We all need prebiotic fiber in our diets in order to keep our guts healthy. Prebiotics feed the good bacteria we have in our gut and keeps our entire digestive system working properly. And as with all nutrients, the absolute best way to get more prebiotics in our diets is naturally. So here’s my list of the nineteen best foods that contain prebiotics and that are easy to find in your local grocery store.
The old adage about an apple a day keeping the doctor away may or may not be true, but an apple a day will help keep your gut healthy! A study done in 2016 found that the pectin in apples improves the gut barrier function, promotes the healthy gut bacteria, and helps to decrease inflammation in the gut. Apples make a great snack any time of day, but you can also use them to top oatmeal and cereal.
Both the almond nut meat as well as the almond skin were shown in a study in Anaerobe to have prebiotic effects. Participants who ate almonds saw increases in the beneficial bacteria strains of Bifidobacteria and Lactobacilli as well as a decrease in Clostridia, a strain of undesirable bacteria found in the gut.
When I was growing up, asparagus was considered a “fancy” vegetable and very difficult to find (unless you wanted the canned version), but these days, it’s easy to find and easy to prepare, and it’s packed with the prebiotic fiber inulin, as well as potassium and B vitamins. Blanched, steamed, sauteed or roasted, asparagus is a great vegetable to add into your weekly diet.
Bananas are great for the gut, but! you need to eat them before they are fully ripe. Unripe bananas have resistant starch – a form of indigestible fiber – but as they ripen, the amount of resistant starch goes down. If you’ve never had a green banana, they’re actually quite good! They have a slight tartness to go along with the typical banana sweetness, and their flesh is firmer. And like apples, bananas are great when used as a cereal or oatmeal topper.
Barley isn’t as popular a grain here in the US as wheat is, but it’s a lot healthier for the gut. Barley contains the prebiotic fiber beta-glucan, which has been shown to lower cholesterol, and barley also has selenium, which is good for your thyroid function and boosts the immune system. The best way to get barley into your diet is to use it as a replacement for rice or noodles, especially in soups.
Antioxidant rich, and a good source of Vitamins C and K, blueberries have also been shown to have prebiotic fiber and to be healthy for your gut. A study on PLOS ONE found that wild blueberries improved the gut microbiota of rats by supporting the good bacteria strain Actinobacteria and retarding the bad bacteria strain Enterococcus. Eat them fresh, or use them in your morning breakfast for a gut health boost.
Cocoa Powder / Chocolate
Cocoa and the chocolate that is made from it are high in polyphenols, which both help the good bacteria in our gut while reducing the growth of the bad bacteria. Polyphenols also have antioxidant and anti-inflammatory properties. In 2014, students at Louisiana State University found that in our gut, chocolate fermented into compounds that shut down genes linked to insulin resistance and inflammation. Pretty cool, huh? Another study published in the American Journal of Clinical Nutrition found that people who had drinks with a high percent of cocoa solids saw an increase in both Bifidobacteria and Lactobacilli as well as a decrease in the prevalence of the Clostridia strain (just like was shown with people who ate almonds).
Take care, though – most chocolate has a lot of sugar, which has the exact opposite effect on the gut as prebiotics. So, to reap the most benefit from chocolate, pick one with the highest percentage of cocoa solids and the lowest percentage of sugar.
There was a time when you could only find flaxseeds in specialty groceries (remember when there was a silly stigma attached to healthy, organic foods?). Thankfully, these days, even the big chain grocery stores will have flaxseeds (sometimes in the produce section, sometimes in the baking aisle). These little seeds are so good for you and your gut. They have omega-3 fats, antioxidants, and both soluble and insoluble fiber. One study found that flaxseed helped to lower cholesterol, and the fiber in flaxseeds promotes healthy digestion and regular bowel movements.
You can certainly sprinkle them as a salad and soup topper, but because they’re so small, it’s much easier to grind them up and add them to smoothies and salad dressings.
As a member of the Allium family, garlic is positively packed with prebiotics in the form of flavonoids and inulin. A study published in the journal Phytomedicine demonstrated that garlic decreased the prevalence of the bad bacteria strain Clostridium but did no damage to Lactobacilli, a good strain. Garlic is also antibacterial and antimicrobial, so well worth adding into your diet.
