Key takeaways:
Probiotics are live microorganisms found in foods and supplements that support your gut health. They may provide the rest of your body with health benefits.
Taking too many probiotics may cause digestive symptoms like gas, bloating, and nausea. But a large dose of probiotics is unlikely to cause dangerous side effects in healthy people.
It’s a good idea to work with a healthcare professional to make sure you’re taking the right probiotic for you. Stick to the dose recommended on the packaging unless you’re instructed otherwise.
Probiotics are a popular topic in the health world because of the potential benefits for your gut and overall health. Many people are eating more probiotic foods or taking more probiotic supplements. But is it possible to have too much of a good thing?
Taking too many probiotics probably won’t cause dangerous side effects in most people. But it may cause some unwanted digestive symptoms. Below, we’ll get into what probiotics are and how to choose the right one for you at the right dose.
What are probiotics?
Probiotics are found in a variety of foods and supplements. They deliver live microorganisms to your intestines. Most probiotics are types of bacteria, although some are yeasts. Probiotics are often called “good bacteria.” This is because they may have several health benefits:
Reducing antibiotic side effects, including diarrhea
Helping with digestive disorders like irritable bowel syndrome (IBS)
Regulating blood sugar and insulin
Improving certain skin conditions like eczema
Strengthening your immune system
Lowering cholesterol levels
Preventing “bad” bacteria from multiplying in your gut, which can cause an imbalance that leads to inflammation in the intestine and throughout your body
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How many probiotics should you take?
There’s no one-size-fits-all dose for probiotics. The amount you should take depends on several factors:
The concentration of the supplement (the amount of probiotics in it)
Your current symptoms and reason for taking the probiotic
Your health goals
The form of the probiotic (pill, powder, or liquid)
Follow the recommended dose on the supplement label — unless otherwise instructed by a healthcare professional.
Some supplements suggest taking 1 to 2 capsules per day based on your symptoms. Others suggest taking 2 to 4 capsules per day, or as recommended by a healthcare professional. A probiotic in powder form will have different dosing guidelines, such as “1 scoop or 1 packet per day, mixed in food or water.”
How many probiotics are in supplements and foods?
Most probiotic supplements provide about 1 to 10 billion colony-forming units (CFU) — the number of living cells — per dose. Some offer 50 billion CFU or more.
Certain probiotic foods, like yogurt with live and active cultures, may contain even more CFU than that. But this depends on how much you consume and how regularly you consume it.
You don’t need to eat fewer probiotic foods if you start taking a probiotic supplement, or vice versa. Monitor any symptoms and talk with a healthcare professional if you have concerns.
Common side effects of probiotics
Probiotics are safe for most people to take. Most of the common probiotic types are unlikely to cause side effects in healthy people. If side effects do occur, they’re usually mild digestive symptoms, like gas or bloating. These side effects often improve as your body gets used to the new bacteria in your gut.
If you do experience digestive side effects, you don’t need to stop taking the probiotics if your symptoms are mild and tolerable. But it may help to cut back until your body adjusts.
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Note that some groups of people may be at a greater risk of more serious side effects from probiotics, such as:
Premature infants
People with a critical or serious illness
People with a weakened immune system, such as those with an autoimmune disease or who are receiving cancer treatments
People with short bowel syndrome
It's a good idea to talk with a healthcare professional about any supplements you’re considering taking — whether or not you’re at risk of more serious side effects from probiotics.
What happens if you take too many probiotics?
A large dose of probiotics is unlikely to be dangerous for most people. But more research is needed to learn whether it’s possible to have too many probiotic bacteria in your gut or if there are any long-term consequences. Keep in mind that while probiotics have health benefits, taking more of them isn’t necessarily better.
It may take your body some time to adjust when you first start taking probiotic supplements. This is also true if you eat a lot more probiotic foods than usual. You may have an upset stomach, bloating, or gas. But these symptoms should improve as your body adapts.
