How Long Does It Take Probiotics to Work?

Posted by Dr. Ian Stern Admin on


By now most of us have at least heard of probiotics. You might have seen the term on your yogurt or smoothie or heard it from a health-crazed friend. Maybe you’ve even started taking them yourself! 

Probiotics have become a mega-industry in recent times, and for good reason. If taken properly, they can be extremely beneficial in resolving or improving a multitude of health issues as well as just in contributing to your overall sense of well being and happiness. So what are probiotics? 

Probiotics are described as “Live microorganisms which, when consumed in adequate amounts, confer a health benefit on the host” by the Food and Agricultural Organization of the United Nations and the World Health Organization [1]. Simply put, probiotics are “good” bacteria. 

The word “bacteria” sounds scary because we associate it with harmful germs and disease. But those are the bad bacteria, which probiotics actually can keep away. If you’re lucky, your body is already filled with over a hundred trillion good bacteria, consisting of various strains and species. And not only are they good for you, but they are basically essential to your survival. These bacteria help you get the nutrients from the foods you eat, fight off infections, and support the integrity of the wall of your intestine. 

The gut microbiome is the community of bacteria, fungi, and viruses that live inside a “pocket” of your large intestine called the cecum. The majority of research done on the microbiome is fairly new (most studies have been conducted only over the last twenty years or so), but already there are numerous findings on the benefits of having a healthy balance of bacteria in the gut., 

Sand scientists are continuing to uncover more connections between the deficiency thereof and various diseases, such as diabetes, obesity, and heart disease, as well as mental conditions, such as depression and anxiety. These are all conditions that good quality probiotics can help resolve! 

Why Probiotics Might Work Rapidly

There are many variables when it comes to how long it takes probiotics to work. Here we’ll cover reasons they might work very quickly. If you’re using a high quality, potent probiotic supplement with billions of microorganisms and a high colony forming unit (CFU), which is proven to survive the harsh acidic conditions of the stomach, it’s possible that you’ll feel the effects in as quickly as a few hours after ingestion. And some people do!  

Immediate Immune Modulation & Inflammation Suppression

Probiotics have shown to both enhance homeostatic immune defenses and ease infectious, inflammatory and allergic diseases by modulating gut function [2].  When you introduce billions of good bacteria into the gut, there could be an immediate positive response in your body’s immune system. 

Probiotics confer health benefits through multiple action mechanisms including modification of immune response in gut associated lymphoid tissue [3]. It is believed that 70% of all our immune cells are in the gut. Probiotic supplementation may immediately reduce or suppress concentrations of inflammatory cytokines, which may immediately affect neurotransmitter production in the brain. That could explain why someone would consciously notice the effect of probiotics shortly after ingestion.

Efficient Absorption of Probiotics & Instant Gut Modification

You should be taking a good quality probiotic, containing billions of bacteria, a high CFU (colony forming unit) and formatting (allowing the bacteria to survive in the acidic environment of your stomach). If so, your supplement should also have efficient pharmacokinetics, meaning that the bacteria will be transported quickly and efficiently exactly where they need to go, and gastrointestinal colonization will follow. At that point some begin to feel immediate physiological effects, which are hypothesized to be due to the suppression of inflammation. 

Antioxidant Effect 

Probiotics have been shown to facilitate an antioxidant response within the body. Antioxidants help to counteract oxidative stress by neutralizing excess free radicals to protect cells and prevent illness. This results in a feeling of well-being. 

Nutrient Absorption and Intestinal Barrier Restoration 

Those who have a damaged intestinal lining may find that the bacteria delivered by probiotics begin immediately restoring it, as a result of which you may be able to absorb more nutrients from foods.  If you had a preexisting nutrient deficiency, you may notice a rapid effect due to increased absorption of nutrients.

Probiotics Quickly Alter PNS & CNS Activation

Since the gut is closely connected to the brain, when good bacteria are added to the intestine, therefore changing the microbiota, activity in the peripheral and central nervous system is altered. The new bacteria that colonize in the gut interact with the enteric nervous system (ENS), which governs the function of the gastrointestinal tract. 

In fact, autoimmune diseases of both the central and the peripheral nervous system (PNS) have been linked to microbiota. A very recent study established the missing link between the central nervous system (CNS) and the immune system i.e., thus completing the microbiota-neuronal-immune system triangle [4].

The Placebo Effect

And of course, as with any supplements, there are some who experience great results sooner due to what is referred to as the Placebo effect. In other words, by expecting and believing that the probiotic will work, they experience beneficial effects. Our thoughts are powerful. 

Why Probiotics Might Work Slower

Every person is different. The effect of probiotics may differ according to the initial state of your microbiota. If you have severe dysbiosis (usually resulting from exposure to various environmental factors, including diet, toxins, drugs, and pathogens), it may take more time for you to experience the therapeutic effects of probiotics. In addition, due to physiologic adaptations within the peripheral and central nervous system, in some cases it may take up to four weeks to feel the benefits of probiotics.

