Can Probiotics Cause Diarrhea?

Probiotic supplements are gaining popularity as a treatment for problems like inflammatory bowel disease, immune system benefits, and even acne. There are many health benefits to adding a probiotic supplement to your diet, but probiotics can also cause side effects like headache and diarrhea.

What is a Probiotic?

A probiotic is a type of beneficial bacteria that helps to keep the gut microbiota in a healthy balance. While every living thing has different bacterial strains inside their body, too many bad bacteria can cause digestive problems, acid reflux, and even a weakened immune system.

Probiotics help your body keep a balance of more healthy bacteria than problematic bacteria.

Probiotics are naturally found in certain foods, including yogurt, kombucha, soft cheese, and many fermented foods. However, many people find it easier to take a probiotic supplement than to look for probiotics in foods.

What is the Role of Probiotics in the Human Body?

Every person has both good bacteria and bad bacteria living inside their body. Many people suffer from poor gut health caused by too many bad bacteria and not enough good bacteria as part of their gut microbiome.

Probiotic bacteria in the gut help the human body break down food and turn it into usable energy. These good bacteria help the digestive system work more efficiently and may even help mild stomach upset caused by lactose intolerance.

Besides improving digestive health, good bacteria can fight off harmful bacterial strains that may cause poor immune function, unhealthy skin, and central nervous system problems.

What Are the Types of Probiotics?

There are many different strains of probiotics. Some of the most common include:

  • Bifidobacterium Longum
  • Bifidobacterium Animalus
  • Bifidobacterium Lactus
  • Bifidobacterium Longum
  • Bifidobacterium Breve
  • Lactobacillus Acidophilus
  • Lactobacillus Reuteri

While they each differ slightly, all of these strains can improve your overall health by bringing a healthy balance to your gut flora.

What Are the Benefits of Taking Probiotic Supplements?

As probiotic supplements become more popular, researchers have spent more and more time exploring the health benefits of probiotic use.

Promotes Healthy Bacteria in the Body

Consuming probiotics ensures that there are more good bacteria than bad bacteria in the body. There is evidence showing that the standard American diet actually promotes poor gut health and an imbalance of good and bad bacteria. In addition to eating a more healthy diet, taking a probiotic supplement can help counteract the effects of a poor diet and bring balance back to the gut microbiome.

Reduces the Severity of Irritable Bowel Syndrome

Irritable bowel syndrome (IBS) is a chronic and often debilitating health condition caused by an improper immune system response, overgrowth of bad bacteria, and stress. Probiotics work to improve symptoms of IBS by limiting the growth of unhealthy bacteria and improving immune function in the gut.

Prevents Diarrhea

Probiotic supplements can prevent diarrhea caused by viral and bacterial illnesses, Crohn’s disease, IBS, and antibiotic-associated diarrhea.

Unfortunately, when a healthcare provider prescribes antibiotic treatment for an infection, the antibiotic attacks both the harmful and beneficial bacteria. A solution to this struggle is taking a probiotic every time you are prescribed an antibiotic can help combat antibiotic-associated diarrhea.

How Do I Take a Probiotic Supplement?

If you want to start taking probiotics, there are a few things you should keep in mind.

  • Take your probiotic supplements on an empty stomach about 30 minutes before a meal.
  • Store your probiotic supplements properly since some probiotics may require refrigeration.
  • Always read the ingredient label on your probiotic supplements, paying special attention if you have food intolerances or allergies.
  • Be consistent, and continue taking your probiotic for about a month while your body adjusts.
  • Throw out any expired prebiotics. Since probiotics are live bacteria, they often have a shorter shelf life than other types of supplements.
  • Follow the instructions on the label, and do not exceed the maximum dosage of probiotics.

Do Probiotics Cause Diarrhea?

For some people, probiotics may cause diarrhea, gas, and bloating. Choosing a high-quality probiotic product reduces the risk of diarrhea but does not eliminate it. Taking your probiotics on an empty stomach, taking small doses to start, and letting your body adjust to probiotic supplementation can improve the regularity of your bowel movements.

What Types of Foods Contain Natural Probiotics?