How to choose the right probiotic foods and supplements for you
There are hundreds of different probiotic types, also called strains. Seven “core” probiotic strains are most often used in probiotic products:
Lactobacillus
Bifidobacterium
Saccharomyces
Streptococcus
Enterococcus
Escherichia
Bacillus
Different probiotic strains can benefit different functions in your body. You may benefit from taking the probiotic strain that targets your unique health goals or conditions (more on this below).
The World Gastroenterology Organization (WGO) has a list of specific probiotic types that have been found to help with different health conditions.
Probiotic foods
Probiotics are a natural byproduct of the fermentation process. This makes fermented foods one of the main natural sources of probiotics. Examples of probiotic foods include:
Some types of yogurt (look for the wording “contains live and active cultures” on the packaging)
Kombucha, kefir, and other probiotic drinks
Cultured buttermilk
Miso
Tempeh
Sauerkraut
Kimchi
Some cheeses
Sometimes, probiotics are added to packaged foods. But the amount of probiotics in these foods is usually less than you’d get by eating foods that naturally contain probiotics.
Probiotic supplements
Probiotic supplements are one of the most commonly used supplements among adults in the U.S. You can get a good dose of probiotics from both foods and supplements. But if you want to address specific health concerns, you may want to consider taking probiotic supplements instead of relying solely on probiotic foods. There are a few reasons for this:
Supplements contain specific types of probiotics. Taking supplements with specific strains is a good way to target specific health conditions. For example, Lactobacillus acidophilus has been shown to help with lactose intolerance. Bifidobacterium bifidum may help symptoms of IBS. With foods, you don’t always know which exact probiotic strain you’re getting, or how much.
One supplement can contain multiple types of probiotics. Research shows that taking different types of probiotics together might be better for you than consuming just one type. For this reason, many probiotic supplements contain multiple types of probiotics. Some foods contain multiple probiotic strains too. But they aren’t necessarily in amounts that can target specific health concerns.
Probiotic supplements are sometimes more accessible. Consuming probiotic foods may not always be practical. For example, some probiotic foods may go against your cultural practices or dietary restrictions. Also, probiotic foods aren’t always available. In these cases, supplements may be a good choice.
How do you choose the right probiotic supplement?
Dietary supplements don’t have to follow the same FDA regulations as medications. This means that the label may not accurately reflect what is (or isn’t) in the supplement. Before taking any probiotic supplement, make sure you do the following:
Talk to a healthcare professional. They can help you find the right supplement and dose for your specific health goals.
Decide which probiotic form you want to take. There are plenty of options, such as capsules, powders, or chewable tablets. Consider which form is best for your lifestyle and preferences. Also, think about which form you’re most likely to take consistently.
Buy from professional, trusted brands. Choose supplements that have been third-party tested by NSF, United States Pharmacopeia (USP), or ConsumerLab. Products with certifications from these organizations have been voluntarily monitored and tested to make sure they contain what the labels say they contain.
Read the label. Choose a supplement that has no added sugars, allergens, or preservatives.
Frequently asked questions
There’s early evidence that certain strains of probiotics can be helpful in reducing the risk of cardiovascular disease. Lactobacillus and Bifidobacteria have been linked to:
Lower blood pressure control
Improved cholesterol
Less inflammation
But some cardiologists and other healthcare professionals warn that research is limited and ongoing, and there are risks with probiotic use. It’s best to talk to a healthcare professional before starting any probiotic or supplement to make sure it’s safe for you.
There are some probiotics that are marketed as natural boosters for glucagon-like peptide-1 (GLP-1) medications. But there’s no solid evidence that these products work to enhance weight loss. Although they’re considered natural alternatives, talk to a healthcare professional before adding a supplement to your GLP-1 treatment plan.
There’s no single best probiotic. Different strains are linked to different health benefits. And the one that may work best for you depends on your health goals. If you’re thinking about adding probiotics to your health regimen, get some advice from a healthcare professional. They can give you guidance on a good place to start.