You Have a Low Quality Probiotic 

If after about a month of regular supplementation (and proper dosage), you don’t experience any positive changes (or if you experience side effects, which can include headaches, bloating, diarrhea or constipation, or anxiety, which stop when you stop taking the probiotic), it may be a sign that you have a low quality probiotic. Unfortunately, many products on the market are mostly ineffective. 

They contain bacteria, which are either dead upon administration or will die when they come in contact with stomach acid. Many commercial brands don’t measure up. They are unstable in stomach acid. Quality matters triple when it comes to probiotics, and due to the very delicate process (and testing) required to create an effective probiotic supplement, generally the price of quality probiotics will be higher. 

Here is what you should pay attention to when choosing a quality probiotic: 

  • Clinical Testing - It's a great sign if the company is using strains that have been used specifically in clinical trials at a dose similar to or the same as that used in the study. This is one of the best ways to guarantee a probiotic's effectiveness. 
  • Potency (CFU count) - Choose a potent probiotic supplement that contains billions, not millions, of CFU (colony-forming units). The more imbalanced or sicker your gut, the higher will be the potency that you will require to feel results. If you have Crohn’s disease or a leaky gut, for example, you may need to take up to a total of 200 to 400 billion CFUs daily. Otherwise, 50 billion CFUs may be enough to start with. 
  • No fillers, additives, GMOs – Lower quality products may have fillers, such as corn starch, dairy, wheat, or soy. Depending on your sensitivity to these products, you may experience bloating or other side effects. 
  • Expiration Date and Refrigeration – Your product should have an expiration date and instructions on whether it needs to be refrigerated (some products do). These things are important to preserve the guaranteed potency of your product.
  • Multiple Strains – Lastly, look for a proprietary blend, containing diverse strains. It should at least contain both the Lactobacillus and Bifidobacterium strains, as well as others such as Strep. thermophilus and Saccharomyces boulardii, for example. 

Substance Use or Abuse

Many over-the-counter drugs, and especially antibiotics, have significant implications on the microbiota, since they destroy the beneficial bacteria. In addition, substance abuse such as cocaine addiction significantly alters the microbiome. Therefore, the rate at which even a quality probiotic supplement will take effect on your body will likely be slower when combined with other substances.  However, there are also studies that suggest that taking probiotics may actually help people with drug addictions [5]

Diet and Exercise

As is usually the case with most supplements, probiotics will be most effective with proper diet and exercise. A diet filled with processed foods as well as the presence of antibiotics in consumed meats and other products could negatively impact the rate at which the probiotics take effect in the body. In addition, some probiotic strains could vary in functional and technological properties in the presence of different food ingredients.  Exercise too has been shown to have beneficial impact on gut microbiota diversity [6]. Therefore, to maximize the effect of your probiotic, eat well and make sure to get plenty of exercise. 

Other Variables That Impact Probiotic Onset of Action

Other factors that could impact probiotic onset of action could include environmental factors (such as exposure to higher than average pollution, for example), body fat, genetics, intestinal permeability, medical conditions, “downstream effects” of other supplements, etc. 

The Long-Term Benefits of Probiotics 

In the long run, quality probiotics may produce a multitude of beneficial effects on your emotional, cognitive, and physical well being. The benefits of probiotics are still being uncovered, but already it can be said that probiotics may help with anxiety and mood disorders, digestive troubles, sugar cravings, and obesity. They may give you greater energy, more joy and happiness (the digestive tract is responsible for producing 90% of the serotonin in our bodies), and clearer skin. 

In addition, probiotics may very well be the solution for disorders that frustrate conventional medicine. More digestive disease specialists are recommending probiotic supplements for irritable bowel syndrome, for example. Clinical studies suggest that probiotic therapy can help treat several gastrointestinal illnesses, prevent and treat allergies in adults and children, as well as vaginal and urinary infections in women. There have been very promising results in the treatment or prevention of eczema, Crohn’s disease, the recurrence of bladder cancer, ulcerative colitis, and other medical conditions. Probiotics also contribute to nutrient absorption and help build the immune system. The long-term benefits of probiotics are tremendous.

What Are the Side-Effects From Too Many Probiotics?

Very little evidence suggests that a person can overdose on probiotics.  Regardless, always read the instructions carefully, and do not exceed the recommended dosage. The optimal dosage can vary, depending on a person's health and the type of probiotic product. Probiotics are generally safe and any side effects are often short-lived and mild. When first using probiotics, some people experience mild digestive issues, such as gas, bloating, or diarrhea due to changes in the gut microbiota, where the bacteria produces more gas than usual. However, these side effects usually clear up within a few days or weeks of taking the probiotics. If a probiotic causes any side effects or symptoms, consider reducing the dosage or refraining from taking the product.


It’s no wonder that probiotics literally means “for life” (pro, biota - life). Probiotic-rich foods and supplements may be a key player in improving your health and the quality of your life. That being said, you should always practice caution in choosing a good quality supplement. Make sure the ingredients, instructions, and expiration date are clearly marked on the label. Research each ingredient or ask your health practitioner. Steer away from any harmful fillers, allergens, and GMOs.   My Rebalance Probiotic Supplement has been specifically formulated to meet all of this criteria and I can stand behind its effectiveness 100%. 

Other Souces: