How Long It Takes for a Probiotic to Work + Telling Signs

How Long It Takes for a Probiotic to Work + Telling Signs

Bacteria often gets a bad rap—but did you know that there’s such a thing as good bacteria? Probiotics, in particular, are made up of these good-for-you bacteria that survive inside your intestine after being eaten.

Probiotics have many important functions in the body, including supporting digestion, managing vitamin breakdown and formation, keeping bad bacteria at bay, and modulating overall gut health. In the face of widespread declining gut health today, supplementing with a probiotic is often recommended.

But how long does it take for a probiotic to work? 

In this guide, we’re answering that key question. We’ll also touch on factors that influence probiotic speed, explore how probiotics work within your body, discuss telltale signs of probiotic effectiveness, and more.

Jump straight to:

Factors Influencing Probiotic Efficiency

While most people will notice effects within 2 to 3 weeks, the truth is that the probiotic effectiveness timeline is unique for everyone. However, there are a few factors that can influence how quickly you’ll see results:

  • Personal health and gut flora balance – Most of the clinical evidence we have about probiotics is based on people in good health: those eating nutritious and varied diets, not actively taking antibiotics, and not experiencing any negative bowel or digestive symptoms. There’s a possibility that if you’re recovering from an illness or focusing on healthy eating for the first time, your probiotic timeline could look different from the average person's.

  • Type and strain of probiotic – The genus, species, and strain of the bacteria in your probiotic could influence its mechanism of action—and, thus, its timeline. Right now, most probiotics are made from seven main genera (“genera” is the plural of “genus”): Lactobacillus, Bifidobacterium, Saccharomyces, Streptococcus, Enterococcus, Escherichia, and Bacillus. Each of these genera includes different species, and multiple strains of one species can be made. Scientists are still exploring how each specific strain impacts the body.

  • Dosage and frequency of intake – If you’re consistently using your probiotic product per the package instructions, you might be more likely to see results quickly. However, if you occasionally skip a day, use a lower dose than recommended, or take a probiotic only occasionally, your probiotic might not take effect quickly.

  • Lifestyle and dietary habits – If you have a hard time maintaining a consistent eating schedule, don’t eat a wide variety of nutrients, or face chronic illnesses that impact your digestion (like Irritable Bowel Syndrome), these factors could change your experience while taking a probiotic.
  • Read more: The Best Probiotics for IBS Diarrhea [Strains & Brands] 

    What Happens to Your Body When You Start Taking Probiotics?

    There are three different mechanisms of action that apply to probiotics:

  • Non-specific mechanisms – These actions occur throughout various genera of bacteria, so you might experience these effects no matter which probiotic product you use. 
  • Species-specific mechanisms – These actions depend on the species (a subtype of a genus) of bacteria you introduce. So, you might only see these results if you use a specific species of bacteria. 
  • Strain-specific mechanisms – Strain-specific mechanisms are rare, as far as scientists have observed. Most probiotic effects depend on species, but some strains do offer novel effects (like immune system modulation).
  • Let’s start with non-specific mechanisms—the things happening in your body no matter which probiotic products you use:

  • Preventing pathogenic microorganism growth – By colonizing a specific area of your intestinal tract, a probiotic could help prevent the growth of bad bacteria.
  • Producing bioactive compounds – Probiotics often influence body processes, resulting in increased production of endogenous compounds (i.e., substances made inside the body) like fatty acids.
  • Moderating pH in the colon – Many bacteria have the power to change the overall pH of parts of the intestinal tract. However, it’s not entirely clear how this positively affects gut function yet.
  • Some species-specific mechanisms include toxin neutralization, vitamin production, bile breakdown, and enzyme activity. 

    To put it simply, probiotic bacteria find a home in your digestive tract, reproduce, and influence various gut functions as their colony grows. 

    How Do You Know If the Probiotic Is Working?

    While you can’t see any of the actions above, there are a few ways to tell if they’re happening inside your body. Let’s touch on a few telltale signs that your probiotic bacteria have started to take effect.

    Regular Digestion and Bowel Movements

    Improved overall digestion tends to be a top sign that a probiotic is truly working in your favor. When you have an infection, show other signs of constipation, or have diarrhea, a probiotic can step in to restore a natural balance of bacteria. Probiotics have been found to increase daily bowel movements as well as soften stool, making it easier to pass through the body.

    But probiotics don’t just make you poop more often—they can also:

    • Increase bowel motility (i.e., speed up the movement of waste through your GI tract)
    • Increase the number and overall weight of stools
    • Promote consistency (i.e., make your bowels more regular or predictable)

    If you’ve noticed any of the above effects, your probiotic is likely working as intended. 

    Minimized Bloating and Gas

    A major plus of using the right probiotic is reducing bloating and gas. Using a targeted, high-quality probiotic supplement can help restore the microbiome’s balance of good and bad bacteria. Doing this can help repair the gut and increase levels of healthy microflora. 

    In a recent study of people living with Irritable Bowel Syndrome, a probiotic product helped study participants mitigate symptoms like:

    • Abdominal pain
    • Gassiness
    • Bloating and cramping

    Whether you’re trying to overcome a specific GI challenge or you want to reduce occasional discomfort, limited bloating and gassiness is a sign that your probiotic is working.

    Read more: Best Probiotics For IBS Constipation 

    Increased Immunity

    Say goodbye to those pesky colds!