There are many foods that contain naturally-occurring probiotic strains. These include yogurt, kefir, cereal, juice, sauerkraut, kimchi, miso, tempeh, soy, soft cheese, and buttermilk.

While these foods contain probiotic strains, the probiotics can be destroyed by cooking, filtering, or pasteurization. Probiotics are live bacteria, and any process that destroys harmful bacteria will also eliminate the probiotics. Make sure to use safe food handling practices when dealing with probiotic-rich foods, such as storing them at safe temperatures and washing your hands thoroughly.

It is also important to remember that not all fermented foods contain probiotics. Fermented foods like sourdough bread, beer, and wine, do not contain any live probiotics.

Do Probiotic Foods Cause Diarrhea?

Similarly to probiotic supplements, probiotic-rich foods can cause diarrhea, gas, and bloating. This is especially true if you change your diet abruptly. Even though probiotics are good bacteria, your digestive tract needs time to adjust to the change in gut microbiota.

When you consume foods high in probiotics, be kind to your gastrointestinal tract and add new foods slowly. Making a huge change in your diet can cause uncomfortable side effects, even when the change is for the better.

What Are the Side Effects of Probiotics?

While many people experience health benefits from using probiotics, there are a few side effects that you should be aware of. The most common side effects of probiotics are short-term and will fade as the digestive system adjusts to a healthy balance of bacteria.

  1. May Cause Digestive Symptoms

Because probiotics can cause a big shift in the gut flora, the digestive system may have a strong reaction to adding a probiotic supplement. Taking probiotics for the first time can lead to gas, bloating, stomach pain, and diarrhea. This typically resolves over a few weeks as the body adjusts to the effects of the new supplement.

Most experts recommend giving the body at least a month to adjust to probiotic supplementation. If you are still experiencing uncomfortable digestive systems after four weeks, you may need to switch to a different strain or talk to your healthcare provider about your symptoms.

  1. Headaches

Some probiotic-rich foods contain biogenic amines, which can cause headaches in people who are sensitive. Biogenic amines are more likely to cause problems for people who are already prone to migraine headaches. Headaches caused by an increase in probiotic foods usually subside with time.

Probiotic supplements do not usually contain enough of these amines to cause migraines. However, poor-quality supplements may contain additives that can lead to head pain.

  1. Increased Histamine Levels

Some strains of probiotics, including Lactobacillus buchneri, Lactobacillus helveticus, Lactobacillus hilgardii, and Streptococcus thermophilus, are known to increase histamine levels in the gut.

For most people, increased histamine levels in the gut do not cause any problems. Usually, the body uses an enzyme called diamine oxidase to break down histamine in the gut and eliminate any potential histamine reactions. However, people with a diamine oxidase deficiency may experience hives, itching, and low blood pressure when histamine levels in their gut rise.

Adverse Reactions

It is extremely important to read the label of any probiotic supplement you choose to take. Many probiotic supplements include common allergens such as soy, gluten, lactose, and eggs. In addition, probiotics are not regulated by the FDA, meaning that manufacturers have a lot of freedom in the ingredients that can be used in their supplements.

Make sure you only purchase probiotics from a company you trust and check the ingredient label every time you get a new bottle. Manufacturers may make small adjustments to their formulas, even if the bottle looks the same.

Increased Infection Risk

While probiotics have been shown to improve immune function, they may be problematic for people with severely compromised immune systems. Studies have shown that children with severe immune deficiencies and people receiving chemotherapy treatment are at an increased risk of fungal and bacterial infections with probiotic supplement use.

In addition, people with small intestine bacterial overgrowth (SIBO) may notice that their symptoms get worse with probiotic supplementation. Small intestine bacterial overgrowth can cause symptoms similar to IBS and is common in older aged females.


Overall, daily probiotic use is a good way to take care of your digestive tract by balancing your gut microbiome. In addition, adding probiotics can improve your immune function, clear up your skin, reduce depressive symptoms, and help you manage IBS.

As with any supplement or medication, make sure you discuss your plans to add a probiotic supplement with a healthcare professional. If you have severe allergies, compromised immune systems, a history of migraine headaches, or a diamine oxidase deficiency, be extra careful when starting a new probiotic supplement.