Biology found that leafy greens, such as the weight-loss wonder spinach, contain a unique long-chain sugar molecule known as sulfoquinovose (SQ). Because of its length, SQ isn't digested in the upper GI and moves down to the lower intestine to feed your good bacteria (which is, surprisingly, a "protective" strain of E. coli!), promoting their growth in the gut. When this strain of E. coli is strong, it can provide a protective barrier in the gut, preventing the growth and colonization by bad bacteria. Good gut health isn't the only thing spinach can do for you; it's also bursting with bone-building vitamin K, immunity-boosting vitamin C, and eye-protecting phytochemicals lutein and zeaxanthin.
Oats are a great source of an indigestible form of soluble fiber called beta-glucans. These fibers not only feed your gut bugs but have also been connected with improved insulin sensitivity as well as lower levels of "bad" LDL cholesterol. While all oats contain beta-glucans, raw oats, in particular, are also a great source of resistant starch, which will provide you with its additional anti-inflammatory benefit. Shed pounds easily—and in minutes—by putting together these delicious raw-oat recipes for overnight oats that help you lose weight.
Jerusalem Artichokes are also known as sunchokes, but they're neither related to artichokes nor are they from Israel. (As it turns out, the green chokes you see in the spring will also provide you with inulin as well—just not as much.) These tubers have a nutty, slightly sweet taste and act as a great substitute for french fries. This type of artichoke is about 76 percent inulin—making them one of the foods highest in this prebiotic fiber.
Fruit, in general, is a great source of slow-digesting fiber. However, just like how all squares are rectangles, but not all rectangles are squares: all prebiotics are fiber, but not all fiber is a prebiotic. This antioxidant-rich, anti-aging berry, however, does contain prebiotic fiber. According to a study published in the journal PLoS One, rats fed wild blueberries for just six weeks showed an improvement in the balance of the gut microbiota in favor of members of the "good guy" phylum, Actinobacteria and lower in the "bad guy" Enterococcus, bacteria which can be responsible for infections. Throw some berries into your morning oats for a prebiotic double-dose!
You may know that garlic is teeming with cancer-fighting antioxidants (well, only if you prepare them properly!), but did you know these smelly bulbs can also boost your gut health? Just like onions, garlic contains high levels of a type of fiber called inulin, which feeds bacteria from the phylum Actinobacteria. Not to mention, garlic also has antimicrobial properties, which can also be a good thing for our microbiomes as it helps kick the bad guys out. In fact, a study published in the journal Phytomedicine showed that garlic hurt the bad bacteria from Clostridium but left the good guy, Lactobacilli, intact.
Yet another member of the Allium family, along with garlic and onions, leeks will help you flavor your dishes with their mildly sweet flavor. This prebiotic powerhouse is rich in the same fiber as onions, inulin. In addition to promoting a healthy gut flora, inulin can stimulate your bone health by enhancing calcium absorption, according to a study in The American Journal of Clinical Nutrition. They play a starring role in many of these Best Broth Soup Recipes for Weight Loss.
Asparagus is packed with potassium, folate, and other B vitamins. And just 8 stalks will serve up 4 grams of muscle-building protein! In terms of prebiotic foods, asparagus is about 5 percent fiber by weight, but it can be hard to digest raw—the best way to reap the prebiotic benefits. Try blending it into a smoothie, or shave it up thinly for a salad, topped off with a mustard and white-balsamic vinaigrette along with grated parmesan.
You won't look at these weeds the same way again. That's right. One of the best prebiotic sources for your gut is growing in your backyard! These bitter-sweet spring greens are bursting with fiber, antioxidants, vitamins, and minerals. They are also a diuretic, which means they can help blast excess weight by helping your body get rid of extra fluids. And studies have found that this plant is protective against obesity as well as depression, fatigue, and immune system problems because it's a wonderful source of prebiotic fibers. In fact, you'd only need 1 oz of these greens to provide you with an entire daily serving of fiber. Use them in a salad or steep them in a tea.
Although not commonly known as a source of prebiotic, apples maneuvered their way onto this list because of their pectin content. Pectin is a natural fruit fiber found in apple peels that a study published in the journal Anaerobe found was powerful enough to support the growth of the beneficial bacteria Bifidobacteria and Lactobacillus. And if you're not a peel-person, don't worry. Apples can still help build better gut health with their sources of inulin and fructooligosaccharides (FOS). Not to mention they're bursting with antioxidants and have been found to lower cholesterol as well as protect you from metabolic syndrome, coronary heart disease, and cardiovascular diesase, making them one of the Healthiest Foods for Women.
The less processed a food is, the more will travel down to your lower gut to feed your beneficial microbes. Subbing out refined grains (via white breads, white pasta, and processed cereals) for fiber-rich whole grains, such as wheat, rye, and barley, is the easiest way to eat more prebiotic foods in your diet. Studies have found that adding whole grains to your diet, even if it's just eating a cup of whole-wheat breakfast cereal, can increase levels of Bifidobacteria and Lactobacilli after 3 weeks.
These seeds are some of the best plant sources of anti-inflammatory omega-3s known as alpha-linoleic acid (ALA), which your body converts to the same helpful omega-3s found in fatty fish. They're teeming with soluble fibers—which is why both are two of the top 30 High Fiber Foods. If you've ever made chia pudding, you've witnessed the gel-forming effect of the seeds' prebiotic soluble fibers, which do the same thing in your gut, helping to repair the gut lining as well as feed your microbes. Grind flax seed fresh or keep frozen to maintain their potency, and add it along with chia seeds to yogurt, smoothies, cereals, muffins, and pancakes.