How Long Does it Take for Probiotics to Work?

How Long Does it Take for Probiotics to Work?

  • Probiotics 101

  • By Jef L’Ecuyer, Registered Dietitian

    How Long Does it Take for Probiotics to Work?

    Adding a new healthy habit to your daily routine is an exciting endeavor. During the first few days, you may be eager to see quick results. But like with any new healthy habit, it can take time and consistency to notice the impacts of adding a probiotic supplementation to your daily routine.

    Don’t worry, this doesn’t mean they’re not working! 

    Instead of growing frustrated or discouraged, it’s important to exercise patience and trust that your probiotics are working under the radar to support your gut microbiota.

    So, how long does it take for probiotics to work? It can take a couple of weeks, depending on several personal factors. Below, we’ll explain how probiotics work and discuss the average timeline involved in improving various gut-related conditions.

    How Do Probiotics Work?

    Put simply, deliver more “good” bacteria to your gut. Maintaining an optimal balance of beneficial bacteria and bad bacteria within your gut microbiota is essential to nurturing your overall health. 

    When your gut is overrun by harmful bacteria, a condition known as dysbiosis, you may experience: 

    • Digestive difficulties
    • Weaker immune function
    • Poor nutrient absorption
    • Mental health problems 

    This bad bacteria takeover may arise in response to stress, a poor diet, illness, or recent antibiotic use. 

    Fortunately, the beneficial bacteria found in probiotics can help restore your gut’s balance and may reduce its inflammation to prevent digestive issues. This good bacteria may also push out some of the “bad” bacteria behind your health woes, leaving you with an altogether healthier digestive system.

    With consistent use, probiotics have the potential to improve your:

    • Digestion
    • Nutrient absorption
    • Immune function
    • Mental health
    • Mood and energy levels
    • Weight loss efforts
    • Skin conditions
    • Heart health

    While probiotics are important for maintaining gut health, they aren’t a magic pill that immediately works overnight. Unlike many medications out there, probiotics don’t just relieve the symptoms of your gut-related health conditions. Instead, they address the root cause (if the cause of your condition is gut-related). In turn, you can’t expect a quick fix. 

    Upgrading your gut health from the ground up takes time.

    Let’s take a look at how much time you can expect to wait before reaping the health benefit of taking probiotic supplements

    Start every day off right with a probiotic beverage on the go. Find in store!

    How Long Do Probiotics Take to Work?

    As a general rule, it can take around one to four weeks of consistent probiotic intake to see their positive impact. The specific amount of time depends on the condition you’re trying to improve, your unique body composition, and the quality of your probiotics. 

    Looking for the fastest possible route to recover? Let’s take a deeper look at each of these three primary factors.

    #1 Your Symptoms

    The time it takes for probiotics to “work” depends on what you define as “working.” Different gut-related conditions respond to probiotics at different rates.

    Here’s a basic overview of the average time it takes for probiotics to help improve the following conditions:

    Acute diarrhea 

    After a round of antibiotics, some people may develop acute diarrhea. Probiotics can help clear up cases of antibiotic-induced diarrhea relatively quickly. On average, it takes around one to five days. For example, we suggest taking Bio-K+ probiotics while on antibiotics and for five days after the end of treatment to help prevent antibiotic associated diarrhea.

    Probiotics can help mitigate constipation in as little as two weeks. However, more significant improvements tend to occur around week four. It’s also important to start with a lower dosage of probiotics, to give time to your microbiota to get used to the new bacteria.

    Irritable bowel syndrome

    Some studies have shown that probiotics can help improve IBS symptoms, including bloating, flatulence, digestive discomfort and quality of life, within one to twelve weeks.

    • Even if taking probiotics help clear up your IBS symptoms within this timeframe, it’s important to keep taking them. 

    Note: Initially, starting a probiotic supplement may cause some bloating. This can occur as the healthy bacteria integrate into your gut microbiota. Over time, this side effect should subside. 

    Dairy intolerance 

    Are you tired of missing out on ice cream and grilled cheese sandwiches? Luckily for you, some promising research shows that probiotics may be able to reduce dairy intolerance over the course of two months to three years of consistent supplementation.

    Immune health 

    Coming down with a cold or flu is a nuisance. A strong immune system can help you stay healthy and fight off illnesses faster. 

    Like so many things, strong immune function begins in the gut. That’s because 70% to 80% of your immune cells live within your intestines. By fortifying your gut health with probiotics, your immune system operates at peak capacity. In turn, your body may have an easier time fighting off infections. 

    Just how quickly could you start feeling fit and strong? One small study showed that probiotics reduced the rate of respiratory infections in people who took them regularly for 12 weeks. 

    Weight management

    Your weight loss efforts may benefit from probiotics, but it takes time to yield results. One study found that it took around 12 weeks of probiotic supplementation for overweight individuals to experience noticeable fat loss. It’s always recommended to consult a registered dietitiation when you want to make  changes in your diet. 

    These are just a few of the conditions that may benefit from taking probiotic supplement. While probiotics’ health benefits are vast, it’s important to note that they may not be the right solution for your health conditions. Your primary doctor will be best equipped to determine whether probiotics are the right choice for you and your health goals.

    #2 Your Body

    Everybody is different—more specifically, every body is different—and so is their baseline gut health.

    If your gut is highly inflamed or suffering from dysbiosis, your road to recovery may take longer than someone whose gut flora is only slightly out of balance.

    In addition to your current gut health, the following factors could impact how quickly your body responds to probiotics:

    • Age
    • Genetics
    • Stress levels
    • Diet
    • Frequency of antibiotic use

    #3 Your Probiotic Quality

    Lastly, the quality of your probiotics plays a role in their efficacy and efficiency when it comes to supporting a healthy gut. 

    Pay close attention to the following factors, whether you’re browsing the pharmacy aisle or scrolling online:

    • Colony-forming units (CFUs) – Probiotics are measured in CFUs, which let you know how many live bacterial cells are in a single probiotic capsule.

      Probiotic bacteria strain with higher CFUs may be more effective and fast-acting than those with lower CFUs. For example, in one study, probiotics with over 10 billion CFUs were found to be the most effective at treating gastrointestinal issues.

    • Strain – There are hundreds of different strains of good gut bacteria that help support a healthy gut. Some strains may help you improve certain health conditions better than others. 

      If you’re trying to improve a specific condition, it’s important to take a probiotic strain that’s properly suited for the job. 
    • Usage instructions – We’ve already discussed just how complex the gut microbiota is—as such, the way you take your probiotics can impact their effectiveness on your digestive issues and overall health. Generally, it’s best to ingest probiotics on an empty stomach. However, you should always follow the specific use instructions on your bottle of probiotics.

    • Storage – Probiotics are alive and therefore fragile. They may be sensitive to heat, light, and humidity. As a result, there’s an “improper” way to store certain probiotics, which can reduce their effectiveness. Some brands of probiotics should be refrigerated. 
    • Quality – Lastly, the quality of your probiotic supplement can make or break how well—and how fast—they work. Due to a lack of FDA regulation, probiotic quality can vary greatly from brand to brand. Just take a look at these statistics from one study:

      • Only half of the examined probiotics contained the specific strains listed on their labels.

      • Forty-three percent of probiotics contained less than half of the healthy bacteria listed on their labels. 

    For the most noticeable benefits and the highest quality of life, it’s important to purchase a brand you can trust. At Bio-K+, we pride ourselves on producing the highest quality probiotics. Our capsules and drinkables have gone through extensive clinical testing, so you can trust their efficacy.

    The Bottom Line: Be Patient With Your Probiotics

    Between controllable factors like purchasing the right brand of probiotic product, when to take probiotics, and total unknowns like your body’s unique response to probiotic formulas, there’s no exact timeline on how quickly your digestive symptoms will subside—you can only approximate how quickly it’ll take for your probiotic product to work.

    And even then, your approximation may be way off. That doesn’t mean it’s not a routine worth sticking to.

    Remember, Rome wasn’t built in a day, and neither will your optimal gut microbiome. If you’ve been struggling with issues with your intestinal tract for years, improving them can take some time. Even if you don’t notice results right away, knowing how probiotics work can help you stick to the plan, knowing that they’re doing their job behind the scenes. 

    Bio-K+: Top-Notch Quality You Can Trust

    When you’re waiting for your probiotics to work, the last thing you want is to question their quality and efficacy. With our high-quality probiotic capsules and drinkables, you can rest assured that the healthy gut bacteria is doing its job. Our new Extra Line contains proven, patented probiotics that make a perfect addition to your healthy lifestyle. 

    To start your probiotic journey today, visit Bio-K+.


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    Jef L’Ecuyer Registered Dietitian
    About the author

    Après sa formation de nutritionniste à l’université McGill, Jef s’est lancée dans le domaine de la santé gastro-intestinale avec un intérêt particulier pour le microbiote et le syndrome de l’intestin irritable.

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