There’s early evidence that certain strains of probiotics can be helpful in reducing the risk of cardiovascular disease. Lactobacillus and Bifidobacteria have been linked to:
Lower blood pressure control
Improved cholesterol
Less inflammation
But some cardiologists and other healthcare professionals warn that research is limited and ongoing, and there are risks with probiotic use. It’s best to talk to a healthcare professional before starting any probiotic or supplement to make sure it’s safe for you.
There are some probiotics that are marketed as natural boosters for glucagon-like peptide-1 (GLP-1) medications. But there’s no solid evidence that these products work to enhance weight loss. Although they’re considered natural alternatives, talk to a healthcare professional before adding a supplement to your GLP-1 treatment plan.
There’s no single best probiotic. Different strains are linked to different health benefits. And the one that may work best for you depends on your health goals. If you’re thinking about adding probiotics to your health regimen, get some advice from a healthcare professional. They can give you guidance on a good place to start.
The bottom line
Probiotics are one of the most common supplements in the U.S. Serious side effects from taking too many probiotics are unlikely. But you may experience minor side effects like gas or bloating if you’re taking them for the first time or if you suddenly increase your dose. You should always speak with a healthcare professional about which type and how many probiotics to take. It’s also a good idea to stick to the dose recommended on the supplement packaging, unless a healthcare professional tells you otherwise.
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References
Blaabjerg, S., et al. (2017). Probiotics for the prevention of antibiotic-associated diarrhea in outpatients—A systematic review and meta-analysis. Antibiotics.
Bodke, H., et al. (2022). Role of probiotics in human health. Cureus.
Certifications. (2023). How to tell if your supplements are third-party certified and why you should care. Nutrasource.
Doron, S., et al. (2015). Risk and safety of probiotics. Clinical Infectious Diseases.
Gao, T., et al. (2023). The role of probiotics in skin health and related gut–skin axis: A review. Nutrients.
Guarner, F., et al. (2017). Probiotics and prebiotics. World Gastroenterology Organization.
Guglielmetti, S., et al. (2011). Randomized clinical trial: Bifidobacterium bifidum MIMBb75 significantly alleviates irritable bowel syndrome and improves quality of life--a double-blind, placebo-controlled study. Alimentary Pharmacology & Therapeutics.
Hashish, R., et al. (2025). The promising role of probiotics in the prevention of cardiovascular risk factors and their implication in reducing coronary artery disease: A literature review. Cureus.
International Food Additives Council. (n.d.). Probiotics.
Kechagia, M., et al. (2013). Health benefits of probiotics: A review. ISRN Nutrition.
Kwoji, I. D., et al. (2021). Multi-strain probiotics: Synergy among isolates enhances biological activities. Biology.
Office of Dietary Supplements. (2025). Probiotics. National Institutes of Health
National Science Foundation. (n.d.). Supplement and vitamin certification.
Nyanzi, R., et al. (2021). Invited review: Probiotic yogurt quality criteria, regulatory framework, clinical evidence, and analytical aspects. Journal of Dairy Science.
Pakdaman, M. N., et al. (2016). The effects of the DDS-1 strain of lactobacillus on symptomatic relief for lactose intolerance - a randomized, double-blind, placebo-controlled, crossover clinical trial. Nutrition Journal.
Ruan, Y., et al. (2015). Effect of probiotics on glycemic control: A systematic review and meta-analysis of randomized, controlled trials. PLOS One.
Syngai, G. G., et al. (2016). Probiotics - the versatile functional food ingredients. Journal of Food Science and Technology.
U.S. Food and Drug Administration. (2024). Questions and answers on dietary supplements.
U.S. Pharmacopeia. (2026). Choosing a quality supplement.
WIC Works Resource System. (n.d.). Probiotics. U.S. Department of Agriculture.
Wilkins, T., et al. (2017). Probiotics for gastrointestinal conditions: A summary of the evidence. American Family Physician.
Yan, F., et al. (2011). Probiotics and immune health. Current Opinion in Gastroenterology.