Grapefruit is a superfood, with tons of health benefits. But did you know it has a whopping 12 grams of fiber per serving? That’s right - but there’s a catch: in order to get the fiber, you have to eat the pith that separates the fruit segments. That’s why the majority of nutritional lists for grapefruit list the fiber as far less than that; most people don’t eat the pith, they just scoop the flesh out, leaving most of the fiber behind. As with oranges, the grapefruit pith is edible. But it’s very chewy and especially along the outside, much thicker than the pith of other citrus fruits. So, what to do? I recommend a whole fruit juicer, one that can grind up and pulp the entire fruit. Just be sure to add a sweeter fruit – like apples or berries – into the mix before you drink it. Or, put it in the freezer long enough for it to turn slushy.
If you find other members of the Allium family (garlic and onions) a little too harsh when it comes to taste, give leeks a try, as their taste is milder. Like other Alliums, leeks have lots of the prebiotic fiber inulin. Leeks are wonderful raw in salads, or added to your favorite soup recipe instead of onions.
A cautionary note about leeks. They’re packed with Vitamin K (one leek contains 35% of the recommended daily value for Vitamin K), which promotes blood clotting, so if you’re on blood thinners and/or have a blood clotting disorder, be careful about Vitamin K.
Mushrooms contain both alpha- and beta-glucan and essential amino acids, along with the minerals magnesium, iron, potassium, zinc, and calcium. Mushrooms stimulate the growth of good gut bacteria and stimulate the immune system. They also contain antioxidants, and have been shown to lower cholesterol, reduce inflammation, and protect the liver.
Oats are packed with beta-glucans, and raw oats are also high in resistant starch. Not only are oats prebiotic, but they have been proven to lower cholesterol and help control appetite. Overnight oats are a fantastic way to get raw oats into your diet, but cooking the oats still has lots of prebiotic fiber to benefit your gut.
We’ve already mentioned two other members of the Allium family – leeks and garlic – so it should be no surprise that onions of all varieties have the same beneficial prebiotic fiber. The best part? Onions retain all of their prebiotic benefit even after being cooked. Add them to soups, stews, and chilis, and they’re great roasted, too.
The cute little green nuts are a good source of prebiotic fiber, and they’re also a great source of protein for vegetarians and vegans.
Pulses are legumes; specifically, legumes whose seeds are found inside pods. Chickpeas, lentils, split peas, and beans like kidney beans and black beans are all pulses. All of them are incredibly healthy for you, high in prebiotic carbohydrates, and all feed your good gut microbiota. Chili is a great way to get more beans into your diet (add onions to really boost the prebiotic effect), and hummus is the perfect snack to eat more chickpeas.
Spinach and other leafy greens provide the gut with a special long-chain sugar molecule called sulfoquinovose. While not an actual prebiotic fiber, SQ performs a similar function. The SQ molecule is so long, it’s able to make its way down to the lower intestine, where it feeds a protective strain of E. coli that helps keep the gut barrier strong and prevent the growth of bad bacteria.
The same cautionary note about Vitamin K holds true for spinach; moderate your consumption if you’re on blood thinners or have a blood clotting disorder.
Watermelon is a decent option for good gut health. While it doesn’t have a lot of fiber, its water content is so high (92%!), it’s fantastic for keeping the body hydrated – and good hydration is key for good digestive health. It also has more lycopene – an antioxidant linked to lower risk of heart disease, eye disorders, and cancer – than any other fruit or vegetable – and it’s high in Vitamin A, which is important for both eye and skin health.
Wheat bran – the outer layer of the wheat grain – is an excellent prebiotic. It contains a special kind of fiber, made of arabinoxylan oligosaccharides, that have been proven to increase the percentage of Bifidobacteria in the gut, and also reduces other gut issues like gas and cramping. You can eat wheat bran by itself, or sprinkle it into your oatmeal or cereal.
There are plenty of other foods that are high in prebiotics: chicory root, seaweed, dandelion greens, konjac, burdock root and jicama root. But they can be more difficult to find. My list above contains foods that are generally available at any chain store.
While it would be nice if we could all get all of our prebiotic fiber from natural food sources, most of us can’t manage it. That’s why I created Great Gut Extra Strength Prebiotic Fiber. Supplementing your daily diet with Great Gut will ensure you’re giving your gut everything it needs to stay healthy!