Probiotics and Fiber: Why You Need Both for Better Health
Probiotics and fiber work together, not against each other, to build a genuinely healthy gut. One introduces the beneficial bacteria your digestive system needs. The other feeds and moves that bacteria through your system. Skip either one, and you're only getting half the picture.
Quick Facts About Probiotics and Fiber
Fiber and probiotics serve two different but complementary roles in digestion. Fiber moves waste through your digestive tract and helps regulate blood sugar, while probiotics introduce and balance the beneficial bacteria living in your gut. A 2022 clinical trial found that combining fiber and probiotics produced significantly better metabolic outcomes than using either alone.
Aim for 25 to 35 grams of fiber daily from whole food sources, paired with a resilient, multi-strain probiotic for the most complete gut support.
Key Takeaways
- Fiber and probiotics aren't competing strategies. They work best together, with fiber acting as food for the beneficial bacteria probiotics introduce.
- A 2022 randomized clinical trial published in Translational Psychiatry found that combining fiber and probiotics significantly outperformed either one alone for improving metabolic markers and preventing weight gain.
- Most people need 25 to 35 grams of fiber daily, best sourced from whole foods rather than fiber supplements, which can cause uncomfortable bloating.
- Temporary bloating when increasing fiber intake is normal and typically resolves within a couple of weeks as your gut adjusts.
- Digestive enzymes containing cellulase can help your body break down fiber more comfortably, especially if you're new to a higher-fiber diet.
How Does Fiber Aid Your Digestion?
Dietary fiber, or simply fiber, is a healthy carbohydrate that your body can’t digest. Dietary fiber has more purposes than just maintaining your digestive health; it also helps regulate your body’s blood sugar and helps keep your hunger under control. Fiber acts like a broom, helping to keep our digestive tract clean and healthy by sweeping out waste and toxins. So, not only does fiber improve digestion, but it also helps to optimize the overall nutrient uptake and health of our bodies.
Dietary fiber comes in two forms:
- Soluble fiber: This kind of fiber dissolves in water and is found in foods like oatmeal, chia seeds, lentils, beans, and nuts. Soluble fiber helps maintain your blood glucose levels and can help lower blood cholesterol levels.
- Insoluble fiber: This fiber does not dissolve in water and is probably what you think of when you hear “fiber.” Insoluble fiber helps keep you regular, prevents constipation, and moves food through your digestive tract. Insoluble fiber is found in foods like brown rice, quinoa, leafy greens, legumes, and almonds.
Not only can a healthy diet rich in fiber help prevent constipation and digestive discomfort, but it can help reduce the risk of serious health conditions like heart disease and diabetes.
How to Increase Your Fiber Intake
Fiber plays a crucial role in digestion by aiding in the absorption of nutrients from the foods we eat.
You need 25 to 35 grams of fiber each day. A lot of people try to get their daily fiber intake with a fiber supplement, such as psyllium. I actually recommend avoiding these because they can cause uncomfortable bloating and gas! With a healthy diet rich in fresh fruit, vegetables, and whole grains, you can easily get your daily fiber intake!
If you’re working on increasing your daily fiber intake, you may find that it’s not the most comfortable experience! I hear a lot from people about the bloating and discomfort that comes with these new dietary measures. As a fellow fiber fanatic following the Beauty Detox lifestyle, I’ve been there, and it’s no walk in the park!
This is normal, and it will pass, but it’s important that you stick with it! If you previously weren’t getting enough fiber in your diet, your body is adjusting to your new, higher fiber intake. Once your body has acclimated to it, you can say bye-bye to that bloating!
Also, don’t forget to drink plenty of water when you’re upping your fiber intake. It’ll help your body adapt to all that extra fiber and flush out your system.

How Do Probiotics Boost Digestion?
If you’ve been reading the Solluna blog, then you probably know a thing or two about probiotics! I’ve even written an entire article about the differences between prebiotics vs. probiotics vs. postbiotics, so if you want to learn more about that, check that one out once you’re done reading this one! :)
Probiotics are simply the healthy bacteria that live in your gut microbiome and help keep bad bacteria in check. Probiotic bacteria are vital to promoting a healthy digestive system, boosting your immune system, reducing inflammation, and supporting your overall health.
All these good bacteria make up what’s called your enteric nervous system (ENS), your body’s “second brain” located in your gastrointestinal tract! This balance of gut bacteria— including the potentially harmful bacteria— is the key to flourishing gut microbiota, a robust ENS, and better overall health.
You can get these healthy bacteria in your diet by eating fermented foods like sauerkraut, kimchi, and kombucha, but many opt for a dietary supplement to get the probiotics their bodies need. Actually, doing both is the best way to get all the probiotic bacteria your body needs to be at its best.
However, you don’t want to just choose any probiotic supplement! I highly recommend a good SBO probiotic supplement because they’re hardier, more efficient, and they’re closer to nature.
You may be wondering now, though, where does dietary fiber figure into this?
Related: How to Choose a Probiotic Supplement
Why Fiber and Probiotics Work Better Together
Here's the part that ties it all together. Fiber acts as a prebiotic, meaning it feeds the beneficial bacteria that probiotics introduce. Without it, those bacteria have far less to work with.
A 2022 randomized clinical trial published in Translational Psychiatry tested this combination directly in patients dealing with antipsychotic-induced weight gain. The group receiving both fiber and probiotics together saw significantly better outcomes than either intervention alone, including improved insulin sensitivity and less weight gain overall.
The takeaway holds well beyond that specific population: pairing the two produces real, measurable benefits that neither delivers on its own.
The average American diet runs low in fiber and high in the sugar, fat, and sodium that feed the wrong kind of gut bacteria. Over time, that combination shows up as bloating, irregularity, and in more serious cases, symptoms tied to conditions like IBS or IBD.

Add Digestive Enzymes for the Full Picture
If fiber and probiotics are the foundation, digestive enzymes round things out.
Fiber can be genuinely hard to break down, especially if you're newer to a higher-fiber or plant-based way of eating. Solluna's Digestive Enzymes contain cellulase, an enzyme your body doesn't produce on its own but relies on to break fiber down comfortably and efficiently.
Together, fiber, probiotics, and digestive enzymes cover every part of the digestive process: feeding good bacteria, introducing more of it, and helping your body actually process what you eat.
Even if you’ve been on a plant-based diet for a while, we all have days where our digestion just isn’t as robust as it should be. It happens. :) Digestive enzymes can help there by giving your digestion that extra oomph it needs to keep you feeling light and energetic.
FAQ
Do I need both fiber and probiotics for good digestion?
Yes. Fiber feeds the beneficial bacteria that probiotics introduce, and research shows the combination outperforms either one used alone.
How much fiber should I eat daily?
Most people need 25 to 35 grams a day, ideally from whole foods rather than supplements, which can cause bloating.
Why do I feel bloated when I increase my fiber intake?
This is a normal adjustment response as your gut adapts to more fiber. It typically resolves within a couple of weeks, especially with consistent hydration.
What's the best way to get both fiber and probiotics?
A diet rich in whole plant foods covers your fiber needs, while fermented foods and a resilient, multi-strain probiotic supplement fill in the rest.
Probiotics and Fiber: Why Not Both?
Separately, probiotics and fiber are vital parts of healthy digestion and better overall health, as well as key components to both inner and outer beauty. Put them together, and you reap all their individual benefits and more!
So when it comes to probiotics and fiber, it shouldn’t be “either or.” To feel and look your best, why just go with one when both together are so much better? :)