    Probiotics have been shown to help increase the body’s immunity by aiding in proper digestion and increasing nutrient absorption. In fact, more than half the cells that create antibodies for fighting sickness are in the intestines and in the gut. 

    Repairing the gut lining can take much-needed stress off the gut, which gives the body more energy to focus on fighting off sickness.

    Better Mood

    There has been a strong link found between the brain and gut connection:

    • Many of the same neurotransmitters in the brain are produced in the gut. 
    • The gut is responsible for producing nearly 90% of the serotonin in the body as well as dopamine and gamma-aminobutyric acid which also play a big role in regulating moods and feeling good. 

    Beyond supplements and products, knowing what types of food and lifestyle choices are harmful to gut health is important. Frequently consuming alcohol, sugar, and highly processed foods can increase inflammation in the body and lead to weight gain, skin irritations, and increased exhaustion. So, next time you’re at the store, consider picking up some probiotic-rich fermented foods and beverages to enrich your diet and health. 

    Read more: 7 Anti-Inflammatory Foods to Incorporate into Your Diet Now 

    Signs Your Probiotic Is Not Working

    On the other hand, your probiotic might not be working if:

  • You’re not seeing symptom changes – If you were dealing with bloating, constipation, or infrequent bowel movements before you started using a probiotic and you haven’t noticed any changes yet, your probiotic may not be working. 
  • Your bowel movements haven’t changed – If you haven’t seen any change in the frequency, size, or regularity of your bowel movements, the probiotic bacteria may not have colonized in your GI tract yet.
  • However, remember that: 

  • Probiotics take time to work – Bacteria take time to colonize and start to work their scientific wonders on your digestive system. Wait a few weeks before switching up your formula or routine.
  • Consistency is key – If you’re not seeing results, make an effort to be as consistent as possible. Take the same dose of the same product at the same time every day (or as often as the package instructions indicate) to increase your chances of success.
  • Consult a provider if needed – If your GI symptoms are excruciating or you haven’t seen any significant changes after multiple months of probiotic use, make an appointment with a healthcare provider. They’re the most qualified to diagnose any health issues and help you find a personalized, effective solution. 
  • How Long Does It Take for a Probiotic to Work

    As we mentioned, the effects timeline can look different for every probiotics user. However, you should notice some effects relatively quickly if you’re using probiotics per the product instructions:

    • Within the first few days of using a probiotic, you may actually experience some discomfort. This could include cramping, bloating, or changes to your bowels as your body adjusts to the influx of good bacteria. 
    • In the first few weeks of your probiotics course, you may start to notice small changes to your digestive activity: slightly more frequent bowel movements, slightly larger stools, or slightly decreased bloating. 
    • After a few months of probiotic use, your body will start to settle into a new normal. Your bowel movements may become very regular (around the same time each day, even), you may find that you’re less susceptible to minor illnesses like the common cold, or you may be in better spirits. These are all possible with the help of the right probiotic formula. 

    How to Choose the Right Probiotic for You

    What should you look for in a probiotic? Here are a few tips from experts:

    • Look for formulas containing strains of both Lactobacilli and Bifidobacteria. The yeast Saccharomyces boulardii could also provide positive results. However, scientists have yet to explore how every single probiotic bacteria impacts the body—don’t be afraid to try new formulas as needed.
    • Probiotics should contain live cultures—living organisms that can colonize in your GI tract. In addition, there should be a non-negligible quantity of organisms in your formula. Look for numbers in the billions of CFUs (colony-forming units).
    • Package labels should have specific instructions about when to use the product, how often to take it, and how much of the product you should use. 

    Optimal Probiotic Intake for Max Effect

    Optimizing your gut health isn’t just about using one product: it requires a somewhat holistic approach. To maximize the effectiveness of your product, remember to:

  • Combine probiotics with a healthy diet and lifestyle – One of the best ways to promote a healthy gut is to eat a wide variety of nutritious foods. A healthy diet and an exercise plan that works for you are just two of the building blocks of overall wellness. 
  • Select the right probiotic strain – Different strains of probiotic bacteria can have different effects on users. If you’re not sure where to start, choose a formula with one or two strains, use it consistently, observe your results, and try another formula if needed. Repeat this process until you find your perfect match.
  • Consider prebioticsPrebiotics are food for probiotics—the bacteria colonizing your gut have to eat something, after all. You can help probiotics perform their best by adding a prebiotic and probiotic combination supplement to your regimen or eating prebiotic foods like whole grains, bananas, and soybeans. 
  • Shop Digestive Vibrance, a prebiotic and probiotic combination

    Get the Best Probiotic for You

    So, how long does probiotic take to work for your gut health? 

    Ultimately, it’s hard to say. However, when your probiotics do start working, you’ll likely notice telltale signs that your microbiome is thriving, like frequent and consistent bowel movements. 

    Choosing the right probiotic product is one way you might ensure timeline results. To that end, consider Vibrant Health’s array of digestion health products—formulas packed with live cultures that can help your GI biome flourish with healthy bacteria. You can always trust our products: we value truth and transparency, so you always know what you’re getting in every probiotic dose, and exactly how much of it. 

    Take the next step for your gut health with a high-quality probiotic from Vibrant Health.



    The power of three, the convenience of one. Simplify your routine with a plant-based multivitamin, omega-3, and probiotic all in one capsule.

    The power of three, the convenience of one. Simplify your routine with a plant-based multivitamin, omega-3, and probiotic all in one capsule.